separate issues. Our own analysis in this book shows that a return to
full employment is possible. The main instrument is to get rid of the
tax void. Employment does not depend upon growth per se but employment
depends upon a properly working system to allocate the work that is
being done in an economy. Growth comes only into the story when we
aspire at higher welfare by means of higher productivity. If we don’t
want growth, we can easily imagine a stagnant economy. That said, most
economies aspire at a growth in welfare. We can do this by designing
new products or by material investments or by creative ways to
reorganise production. [104] Then the problem returns of optimising
investments that define real savings. Since some sections of the
economy are devoted to investments, there is also the Keynesian
phenomenon that investments influence activity, income and nominal
savings.
The paradigm to ‘minimize’ the role of government in investment was
misguided since the relation between growth and employment was
misspecified. Now that we know that the tax void was the main cause of
stagflation we can reconsider the paradigm. The argument that remains
is that government meddling supposedly caused failed investments. The
answer to that argument is (i) that failures must be judged on a
case-by-case manner, by Cost Benefit Analysis, and (ii) that one should
include the concept of Keynesian recession and that some investments
might seem a failure but actually are beneficial. Note that there is no
need for a government deficit since the analysis on the dynamic
marginal rate shows that progressive taxes need not be a drawback for
the richer. If growth is the issue, then the true issue is its
optimality in terms of level and composition and effects.
The line of thought that I would suggest is that this optimum requires
competing investment banks that develop plans during the economic
upswing that can be implemented during the economic downswing. Who
worries about pensions and the EU Lissabon Strategy is advised to
consider this approach. Since the market is an anonymous beast that may
or may not generate such competition, it remains the challenge for
governments to mastermind and manage it all.
Book VII
Social Choice
33. Introduction
Kenneth Arrow (1950, 1951, 1963) presented an Impossibility Theorem in
which he showed that decisions about ‘the general welfare’ are
impossible in certain cases or have to be left to a dictator. Arrow
presented some five axioms that each seemed reasonable when considered
by itself, and he argued as well that these axioms are morally
desirable and fitting to the concept of ‘general welfare’. He also
formulated the problem in general terms so that it concerns choices on
goods or people. Subsequently, he derived a contradiction. This result
caused quite some consternation, but eventually the mathematical rigour
caused acceptance, and since then the Theorem forms the core of many
books, such as Sen (1970) and Mueller(1989). The Theorem was also one
of the reasons to award Arrow the Nobel Prize in economics.
A voting example is given by the US Presidential election of 2000.
Apart from the problems around the ballot process itself, there was a
more basic problem: with main contenders Bush, Gore and Nader, Bush got
elected, but in another system, such as a run-off between the two
‘major’ contenders, the Nader vote apparently would have switched
largely to Gore, making him the US President. So the choice depends as
much upon the system chosen as on the preferences. Can we find a
generally good system ? Arrow’s Theorem suggests ‘No’.
Arrow’s Theorem has had a huge influence on scientific and political
thought. Part of this influence is subtle, where skepsis arises about
the concept of ‘democracy’. That shiny goal loses its appeal when we
don’t know how representatives should be elected and when morally
desirable rules would be impossible. Opting for the natural forces in
the social process may be more pragmatic. The influence of the Theorem
can sometimes be more explicit. Next to the model of the utility
maximising individual, there is the model for society as a whole and
then the maximisation of a Social Welfare Function (SWF). But when a
morally acceptable SWF is impossible, what would be the use of research
into such an inherently flawed concept ? Many nations co-ordinate their
economic policy, and have created institutions for this, like the
Council of Economic Advisors (US), the Commissariat du Plan (France),
the Sachverständigenrat (Germany), and the Central Planning Bureau
(Holland). Such an institution, given its role in the co-ordination of
economic policy, could be expected to do reseach on the national SWF.
However, those institutions tend to abstain from that kind of research,
pointing to Arrow’s Theorem as one of the arguments, if not the major
argument.
Over the years an ‘accepted view’ has grown in economics concerning the
meaning of Arrow’s Theorem. This accepted view however has also implied
a kind of moral stagnation.
There are two main reasons to reconsider the accepted wisdom on the
meaning of the Theorem and to rekindle the debate on it. The first
reason is destructive, since it rejects Arrow’s position; the second
reason is constructive, since it provides an alternative.
These reasons are: (1) There is a distinction between the mathematical
framework on one hand and its interpretation on the other hand. The
Theorem holds, and the impossibility holds for Arrow’s axioms, but the
questions of reasonableness and moral desirability are of a different
kind. (2) The area of application of Arrow’s axioms seems rather
static, while reality is dynamic. By considering the role of time,
there is more scope for morality, and then one can identify a voting
procedure that many would find attractive.
The two following chapters develop these arguments subsequently.
Readers interested in more details are referred to Colignatus (2001),
“Voting Theory for Democracy”. That book develops the theory of direct
single seat elections from the bottom up while it also provides
programs (in _Mathematica_) to eliminate the tedious work of the
calculations of the various voting procedures.
34. The solution to Arrow’s difficulty in social choice
Summary
Arrow’s Theorem holds that no constitution can satisfy certain
properties. In annex to that theorem, Arrow claims that those
properties are reasonable and morally desirable. In Arrow’s view there
thus is the difficulty that people desire a constitution that cannot
exist. While the Theorem stands as a mathematical result, the
additional claims concern some other matters, namely the domains of
reasonableness and morality. It are these claims that have caused much
confusion in the literature. It is shown here that the claims are
unwarranted, since inconsistent properties are neither reasonable nor
morally desirable. It is shown too that Arrow’s axiom of Pairwise
Decision Making (formerly known as the Independence of Irrelevant
Alternatives) is not realistic, and thus unattractive. We show the
existence of some constitutions without that axiom that are consistent
and might be optimal to many. The major error made by Arrow and his
students is to mix up the context of scientific discovery and learning
with the context of application to the real world by educated people.
Introduction
Arrow (1950, 1951, 1963) showed that if certain properties are
postulated for a constitution, then such a constitution would not
exist. This result has been checked by numerous scholars, is accepted
by this author, and thus stands as a mathematical theorem. In fact, we
will give a short proof below.
Arrow also claimed, annex to the theorem, and_ this_ will be at issue
here, that those properties would be reasonable and morally desirable.
He recently repeated that claim in the Palgrave (1988:125). He writes:
“(...) conditions to be imposed on constitutions (...)”
“(...) there is no social choice mechanism which satisfies a number of
reasonable conditions”.
For clarity it is useful to introduce the following abbreviations for
the theorem and its companion claims, and their conjunction:
_AT _ = the Arrow Theorem
_ARC_ = the Arrow Reasonableness Claim = the properties are
_reasonable_
_AMC_ = the Arrow Moral Claim = that they are _to be
imposed_
_ AGV _= the Arrow General View = _AT & ARC & AMC_
Note that Arrow’s phrasing on _ARC_ and _AMC_ is a bit ambiguous. The
“to be imposed” might not be moral but merely logical, in a sense that
one needs at least some conditions to make a constitution. However, the
topic of collective choice is distinctly a moral one. Secondly, Arrow
emphasises what is to be imposed and what is reasonable, but he may not
be in a position to impose his views and morals on us. The best
interpretation of the situation likely is as follows. Presume that
Arrow sees the Founding Fathers at work. He then retreats to his
office, and conjectures: ‘If I interprete correctly what they want,
then it are these properties.’ Thus the _ARC_ and _AMC_ are not quite
Arrow’s personal ideas. Above quotes can best be interpreted as factual
statements on what people apparently want and consider reasonable.
Arrow’s general view has been accepted in many places in the literature
and textbooks, see Luce & Raiffa (1957), Johansen (1969), Sen (1986) or
various other entries in that same Palgrave. For example, Tobin (1990):
“We know there is no way to aggregate individual preferences into
social rankings (...). As if this were not obvious, Kenneth Arrow
proved it rigorously years ago. The impossibility applies to
aggregations across contemporaneous cohorts, a fortiori across
generations living and unborn.”
In a much used book on Cost-Benefit Analysis (CBA), A.K. Dasgupta &
D.W. Pearce (1980):
“(...) no escape route (...) seems yet to be available.”
Apparently feeling that Arrow's argument destroys the foundations of
CBA, they find themselves forced, rather grudgingly, to reduce CBA to
something like information gathering.
In an otherwise recommendable volume of Statistical Science, Gill &
Gainous (2002) find:
“In fact, he proved that unless one is willing to violate one of a set
of reasonable democratic norms, (…inconsisteny...) is an inevitability.
(…) Therefore, collective social decisions cannot yield a truly
democratic system in this sense.”
Jorgenson (1990), once president of the Econometric Society, concludes
‘more positively’ to dictatorship:
“The classic result of social choice theory is Arrow’s (...)
impossibility theorem, which states that ordinal noncomparability of
individual welfare orderings implies that a consistent social ordering
must be dictatorial, corresponding to the preferences of a single
individual.”
Not everybody falls for dictatorship. The impact of the _AGV _generally
comes from the fact that people find themselves, either from moral
obligation or from reasonableness, wanting the impossible. And many
simply stay in that fixture.
Note the subtlety in that fixture. The impossibility is logical and not
just empirical. An example may help. Let me confide that I want to
found a new university on the island of Crete. However, I am not that
rich, so I want something impossible. This however does not put me into
a fixture, since I am used to the fact that I cannot afford some things
that I want. However, the Arrow general view concerns a logical
impossibility, which is something quite different.
We can usefully recognise:
reasonable = rational & realistic
Reasonableness is the intersection of rationality and empirical
realism. Nonexistence may derive from empirical circumstances or from
logical impossibility. Irrationality however is always unrealistic.
Inconsistency cannot _exist,_ in the true empirical sense. For example
a round square cannot exist. The nonexistence of the Arrowian
constitution similarly derives not from empirical reality but from
logical necessity.
Given the _AGV_, the question arises what the reasonableness and moral
presumptions of Arrow’s claims actually are. Are these claims as strong
as conjectured ?
My position is as follows:
1. As has been said on ‘round tables’, it is not rational to
postulate inconsistent properties. People involved in a learning
process may indeed make inconsistent assumptions. However, once the
inconsistency is discovered, it is no longer considered to be rational
to adopt those assumptions. People may enjoy ‘roundness’ and
‘squareness’, but having both simultaneously is seen to be
inconsistent, even inconceivable, and hence unreasonable. The Arrowian
properties are unreasonable in the exactly same manner. Arrow’s pitfall
is to confuse the learning process, his context of discovery, with real
world applications by educated people.
2. Similarly, one cannot be morally obligated to a logical
impossibility. Hence Arrow’s properties are morally undesirable.
These points will be clarified below.
Note that people have in practice rejected some of Arrow’s properties.
Even those scholars who seem to accept the general claim _AGV_, accept,
a fortiori, the implied inconsistency, and thus in practice drop some
assumptions to cope with the real world. Unfortunately, however, the
literature has not converged to some agreement on which properties are
best to drop. The position of this paper will be to forward the
proposition that the Arrow axiom of Pairwise Decision Making (formerly
known as the Independence of Irrelevant Alternatives) is the culprit to
kill. It is a bad axiom for rational collective decision making, since
it appears to be incongruent with that very notion itself.
In the following we develop the concepts, give a short proof and
discussion of Arrow’s Theorem, construct the argument against the
claims, reappraise the literature, and conclude.
Basic concepts
Please note that we will have to redefine some symbols for this chapter
only.
Let _X _be the commodity domain. An element in the commodity domain can
be called an item or a candidate. An agent is a compound of various
properties such as utility, wealth etcetera. Let _S _be the set of
possible compounds on _X. _ With _n _agents, our interest concerns the
function _c: Sn S. _which maps the society into an aggregate
compound. This is generally called the ‘Arrow type of social welfare
function’ or simply a constitution.
A constitution differs from the ‘Bergson-Samuelson type of social
welfare function’ (SWF) - and the latter is defined directly over _X
_as _SWF: X _[0,_ _ ).
Arrow’s Theorem concerns Social Welfare Function Generating Mechanisms
(SWF-GMs) like the _c _above. Thus, a constitution can be seen as a
mechanism that uses the population as input and generates a SWF that
orders all elements in the commodity space. This can be compared to a
Social Decision Function (SDF) that selects only one element, namely
the best of a budget set. This can be weakened further by considering
preference orderings instead of functions. Constitutions generally
associate better with SDF-GMs since parliaments generally don’t care
ordering all proposals. However, these concepts can be translated into
each other via varying the budget set. Since the SWF is the
conventional concept in economics, the word “constitution” can remain
associated with a SWF-GM.
It suffices to restrict _S _to preference orderings_. _These orderings
satisfy reflexivity, transitivity and completeness. It is important to
add that there is no cheating. Let _R _denote normal preference, _P
_strict preference, and _I _indifference. When there is no confusion,
we can also use the symbols , < and =. A suffix denotes an individual
preference, otherwise it is the aggregate. An element in _Sn _is called
a _profile,_ and_ R = c(R1, ...Rn)._
There are the following Arrowian axioms:
_ AWP_ the weak Pareto principle
_ AU_ universal domain (wide ranging preferences)
_ AD_ no dictator
_ APDM_ pairwise decision making (the axiom
f.k.a. independence of irrelevant alternatives)
_ a AWP & AU & AD & APDM._
The Arrow Theorem can be expressed in various equivalent logical forms:
_ AT a falsum_
_ AT’ a ~a_
_ AT” ~a_
_ AT”’ _(_AWP & AU & APDM_)_ ~AD_
with _falsum_ a contradiction or falsehood and ~ the negation sign. If
something leads to a contradiction, then we conclude to the falsehood
of the assumptions themselves.
There is a Kantian distinction between technical, pragmatic and moral
(categorical) imperatives. Utility, as commonly regarded by economists,
likely is of the pragmatic kind. Interestingly, theorists on morality
have developed something called ‘deontic logic’, which appears to give
many similar results as economic theory. Deontic logic however applies
to_ propositions_ and not to _commodity domains_. It is possible,
though, to integrate all these kinds of preferences into an integral
utility index, when we replace a point _x _in the commodity domain by a
statement “The state of the world is _x_”. This integral utility index
likely would be lexicographic, in that some moral and constitutional
issues might dominate pragmatic results in the commodity domain. Thus,
while we would use the same symbols _R, P_ and _I,_ we would need to
look into the structure of the index to find the Kantian distinction as
made by the particular agent. We conclude that we can usefully
introduce and apply some terms from deontic logic. Define:
_Ap _(_~p _ _ p_)_ _means that _p _is allowed (at least as good as
_~p_)
_ Op _(_~p < p_) means that _p _is a moral obligation (one ought to
_p_)
An exemplaric deontic result is:
_ Op ~(A(~p))_
Deontic logic allow us to translate:
_ AMC = Oa_
The use of deontic logic allows a forceful restatement of Arrow’s
difficulty in social choice:
_Oa & ~a_
Let us consider some more properties of morality and deontic logic.
The gap between Is and Ought (_Sein und Sollen_) means the rejection of
_p_ _p Op _(‘If something is, then it should be like that’) and, in
principle, _p Op p_ (‘what ought to be, is achieved’).
Note what this actually means. A statement _p _has a truthvalue 1
(true) or 0 (false), depending upon the state of the world. A statement
_Op _has a ‘truthvalue’ 1 (ought) or 0 (not-ought) depending upon one’s
preferences. Applying the logical calculus for the propositional
operators , ~, ,_ & _thus is a mental exercise, where empirical and
preferential statements are first given the common denominator of
‘accepting as valid’. Also, it may be that in one case both _p _and _Op
_are accepted, but the rejection of _p_ _p Op _means that it is
rejected as a _rule_. [105]
Moral consistency is reflected in the Deontic Axiom:
_ DA p,q_ (_Op & _ (_p q_))_ Oq_
There is some discussion between moral theorists whether _DA_ really
holds. It may be felt that the logic is not very compelling for
empirical relations of dubious causality. However, if _p q _reflects a
logial truth, then _DA_ is commonly accepted.
On reasonableness, it seems a bit better to attach the properties to
the agents rather than to the propositions or commodities. Useful
axioms then are:
_ AF _feasibility, _X _is the budget set (rather than
the whole space)
_ ARe_ agents are realistic (they only consider
feasible options, accept _AF_)
I thus agree with Arrow’s 1950 statement: “My own feeling is that
tastes for unattainable alternatives should have nothing to do with the
decision among the attainable ones; desires in conflict with reality
are not entitled to consideration.” Thus, also, when one point is
(socially) most preferred, it is the one consumed.
The most complex property seems to be good old _rationality_. It
appears that we better introduce the information set or knowledge base
_I(.) _and state the condition that it must contain the Arrow Theorem.
Then:
_ARa_ agents are rational (they accept logic, [106] have a
preference ordering, are morally consistent (_DA_), and are educated on
Arrow’s Theorem (_I(~a)_))
The _I(~a) _condition is a novel aspect, that, however, should not come
as a surprise, given what we said in the introduction. There is a
difference between a learning process and a result. In a common
classroom or used-car-salesman strategy, people are goaded into buying
some axioms as reasonable and attractive, and then burn themselves,
which teaches them. This may be called rational from the viewpoint of
learning. This paper however concentrates on the
after-learning-rationality, the kind of rationality that makes learning
so worthwhile.
How does Arrow’s original approach relate to the inclusion of _I(~a)_ ?
Arrow (1950, 1951, 1963) has no incorporation of learning - though he
later has written on ‘learning by doing’ - so it might be that he
assumes standard economic rationality. If that would be perfect
foresight, then _I(~a)_ is implied. However, it is better to hold that
Arrow in that period discussed constitutional choice _for_ agents and
not _by _agents. The choice for people then is made by some algorithm
or calculating machine. His axioms do not describe educated people
involved in constitutional choice. Alternatively put, another new
result in this chapter is the widening of the scopes of utility and
rationality to the inclusion of knowledge about the constitutional
process itself. In that sense the original Arrowian axioms can be
called incomplete. Alternatively, if the idea is that these axioms
concern educated people, then there is a hidden inconsistency, in that
reasonable agents are assumed to regard inconsistent axioms as
reasonable. [107]
Hence:
_ARC = ARe & ARa_
Restatement of Arrow’s Theorem
It appears very useful to discuss the example given by the Marquis de
Condorcet 1785. Sen (1970) gives a simple example that appears to be
presented first by Nanson 1882. A similar example is reproduced in
Table 12, and I will refer to it as “the Condorcet case”. There are
three parties and three topics _A, B _and_ C_ on ballot, and the
numbers of seats and the preferences are such that, with pairwise
voting and a majority rule, a cycle results: _A < B < C < A_.
Table 12: Condorcet 1785
_Party_
_Seats_
_ _
_Topics ordered by preference_
_ _
_Pairwise vote_
Low
Mid
High
_A_
_B_
_ _
_B_
_C_
_ _
_C_
_A_
Red
25
_A_
_B_
_C_
25
25
25
Green
35
_C_
_A_
_B_
35
35
35
Blue
40
_B_
_C_
_A_
40
40
40
_Total_
_100_
_40_
_60_
_ _
_35_
_65_
_ _
_25_
_75_
_B_
_C_
_A_
It is, in all clarity, not that easy to aggregate votes on more than
two topics. [108] For two topics one can indeed ask for pro and contra,
and find a majority (and occasional ties, for which exist tie-breaking
rules). For two topics one can indeed ask for pro and contra, and find
a majority (and occasional ties). For more topics, votes will scatter
across the topics, and there will often be no clear majority. Therefor,
pairwise voting is a good strategy to get the required information on
the preferences. However, pairwise voting apparently also causes
problems. So, basically, the search is for a strategy without such
problems. And that is, basically, also the suggested value of Arrow’s
Theorem: that it states that there would be no such good strategy.
However, in this Condorcet example, we may clearly conclude that the
cycle primarily means that there is a tie. The situation is in a
deadlock, and the group, as a collectivity, is _indifferent_. That
there are indifferences or ties, is nothing special. Standard economic
analysis allows agents to be indifferent (we even draw indifference
curves), so groups should be allowed to be indifferent too. In
Condorcet’s example, indifference is even a logical choice, since when
we assume something else, then we quickly run into difficulties.
There is the famous case of Buridan’s Ass (AD 1358). A donkey stands
between two equal stacks of hay, at equal distances. He cannot decide
which stack to take, and dies of starvation. The upshot of this parable
is that rational beings can devise a decision. Constitutions generally
state what happens when there are ties. Commonly the Status Quo
persists. (This may happen even if it was one of the topics under
ballot, and apparently was rejected at that stage.) Alternatives are
that the chairman decides, or points are (re-) negotiated, and one can
use dice.
It is important to see the difference between _voting_ and _deciding_.
In two stages, the chairperson first lists the votes, and then only
secondly gives the decision with a tick of the hammer. Table 12
essentially gives a voting field, and no decision yet. There is no
inconsistency as long as we record these results as voting scores, for
example “_B_ has more votes than _A_ in a pairwise comparison”. There
only arises an inconsistency when we change this into a preference,
i.e. decide that “_B_ is better than _A_”. There are additional rules
that translate the field into a unique decision. Part of paradoxical
element in voting derives from confusing voting and deciding.
We can use Condorcet’s example to give a short proof of Arrow’s
Theorem, restricting our attention to majority voting.
Proof: The group decision in the Condorcet case is indifference, so
that _B = C_. Under the axiom of universality we can look at various
preference _profiles_, of which Condorcet’s example is only one. Now
regard the adjusted profile such that the preferences on _B _and _C_
remain the same, but the preference on _A _drops to the lowest
position. The new profile thus is _{A < B < C, A < C < B, A < B < C}._
Since the preferences on _B_ and _C _have not changed, the _APDM_
outcome on _B_ and _C_ should be the same. Majority voting now however
results into _B < C _which differs from _B = C_. Contradiction. Thus
there is a counterexample to the axioms. So the axioms are
inconsistent. Q.E.D.
The merit of this short proof is that it clearly shows the awkwardness
of the _APDM._ In the case of Condorcet’s example the conclusion _B =
C_ is a sound decision, and in the case of the adjusted example the
conclusion _B < C_ is sound too. That preferences outside of the pair
_B _and _C _ have changed is_ vital_ to the group decision, since the
shift helps a change from clear indifference to clear preference. The
preferences on other topics are quite relevant, and not ‘irrelevant’.
_APDM _excludes vital information about the preferences - to be
precise: it destroys information that exists - and it should come as no
surprise that paradoxes and inconsistencies arise. The _APDM _is
incongruent with the notion of group decision making. Perhaps an
individual can exclude information about other topics, but a group
cannot. (Or a brain that works as a group cannot.) It is a surprise
that _APDM _has not been killed right in 1951.
A note on the name of APDM
Arrow (1951, 1963) introduced an axiom “Independence of Irrelevant
Alternatives” (_AIIA_) that has caused much misunderstanding. That
axiom here has been baptised the “Axiom of Pairwise Decision Making”
(_APDM_). Thus the axiom remains the same, only the name is different.
The new name is much clearer about what the axiom really means in
normal English.
Since the name “IIA” is so entrenched in the literature, this change of
name requires some explanation. The explanation is along the lines:
· There is the distinction between voting and deciding.
· Items that cause cycles cannot be called ‘irrelevant’ for decision
making.
· The criterion to separate the relevant items from the irrelevant ones
is rather the budget and is not necessarily found in pairwise voting
for all items.
Arrow's axioms on using the whole commodity domain and universal
preferences introduce the possibility that we might also be obligated
to consider farfetched items. Arrow introduced the _APDM_ to limit this
effect again, since it allows that a decision on our current issues can
be taken independently from other farfetched possibilities. It is
reasonable that people neglect farfetched possibilities. Thus Arrow on
one hand opens the door wide for such farfetched possibilities, and on
the other hand introduces a strict condition that kills the relevance
of this. The whole looks reasonable, since people in fact neglect
farfetched possibilities.
Yet, the whole does not conform with the practical situations in
Parliaments, where the problem is defined for existing voters and where
the issues on table are given by the budget set.
Thus, (a) the notion of ‘irrelevance’ is dealt with by considering the
budget set, (b) the axiom can be named after what it properly does:
pairwise decision making.
If we want to deal with possibly farfetched preferences of some
citizens, which is the moral meaning of the axiom of universal
preferences, then we should work towards practical procedures that
work. Assuming inconsistent axioms is not a good way to deal with that
moral question.
The following sections use formal logic.
A lemma
Lemma A.I: _AF_ implies that a constitution _p_ satisfies the property
_Op p_.
First proof: _AF _means that desires (_Op_) in conflict with reality
(_~p_) are not entitled to consideration. But _p_ _~(Op & (~p)) _is
equivalent to _p Op p_. Q.E.D.
Second proof: We already concluded that the most preferred point (_Op_)
would also be the chosen point (_p). _Thus _p_ _Op p_. (If the point
is not preferred, then the implication is true _ex vacuoso._) Q.E.D.
Discussion: We have enlarged the commodity domain with constitutions,
and hence the axiom of feasibility becomes a bit stronger. The
extension itself is rather weak, since we only extend on consistency
(and not empirical validity). Our criterion is as that a reasonable
society would stick to its rules. The gap between Is and Ought still
exists in principle, but can in practice be bridged by the human effort
to attain one’s ends.
Rejection of the Arrow Moral Claim (AMC)
Theorem A.1: For a reasonable society, the _AMC_ is invalid.
First proof by rationality & moral consistency (_DA_): Assume _Oa. _But
_a ~a, _and with _DA _we get _O~a. _But this gives a preference
inconsistency _Oa & O~a_. Hence _~Oa. _Q.E.D.
Second proof by rationality & moral consistency (_DA_): Assume _Oa.
_Since _a falsum _we find _Ofalsum. _Thus for some _p_0_ _we have
_O(p_0_ & ~p_0_). _But this means _Op_0_ & O~p_0_, _and that is a
preference inconsistency. Hence _~Oa. _Q.E.D.
First proof by realism (_AF)_: Assume _Oa. _By the lemma _p_ _Op p
_we find _a. _But then we have _~a & a, _which is an inconsistency.
Hence _~Oa. _Q.E.D.
Second proof by realism (_AF_): Since _~a _ and above lemma _~a ~Oa,
_hence _~Oa. _Thus the axioms are not morally desirable either. Q.E.D.
Note: _q p _is equivalent to _~p ~q, _and we may take _q = Op._
When the axioms would be morally desirable, then the derived
contradiction would be morally desirable - but nobody can be asked to
do the impossible. Hence the axioms are not morally desirable. This is
a seemingly simple reasoning scheme, but destructive to the accepted
view.
Rejection of the Arrow Reasonableness Claim (ARC)
Theorem A.2: For a reasonable society, the _ARC_ is invalid.
Proof: Given _AF_, infeasible choices are not considered. Since _~a,
_apparently _a _is not feasible, and the Arrow constitution is not
reasonable. So it is invalid that the axioms would be reasonable.
Q.E.D.
Discussion: As we stated above, we have enlarged the commodity domain
with constitutions, and hence the axiom of feasibility becomes a bit
stronger. The extension itself is rather weak, since we only extend on
consistency (and not empirical validity). But the conclusion is strong.
No reasonable society in its right mind would want to accept Arrow’s
axioms as its constitution. Supposedly at a chaotic Boston Tea Party a
constitution _c = a_ might be tried, but pretty soon rational people
would see that they should make another constitution, for otherwise the
situation will remain chaotic, and the Tea Party will not go down into
history as a notable event.
Note that Arrow adopts feasibility, but also wants to impose infeasible
conditions.
When Arrow’s axioms would be reasonable, then they would have to be
consistent as well. However, they are inconsistent. Thus they are not
reasonable. This seems a rather simple scheme of reasoning, but it
destroys the impact of the Theorem.
For the axioms, there is the subtle difference between ‘reasonable’ and
‘seemingly reasonable when considered by itself’. The following is a
good analogy. For a bicycle we want round wheels for when it rides. For
a bicycle we also want square wheels, so that it does not fall when it
stands still. But there are no round squares ! Ergo, conditions that
seem reasonable by themselves, create something impossible and
decidedly unreasonable when combined. To conclude ‘there is no good
bike’ would however be absurd. Admittedly, it is a good teaching method
to first convince students that something would be reasonable, and then
have them derive a contradiction. As with the buying of a bad
second-hand car, the students learn to be careful, and they learn a
respect for science and the value of modesty. This teaching method
however overshoots when people remain believers of the reasonableness
of the assumptions - as apparently happened with the assumptions of
Arrow’s Theorem. A paradox is only a seeming contradiction. Thus there
must exist a system that we are willing to accept as the optimal one.
Many mathematicians have been sensitive to the distinction between
‘reasonable’ and ‘seemingly reasonable when considered by itself’, but
the literature also abounds with instances where this distinction is
not applied with sufficient care. Part of the accepted view thus is a
case of bad communication of the incrowd with the larger public. (Given
above quotes, the incrowd however might be small. Quis custodet
custodes ?)
Selection of the culprit axiom.
The selection of the culprit axiom is straightforward. We order the
axioms by preference, for example _AD > AWP > AU > APDM. _From _~a,_ we
conclude that we have to drop one of the axioms. We drop the least
preferred one. My discussion on Condorcet’s example should generate
support for the rejection of _APDM. _Basically though, scientists can
only advise on preferences, and the proper decision is up to the body
politic.
Lemma A.II: If all agents have _a > APDM_ then, with _AWP_, society
has [_AU, AWP, AD_] > _APDM_. Note: here [_x, y, z_] means the
unordered set.
Proof: _obvious_.
Discussion: When all people put _AU, AWP_ and _AD_ in any individual
order, but all would have _APDM_ below these, then society can reject
_APDM _unanimously. In fact, the condition _AU_ might as well be
regarded as part of the _definition_ of a SWF-GM, and similarly, _AWP_
could as well be regarded as part of the _definition_ of the notion of
collective preference. So the real choice concerns _AD_ and _APDM_, or
between dictatorship or not.Here a selfish dictator and his associates
would have _¬AD > APDM > AD_. The Jorgenson quote suggests his
preference for a benevolent and non-selfish dictatorship, but, also
since such dictatorships tend to turn sour, my impression is that he
would eventually be an associate of a real dictator. Most likely, he
did not understand the situation when the quote was printed.
Note that ordering the axioms means that the deontic predicate _O _is
not homogeneous. This means that deontic logic may be more related to
preference theory than deontic theorists think.
Examples of consistent constitutions
Consistent constitutions violate one of the axioms of Arrow’s Theorem.
Violating one of these axioms is to be considered useful for
reasonableness and morality, rather than the reverse. (That is what we
proved above.)
One general feature is a Status Quo that persists when there are ties.
One example already has been mentioned in the discussion of the
Condorcet problem. With majority voting, a cycle means indifference,
and there are various ways to solve ties. One possible solution is the
persistence of the Status Quo._ _
Another example constitution is the “Pareto-Majority” rule. One first
selects all Paretian improvements from the Status Quo. That is, those
points where some advance while nobody loses. There may be more
Paretian points, such as _B > A _and _C > A,_ with the Status Quo as
_A._ When there is no Paretian order between _B _and _C_, then it
suffices to decide on these points by simple majority. Of course, with
more than two points, majority voting can result into cycling, but that
again means indifference, which could be settled by dice, by the
chairperson, or by other creative ways.
See my home page and The Economics Pack for implementation of these
rules in the program _Mathematica_. Little helps so much as a trying it
out for yourself.
A reappraisal of the literature
Our discussion arrives at a conclusion that differs from the
literature, and thus warrants a reappraisal of that literature. This
reappraisal is not the topic of this paper, but some examples are
useful.
(1) Note that the Tobin quote above was misleading. The problem with
‘unborn generations’ should not be mixed up with the Arrow difficulty.
The Tobin problem actually can have a rather simple solution. It are
the preferences of the currently living that matter, and what they
prefer for the future unborn (which can also be based on a forecast of
such preferences). These future preferences cannot logically be
included, since they don’t exist yet.
(2) Arrow 1951 also stated:
“If consumers’ values can be represented by a wide range of individual
orderings, the doctrine of voters’ sovereignty is incompatible with
that of collective rationality.”
This is clearly inaccurate. The statement suggests that we have to
adopt Arrow’s axioms, while the sensible thing is to reject these
axioms and to adopt both voters’ sovereignty and collective
rationality.
(3) One of the more interesting points made here is the distinction
between the learning process and the end result. How should Arrow’s
result be presented in the future ? Is it possible to maintain the
teaching strategy to call the axioms ‘reasonable’, then have the
students get into a fixture, and them let them find a way out ? It is
good teaching practice ! However, in a Palgrave meant for a wider
audience (or a general encyclopedia that even might be read by
dictators), it might be improper to call Arrow’s axioms ‘reasonable’.
It should be ‘seemingly reasonable’ at the least.
Note that the phrase then becomes less enchanting:
‘there is no social choice mechanism which satisfies a number of
seemingly reasonable conditions’.
(4) I am a bit shocked by Mueller’s (1989, p406-407) discussion of
Arrow’s general view. One would expect a more critical attitude, but
finds instead:
“The Arrow and Sen theorems (...) raise fundamental questions about the
possibility of establishing collective choice procedures satisfying
minimally appealing normative properties (...) But the negative side
should not be overemphasized. We have suggested that both sorts of
paradoxes might be avoided with the use of cardinal, interpersonally
comparable utility information. Arrow explicitly eschewed the use of
such information, and the independence of irrelevant alternatives [thus
Pairwise Decision Making / TC] axiom was imposed to rule out voting
procedures that might make use of such information (... But it) is
possible that the citizens may be trusted to make these comparisons in
an ethically acceptable way.”
Well, interpersonal comparison of course occurs, minimally, when we
assign votes to people, assign rights to put topics on ballot, and the
like. So interpersonal comparison is not as bad as many economists seem
to think. But my solution to Arrow’s difficulty does not rely on
cardinality and cardinal comparison. So, disappointingly, Mueller both
accepts the idea that Arrow would cause ‘questions’ about the
possibility of social choice, and he comes with a wildly wrong
conclusion. This is supposed to be a modern textbook !
(5) What is important, is that the development of economic theory and
the development of real economies have been hindered by the confusion
generated by the standard explanation. Where decision makers were
divided, some interested in social welfare and others not, the latter
group was provided with decisive gunpowder - and beware of people who
have an ideology and even wield a mathematical theorem to prove their
lunacy. Generations of students have been taught by Nobel Prize
laureats that research into social welfare would be subject to
impossibilities. Creative energy has been directed to enlarging the
impossibilities rather than to devising structures that might improve
practical situations. Practical research into social choice functions
and parameters has been aborted, all with reference to a misunderstood
theorem !
Economic research also leads to a suggestion of a constitutional
amendment, see Colignatus (1996b) and the appendix. I hope that this
present chapter helps to clarify that this kind of research is a useful
type of economics.
(6) This analysis also clarifies a confusion about the relation of
constitutions to the SWF. While many economists argued that
constitutions could not be reasonable or morally acceptable, they did
accept the Bergson-Samuelson SWF, even though the latter was derived
from the former - and nobody seems to care about this inconsistency.
Which is now removed, since the properties of the constitution are
projected into the SWF.
(7) It is relevant to note that I gave this analysis earlier, in
Colignatus (1990c, 1992a). This chapter is almost 99% the same as
1997b, and a a rephrasing of the main principles. I have had no success
so far in getting a publication, neither at the CPB nor in a journal.
[109]
Conclusion
Arrow’s Theorem has given some problems in the literature, see the
quotes above. We have achieved the following solution:
· There is more clarity now, by the distinction between the theorem
proper (_a falsum_), the moral claim (_Oa_) and the claim on
reasonableness (_AF _and _I(~a)_).
· The arguments above on rationality and morality have a destructive
character since they reject the accepted view. In another perspective
they are constructive, since they allow the formalisation of (meta)
notions, and bring these back into mathematics again (notably the
voting on constitutions).
· From a mathematical point of view, the Arrow axioms are incomplete
for decision making in a reasonable society.
· It has been shown that the _APDM _is undesirable. Dropping _APDM _is
not a sad state of affairs, as is sometimes suggested in the
literature, but a sign of understanding group decision making.
· The Arrow axiomatisation does not capture the truly desirable
properties required for a constitution, both by incompleteness and
_APDM._
· There are detail results, such as the distinction between voting and
deciding, the integration of preference theory and deontic logic, and a
proof of Arrow’s Theorem that shows clearly the abuse by _APDM._
· We have given examples of consistent constitutions that many might
regard as optimal.
Addendum: Sen’s restatement in “Development as freedom”
Sen (1999a:250-253) contains a short summary discussion on his view on
the Theorem. First I quote him and then give my comment. Sen states:
“The Arrow Theorem does not in fact show what the popular
interpretation frequently takes it to show. It establishes, in effect,
not the impossibility of rational choice, but the impossibility that
arises when we try to base social choice on a limited class of
information.”
This is not correct. Using the information provided by pairwise voting
results, we can decide to a tie (deadlock, indifference) when such
might arise. It is the adoption of the _APDM_ axiom that, wickedly,
turns this indifference into an inconsistency. The _APDM_ does not mean
lack of information, it only corrupts the information that exists.
“At the risk of oversimplification, let me briefly consider one way of
seeing the Arrow theorem. Take the old example of the “voting paradox,”
with which eighteenth-century French mathematicians such as Condorcet
and Jean-Charles de Borda were much concerned. If person 1 prefers
option_ x _to option_ y _and_ y _to _z, _while person 2 prefers_ y _to_
z _and_ z _to _x_, and person 3_ _prefers_ z _to_ x _and_ x _to _y_,
then we do know that the majority rule would lead to inconsistencies.
In particular,_ x _has a majority over _y_, which has a majority over
_z_, which in turn enjoys a majority over _x_. Arrow’s theorem shows,
among other insights it offers, that not just the majority rule, but
_all _mechanisms of decision making that rely on the same informational
base (to wit, only individual orderings of the relevant alternatives)
would lead to some inconsistency or infelicity, unless we simply go for
the dictatorial solution of making one person’s preference ranking rule
the roost.”
Locating the problem in the informational base is erroneous. Clearly,
majority decision does _not_ lead to inconsistencies, for it is the use
of the _APDM_ axiom that does so - and we don’t need it for majority
decisions. The Arrow Theorem does _not_ show that there are
inconsistencies for _all_ mechanisms - we namely can use mechanisms
without _APDM_.
“This is an extraordinarily impressive and elegant theorem — one of the
most beautiful analytical results in the field of social science. But
it does not at all rule out decision mechanisms that use more — or
different — informational bases than voting rules do. In taking a
social decision on economic matters, it would be natural for us to
consider other types of information.”
I don’t know about “extraordinarily impressive and elegant”. Condorcet
came up with his paradox, as earlier people came up with paradoxes when
dividing by zero, as Bertrand Russell had his set-paradox, and as the
Cretian Epimenides said “All Cretians are liars.” Arrow’s Theorem
solves the Condorcet paradox by showing that we must not use _APDM_ -
though Arrow apparently did not realise that. The theorem is basic, and
we must be glad that we have it, as _APDM_ apparently can cause a lot
of confusion, as the last 50 years have shown.
“Indeed, a majority rule — whether or not consistent — would be a
nonstarter as a mechanism for resolving economic disputes. Consider the
case of dividing a cake among three persons, called (not very
imaginatively) 1, 2, and 3, with the assumption that each person votes
to maximize only her own share of the cake. (This assumption simplifies
the example, but nothing fundamental depends on it, and it can be
replaced by other types of preferences.) Take any division of the cake
among the three. We can always bring about a “majority improvement” by
taking a part of any one person’s share (let us say, person 1’s share),
and then dividing it between the other two (viz., 2 and 3). This way of
“improving” the social outcome would work — given that the social
judgment is by majority rule — even if the person thus victimized
(viz., 1) happens to be the poorest of the three. Indeed, we can
continue taking away more and more of the share of the poorest person
and dividing the loot between the richer two—all the time making a
majority improvement. This process of “improvement” can go on until
the poorest has no cake left to be taken away. What a wonderful chain,
_in the majoritarian perspective, _of social betterment!”
Remember that Sen writes this book for a general audience of economists
who will not have gone deeper in social choice theory. Though Sen now
relates basic truisms, his reasoning nevertheless is a bit off. Indeed,
Western democracies tend to have property rights and a “status quo”
rule, and a Madisonian philosophy that democracy actually exists to
protect the minorities. We use all kinds of additional information, in
order to settle problems of fairness and equity. Thus the majority rule
is not suggested for the raw form that Sen uses as an example. Then,
crucially, when Sen suggests that this example clarifies that we must
use more information to solve the Arrow paradox, then this is a
non-sequitur. His argument becomes seductive, since the reader is
seduced into thinking that, indeed, we use more information. But the
truth is that we use this additional information to solve equity
matters, and not to solve the Arrow inconsistency.
“Rules of this kind build on an informational base consisting only of
the preference rankings of the persons, without any notice being taken
of who is poorer than whom, or who gains (and who loses) how much from
shifts in income, or any other information (such as how the respective
persons happened to earn the particular shares they have). The
informational base for this class of rules, of which the majority
decision procedure is a prominent example, is thus extremely limited,
and it is clearly quite inadequate for making informed judgments about
welfare economic problems. This is not primarily because it leads to
inconsistency (as generalized in the Arrow theorem), but because we
cannot really make social judgments with so little information.
“Acceptable social rules would tend to take notice of a variety of
other relevant facts in judging the division of the cake: who is poorer
than whom, who gains how much in terms of welfare or of the basic
ingredients of living, how is the cake being “earned” or “looted” and
so on. The insistence that no other information is needed (and that
other information, if available, could not influence the decisions to
be taken) makes these rules not very interesting for economic decision
making. Given this recognition, the fact that there is _also _a problem
of inconsistency—in dividing a cake through votes — may well be seen
not so much as a problem, but as a welcome relief from the unswerving
consistency of brutal and informationally obtuse procedures.”
Sen is aware that his reasoning is not strict (vide his use of
“primarily” and “_also_”) but, still, he makes the suggestion, which is
erroneous.
Indeed, the spirit of “impossibility” is not, I believe, the right way
of seeing Arrow’s “impossibility theorem.” [footnote] Arrow provides a
general approach to thinking about social decisions based on
individual conditions, and his theorem—and a class of other results
established after his pioneering work — show that what is possible and
what is not may turn crucially on what information is taken into
effective account in making social decisions. Indeed, through
informational _broadening, _it is possible to have coherent and
consistent criteria for social and economic assessment. The “social
choice” literature (as this field of analytical exploration is called),
which has resulted from Arrow’s pioneering move, is as much a world of
possibility as of conditional impossibilities. [footnote]”
This quote just repeats the error - and adds a string of perceptions to
sweeten the cake. The footnotes are references to his “Collective
choice and social welfare”, his Handbook contribution and the Nobel
lecture, Sen (1999b), and add no news, for us, to the essence discussed
here. Indeed, the obviously relevant Nobel lecture just repeats the
error.
Hence, Sen basically does not understand the problem. I do value his
work on social choice since it was a useful guide to me in making
Arrow’s result accessible, and in seeing the various perspectives of
it. As Newton is reported to have said: “Standing on the shoulders of
giants, we can look further.” I cannot wait till Sen writes me that he
enjoys my solution !
Addendum: Mas-colell, Whinston and Green, “Microeconomic Theory”
Andreu Mas-colell, Michael Whinston and Jerry Green ’s 1995
“Microeconomic Theory” is just wonderful. A great book. Generally
speaking, though, since they erroneously write: “Either we must give up
the hope that social preferences could be rational in the sense
introduced in Chapter 1 (i.e. that society behaves as an individual
would) or we must accept dictatorship.” (p780). And the subsequent
discussion indeed leads the student in the bogs and misdirections so
typical of 20th century ‘social choice theory’. The math is OK, but
concerns something like the question of how many angels can dance on a
pin’s head - and the whole induces the student to become wary of social
decision making. (To be sure: I appreciate the other qualities, and
have used the book for sections of my Economics Pack.)
35. Without time, no morality
Summary
Theory shows that voting is subject to paradoxes, while it also appears
that a voting result is caused as much by the procedure as by the
voters’ preferences. From a moral point of view, the choice of the
procedure then is the major issue. A key insight is that morality
presumes time. In a static world everything is given and there is no
place for individuals who have to ponder their moral choices. The real
world is dynamic however and the most challenging voting paradoxes
concern budget changes. The paper develops a new “Borda Fixed Point”
mechanism that provides a better protection to surprises by such budget
changes. Under dynamics, Donald Saari’s argument on symmetry is less
convincing.
Introduction
The currently accepted view is sometimes expressed as that ‘there is no
ideal voting scheme’. The former chapter destroyed that view. There is
no mathematical reason to think that such an ideal cannot exist. Since
Arrow’s axioms must be rejected, they do not form an ideal. An ideal
still can exist, but apparently it is different than originally
thought. Perhaps people have different ideals, but then the
non-existence of a common ideal derives from empirically different
opinions and not from mathematical reasons. Since people can benefit
from co-operation, they can still aspire at a scheme that all can agree
upon.
Above analysis does not answer the positive question yet what would be
a generally good system. The main point here is that everyone should
determine this for oneself. Theory can only help to remain consistent.
The following is a suggestion for a scheme that is consistent and that
could appeal to many.
Control of natural forces in the social process
One important idea is that time plays a role. The basis for this idea
is that, abstractly, morality presupposes time. Without time there
would be no morality. In a static world everything is given, and there
is no place for an individual who has to ponder his or her moral
choices. As economists, we can draw static utility functions and
isoquants, but those are abstractions, and they might distract from the
real moral problem. The moral problem is that _now_ a decision has to
be made while the consequences appear _later_. Afterwards, everything
can be explained deterministically (which is the meaning of
‘explanation’), and by hypothesis, determinism will also hold for the
future. Yet, in the mean time forecasts are imperfect, there is
fundamental uncertainty, and that creates the possibility of morality
(or the illusion of morality).
Economic science is intended to help explain reality. In this reality,
we see an evolution of human beings in a social process of natural
forces. The basic concept is power, in a continuous process, so that
the basic approach uses ratio scales and cardinal utility and not
ordinal scales. Other assumptions than cardinality enter the discussion
_only_ when the group wants to control power, and for example introduce
democracy. A common notion is that economists reject cardinality and
interpersonal comparison of utility. However, the concept of ‘one
person, one vote’ actually imposes some interpersonal comparison of
utilities. Also comparing orderings of preferences implies some
comparison of utilities. The proper perspective is rather that
cardinality is deficient since people can cheat about their preferences
(at least in the current state of technology). The major argument for
ordinality is that it limits the room for cheating. If people could not
cheat, interpersonal comparison likely would be much more popular
amongst economists. The point that ordinality reduces interpersonal
comparison thus seems less relevant than the point that cardinal
comparisons are unreliable since people can cheat.
For example, when a family goes on holiday and has the choice between
Spain or Greece, then little Robby might exaggerate his preference for
Greece and say that he might as well die when Spain is selected. When
the aggregation of preferences would be cardinal, such a huge negative
weight for one option would certainly block it. Imposing ordinality
limits the impact of cheating however. In common textbooks on voting
theory, cheating comes in relatively late, but it is more adequate to
start right away with that notion. The crucial insight is: Arrow’s
Theorem and the voting paradoxes are the price that we have to pay in
order to limit that impact of ‘stategic’ voting behaviour.
Arrow’s orginal question whether there could not exist a generally good
voting mechanism remains a valid question, though. As history has
shown, mathematicians are proficient in identifying paradoxes and in
deriving new impossibilities, and one will not quickly find a
suggestion for a generally good system. But it appears that when we
consider the issue of time, then a solution tends to suggest itself. To
understand this solution, it is useful to first consider three main
contenders, i.e. the ‘traditional’ solutions provided by Plurality,
Borda and Condorcet. There are other methods, but their properties are
such that they need no consideration here.
Three traditional methods
In Plurality, all voters have one vote, and the candidate with the
highest number is selected. Note the problems with this method. The
criterion of ‘highest number’ does not imply that the winner must also
have more than 50% of the vote. If this is additionally imposed, then
this may require more rounds of voting, and then there is the difficult
issue whether candidates have to drop out, and if so, how.
Borda’s method is to let each voter rank the candidates by importance,
then assign weights given by the rank position, to add the weights per
candidate for all voters, and then select the candidate with the
highest value. Note that the method appears sensitive to preference
reversal, see below.
Condorcet’s method is to vote on all pairs of candidates, and to select
the one who wins from all alternatives. Note that such a “Condorcet
winner” does not need to exist. In that case the margins of winning can
be used to solve the deadlock - but this increases the sensitivity to
who participates.
The following example is taken from Saari (2001ab). Consider a budget
of three candidates _A, B_ and _C,_ and let there be 114 voters. When
we neglect indifference and use strict preference only, then with 3
candidates there are 3! = 6 possible ways of ranking them. Table 13
contains an arbitrary allocation of those voters over such preferences.
The highest ranking candidate gets rankorder weight 3, the second gets
weight 2, and the least preferred candidate gets weight 1. In the table
we can read for example that there are 33 candidates with preference _A
> B > C_.
>
>
Table 13: Voting example
_Number of voters_
_Candidates and their rank order weight_
_Sum _114
_A_
_B_
_C_
33
3
2
1
0
3
1
2
25
2
1
3
17
1
2
3
14
1
3
2
25
2
3
1
_ Results of the procedures_
_Mostly preferred_
33+0 = 33
14+25 = 39
25+17 = 42
_Borda_
230
242
212
_Pairs: A vs B_
58
56
-
_ A vs C_
58
-
56
_ B vs C_
-
72
42
The different voting schemes result into different decisions:
1) Plurality: Voters give one single vote to the candidate of
their highest preference. For candidate _A_ we consider its column,
select the rows with the score 3, and add the associated numbers of
voters 33 + 0 = 33. And so on. Candidate _C_ gets most votes, namely
42.
2) Borda: The votes are weighted with the rank order weight. De
column for _A_ is multiplied row by row with the number of voters 3 *
33 + 3 * 0 + 2 * 25 + … = 230. Candidate _B_ gets most votes, namely
242. (Scores -1, 0, 1 might calculate easier.)
3) Condorcet: Voting pairwise over _A_ versus _B_, there are 33 +
0 + 25 = 58 voters who give _A _a higher rankorder than _B. _Etcetera.
Candidate _A _appears to win from both _B_ and _C_, and then is the
“Condorcet winner”.
This example shows that _A, B_ and _C_ can _all_ be winners, depending
upon the method selected. The properties of the methods then are the
true issue.
Above still neglects strategic voting. This could be represented by a
change in apparent position. How do we evaluate this ? It appears that
the Condorcet approach is least sensitive to cheating since in a
pairwise vote there is an incentive to express one’s true preferences.
Pairwise voting however can be unattractive since there need not be a
Condorcet winner, or, when one exists, it may conflict with the
preference rankings. One way to solve the complexity of choosing
between these methods is to compromise by having a run-off election.
The two top outcomes of Plurality or Borda are taken and then subjected
to a pairwise vote as in Condorcet. There is one final consideration.
Simply taking the two ‘top outcomes’ seems unduly simple, we should
consider what these actually are. In France, the election between
Chirac, Jospin, Le Pen and others caused Jospin’s votes to scatter over
all kinds of smaller parties so that he dropped from the race while he
was the Condorcet winner of both Chirac and Le Pen. When we are
compromising, we should focus on determining the two main contenders.
Borda Fixed point
Let us reconsider the dynamic process that occurs within an economy. We
see that under the influence of time, the budget changes continuously.
A voting scheme naturally requires that there is a list of candidates,
but one cause for paradoxes is that that list is not fixed. For
example, in the Borda vote above_, B_ is selected, but if _C _decides
to withdraw (or gets a heart attack), then we would expect _B _to
remain the winner, but suddenly it is _A_ (see the Condorcet vote _A_
versus _B_). Remember also the Bush, Gore and Nader case. We could
consider a procedure to be better when the choice is less dependent
upon changes in the budget.
A way to achieve this is to use the notion of a ‘fixed point’. For a
function _f: D R_, for some domain _D_ and range _R_, the point _p _is
a fixed point iff _f(p) = p_. Let us consider this concept for voting.
Let _P _be the voting procedure, and let _X_ = {_x_1, …, _xn_} be the
budget with all the candidates. Let the unrefined winner be _w_ =
_P_(_X_)_. _Let _Y _be the budget when _w_ does not participate,_ Y_ =
_X_ \ {_w_}. Let the ‘alternative winner’ be _v_ = _P_(_Y_) = _v_(_w_),
i.e. the candidate who wins when the first winner _w_ does not
participate. This is not simply the run-off between the winner and the
common runner-up, since the selection of the alternative winner
requires the recalculation of the preference weights. This alternative
winner can be seen as a ‘summary’ of the opposition to _w_. The scheme
is a compromise since the Condorcet pairwise condition holds for the
winner and the alternative winner. While these notions are defined with
respect to the unrefined winner, we can generalise this to any winner,
and in particular to our optimal winner.
An alternative condition for winning in general is the ability to win
from one’s strongest opponent. This gives the fixed point condition.
Define _f_(_x_) = _P_(_x, P_(_X_ \ {_x_})), which is the general
function ‘the vote result of _x _and its alternative winner’. Then _w*_
is the solution to the fixed point condition _x_ = _f_(_x_):
_w* = P_(_w*, v_(_w*_)) =_ P_(_w*, P_(_X_ \ {_w*_})) = _f_(_w*_)
When the unrefined winner _w _is not a fixed point, i.e. when the
unrefined winner _w_ = _P_(_X_)_ _appears to lose from _v,_ so that _w
P_(_w, v_), then the search process can start again from _v. _
It appears that this fixed point voting procedure reduces the
dependence upon budget changes. There can still be a dependence, but it
is not as large as without the condition.
In Table 13, the Borda Fixed Point winner is _A_. With _B_ the Borda
winner, _A_ is the alternative winner when _B_ does not participate,
and _B_ loses from _A_ in a pairwise match; starting the search from
_A_, its alternative winner is _B, _and _A_ wins from _B_.
More on this can be found in Colignatus (2001). That book has also been
intended as a textbook and it developed _Mathematica_ programs for the
various voting schemes and data manipulations. Given the complexity of
the matter, this working environment has appeared a great advantage.
Relation to Saari’s work
Donald Saari (2001ab) showed that Borda’s method is the only method
that satisfies certain symmetries. His suggestion is that the Borda
rule ‘therefor is best’. This argument does not convince by itself
since ‘symmetry’ is not by itself a moral category. Dynamics is linked
to morality, by the notion that morality presumes time, and thus seems
a better angle.
Consider direct symmetry first. Suppose that your preference is _A > B
> C_ and that my preference is _C > B > A_. The direct symmetry
consideration is that we might both abstain from a vote and stay home,
since our preferences strictly oppose each other. Saari noted too that
voting cycles can be catalogued under the mathematical concept of
rotational symmetry. His subsequent suggestion is that cancellation
should hold for _all_ symmetries for _all_ subsets of voters.
What happens when cancellation of ‘rotational symmetry’ is applied to
subsets ? The following is an example by Saari that cancellation isn’t
trivial then. In Table 14 there are 48 voters, and _B_ is selected by
both Borda and Condorcet. In Table 15, 27 voters have been added who
have the mentioned rotational symmetry, with 9 for each subgroup. Now
Borda still selects _B,_ but Condorcet, and the Borda Fixed Point,
select _A._ In Saari’s view, Borda satisfies symmetry, and ‘hence’ is
the better method.
My reasoning is a bit different. First of all, note that I myself have
used an argument similar to that of Saari. In my view, the typical
Condorcet situation of three preferences _A > B > C_, _B > C
> A_ and _C > A > B_ results into indifference rather than an
inconsistency, and I use this against Arrow’s analysis. So I agree with
Saari’s view that such votes cancel. I applaud Saari’s insight that if
you apply cancellation for _all_ cycles in _all subsets_, then the
logic is to get rid of Condorcet’s method and to use Borda’s method.
Table 14: Start with 48 voters: Borda _B,_ Condorcet _B_
_ _
_Candidates and their rank order weight_
_Number of voters_
_A_
_B_
_C_
20
3
2
1
28
2
3
1
_Borda weighted total_
116
124
48
_A versus B_
20
28
_A versus C_
48
0
_B versus C_
48
0
Table 15: Add 27 ‘neutral’ others: Borda _B,_ Condorcet _A_
_ _
_Candidates and their rank order weight_
_Number of voters_
_A_
_B_
_C_
20
3
2
1
28
2
3
1
9
3
2
1
9
1
3
2
9
2
1
3
_Borda weighted total_
170
178
102
_A versus B_
38
37
_A versus C_
57
18
_B versus C_
66
9
Secondly, however, my problem remains that there is the phenomenon of
budget changes. Note that Saari’s example uses a changing electorate
rather than a changing budget. My suggestion is that a change in the
electorate would require a new vote, while we would want to avoid that
in case of a change in the budget. The Borda method would be best,
_only_ when the budget would be really given. When it might change, the
application of cancellation to _all subsets_ becomes doubtful, since
subsets change. There is a fundamental uncertainty with respect to the
future. Consider the following example. At a specific point in time,
the population of a nation is given, and thus the vote for a President
has a specified budget: the population. But, uncertainty sets in again,
when people may withdraw from the race. Only a few actually run. Hence,
we might well want a rule to deal with possible changes in the budget.
Hence, it is not logically required that we cancel votes for all
possible subcycles (also for candidates who are _not_ in the race).
Saari is very strong on the argument that when we accept cancellation
in one case, then we should do so in all cases. I am more sensitive to
the exception: when ‘if one, then all’ does not hold.
Concerning Table 14 and Table 15, my reasoning is - contrary to Saari -
that the added votes cannot be neglected. The argument of rotational
symmetry breaks down when we compare a winner with the alternative
winner - which is a pair - while rotational symmetry requires a third
candidate or more. For the pair, the addition has an effect. When we
consider unrefined winner _B_ and its alternative winner _A_, then the
added votes are in favour of _A_ and no longer ‘neutral’. While _C_ is
important since it shows a cycle for a subgroup of voters, another view
is that _C_ could be neglected since it is not a fixed point. Canditate
_C_ is a typical example of an irrelevant candidate that can cause a
preference reversal in Borda voting. Namely, let us consider Table 15
under Borda voting, and let _C_ decide to drop from the race: then_ A_
becomes the winner. The Borda Fixed Point method has been developed
precisely to deal with that kind of preference reversal.
Thus, when you select your voting method then you must choose between
the properties exemplified by this case. (1) Borda is subject to
preference reversal. In the example of Table 15, when _C_ drops out,
then there would be switch from _B_ to _A_. (2) The Borda Fixed Point
method still depends upon the voting field. In this example, when 27
voters drop out, then there is a switch from _A_ to _B_.
The choice basically is whether we attach more importance either to the
voters or to the candidates. Saari suggests that the candidates are
more important, since he cancels the votes of 27 voters and keeps _C_
in the race. I would say that the voters are important and that
candidate _C_ is less relevant. The proper question would be whether
the winner is a convincing winner. Of course, _C_ can become an
important candidate when we add other voters. But then the argument is
that those voters count, rather than _C_.
Consider the impact of semantics. While it has been a long standing
notion that cycles may also be taken as indifference, so that the votes
cancel, Saari now rephrases this as rotational symmetry, and he
suggests that acceptance of rotational symmetry implies acceptance of
it for all cases and subsets. The label might be a common mathematical
label, but I have a problem with that label in the realm of morality
(and the implied universality). Human beings seem to have biological
preference for symmetry, and by labelling something as ‘symmetry’, it
becomes more attractive. When discussing the different voting schemes,
we should be aware of such effects, and try to focus on what the
properties really mean, and we should make a proper distinction between
a property that is universal and a property that is dependent upon the
situation. Perhaps it might be analysed as the ‘mathematical frame of
mind’ that acceptance of a property for one set also implies acceptance
for all other (sub-) sets, but my conclusion is that when we look
closer, that there is room for more subtlety. Indeed, it might well be
that considerations of symmetry apply to the static situation, but that
we need other considerations for dynamics.
Another example for this need for subtlety is that the ‘rotational
symmetry’ argument breaks down on the _status quo_ (see below).
Saari has also developed an ingenious way to depict voting schemes
geometrically. For 3 candidates, this becomes a triangle, and the
different procedures can be calculated from that. It appears that these
triangles are a good educational tool. However, my experience is that
the computer programs (Colignatus (2001) uses _Mathematica_) are easier
to use, since they take away the need for calculations, while they are
available for more dimensions and also allow for indifference and not
just strict preference. A complex scheme like the Borda Fixed Point
also requires more work with the triangle, while in _Mathematica_ it is
a simple procedure call. It may be noted that above discussion of the
Borda Fixed Point method has been simplified by assuming single
winners. In practice, there can be ties, complicating the search, and
requiring tie-breaking rules.
Pareto
Another consequence of the switch of attention from statics to dynamics
is the recognition of a _status quo_.
There appears to exist another wide-spread confusion about ‘majority
voting’. This idea is that a majority result would still be
democratically valid, even if the winning decision implies a real loss
for the opposition. The counter-example is when the majority decides
that the minority pays $1 to the majority: this is not necessarily a
morally acceptable situation, even though there is a majority. From a
moral point of view, each voting scheme should have two rounds: a first
round to select the Pareto improving points compared to the _status
quo_, and then a second round to select the winner from those Paretian
improvements. The majority rule thus can be regarded as only a
tie-breaking rule, namely for the deadlock when there are more Pareto
improving points. In elections of persons, the status quo can be a
vacancy, and in that respect all candidates could be taken as Paretian.
But the Paretian pre-condition cannot be skipped in general.
The Paretian condition may require some subtlety. Consider the family
choice for a holiday to Greece or Spain, discussed above. If little
Robby considers the holiday to Spain to be a deterioration from the
status quo of not having a holiday at all, then there is moral argument
to say that Spain is not a valid option to take a vote on. However, if
it can be established in a first round that going on a holiday is
unanimously a good idea, then Robby has to accept a possible majority
decision in favour of Spain and against Greece.
One argument against the selection of Pareto improving points is that
people might also cheat about these points. This argument is not
convincing, since Pareto improvement is in one’s own interest. Indeed,
little Robby might try to veto Spain by saying that he does not want a
holiday, and thus he might be trying to bargain to get everybody to
accept Greece. However, this ploy can be prevented by having that first
round on having a holiday, since if he really wants a holiday anyhow,
then he has to show this then. Careful construction of the voting
process thus remains an issue.
A note on cheating
One of the key problems in voting theory is strategic voting behaviour,
better known as cheating. In a scheme like Borda, cardinal utility has
already been reduced to ordinal utility, so perhaps we should be
lenient and allow voters to maximize their utility from the final
outcome by manipulating their vote. But our opinion on this does not
matter, since the ballot generally is secret and we cannot stop people
from voting strategically anyway. In fact, my _Mathematica _programs,
Colignatus (2001), contain routines for cheating. These are simple
routines that assume both full information and that others don’t cheat,
since the mathematics of cheating while assuming that others cheat too
is rather complex, especially when nobody has full information about
the true preferences. Given all this, one surmises that election
results do not reflect the true state.
Thinking about these issues gave me an idea that might be helpful to
elicit the true state. Suppose that each voter is informed in advance
that there is a probability _p _that the ranking order that is
submitted will be used by the election computer for strategic voting.
If the voter submits his or her true ranking, then this is rewarded
with probability _p_ to improve the election result for that voter, and
much better than the voter can, since the computer knows all submitted
rankings. If the voter submits a strategically adapted ranking, then
this is punished with probability _p _namely to improve the election
result for that false ranking. Likely there is a specific value of _p
_that would generate the most truthful election result. Unfortunately,
I haven’t had time to develop this idea.
Conclusion
An election result is ‘as much’ the result of the procedure as of the
preferences. Arrow’s Impossibility Theorem is complex and full with
paradoxes, but the dependence of morality upon time provides a way
towards solution.
There are two key conclusions:
(1) The Pareto condition for the candidates under ballot should not
be neglected - i.e. that only those candidates are voted on that are an
improvement compared to the _status quo_.
(2) The Borda Fixed Point can be seen as a compromise between the
Borda and Condorcet procedures (on Paretian points), and provides a
degree of protection against budget changes.
There is also another conclusion. Voting is complex, and becomes
increasingly complex when the numbers of candidates and voters rise
(especially when we also include indifference and not just strict
preference). Direct election of a President becomes quickly infeasible
for the more advanced voting procedures. From this observation we can
conclude that it is better to have a proportional parlementary system,
so that the elected professionals can use the advanced voting
procedures to select the President. This approach of representation
also prevents that there is a different electoral mandate for President
versus Parliament. Note that the discussion above, on Arrow’s Theorem
and the Borda Fixed Point method, considers single seat elections, and
not multi-seat elections. But the complexity of direct single seat
elections tends to support this conclusion on the overall system of
proportional representation and indirect election of the chief
executives.
36. Some notes on ethics
The following notes on ethics are not well developed but the points are
useful to observe.
(a) I was struck by Keynes’s quote: “along the line of origin at
least, economics - more properly called political economy - is a side
of ethics” (Skidelsky (2000:264)). This is a point that is commonly not
seen by the general public who associate economics with money, and
neither by many economists who don’t appreciate the subject of
political economy.
(b) Ethics focusses on survival and the good life (“flourishing”).
That is, just like laboratory animals require an optimal environment,
humans have their own conditions for flourishing. Csikszentmihalyi
(1997), “Living well. The psychology of everyday life”, clarifies the
required balance between challenge and competence: too much challenge
causes stress while too little challenge causes boredom. The Rasch
model, also known in psychology as the item-response model, or the Elo
model used for Elo rating in chess, seems to fit the situation.
(c) Colignatus (2003), “On the value of life”, essentially focusses
on survival: the lifeyears saved and the allocation over individuals.
On the quality of life, the “flourishing”, I only have a rough outline
“On the price of health”.
(d) The chapter “Without time, no morality” of course links with the
discussion in chapter 19 on determinism and free will, and the general
importance of ‘dynamics’ for this book.
(e) There was a seminar by McCloskey on virtue ethics that was
illuminating and that I can advise to who has a chance to attend. Smith
(1759, 1984), “The theory of moral sentiments”, featured strongly.
(f) A general point in ethical theory is that people aren’t really
‘souvereign consumers’. They grow from dependent children to mature
adults to dependent seniors, so that there is always a degree of
dependency. Political economy takes this into account. The standard
economic approach that assumes souvereign consumers however can still
be useful for analysis even while being limited in this respect.
(g) Another point concerns the distinction between ‘rules’ and
‘rhetorics’. In ethics, it does not suffice to have rules only, since
these must be applied to practical situations – where rhetorics apply.
In law, there are not only laws but also courts. Current literature in
economics tends to emphasize rules. If economics had courts too then
there might be less imbalance. The suggestion that there be economic
courts links with the idea of an Economic Supreme Court.
(h) There are some other advisable books that enrich our
understanding of humanity, (social) behaviour, ethics and its
biological roots, which form the input for and target of political
economy. Tiger (1992), “The pursuit of pleasure”, mollifies the
economistic calculus of utility, which at the same time clarifies that
it still can be useful to use small abstract (simplistic) models to
develop arguments that can improve the lifes of many. Damasio (2003),
“Looking for Spinoza”, delves into the brain to understand human
emotion and feeling. Though many dimensions exist, there still is the
pain and pleasure dichotomy that links to ethics. Damasio also notes
that biological ‘emotions’ (generally) arise split-seconds before being
reflected in ‘feeling’ in the mind. This phenomenon raises the question
of ‘free will’ and the reader is referred to that section in chapter 19
above. De Waal (2001), “Tree of origin”, discusses whether primate
behavior can tell us something about human social behaviour, and the
same themes arise. Cavalli-Sforza (2000), “Genes, peoples and
languages”, focusses on recent human evolution. Diamond (1997), “Guns,
germs, and steel”, makes us aware of the impact of mere geography. All
these books clarify that political economy can be of value for humanity
by keeping an open eye for the study of humanity itself.
(i) Cavalli-Sforza (2000:207) concludes with this statement: “It
will be necessary, for example, to be more successful in spreading the
necessary moral values to the whole world. Is the amount of deception,
hatred, exploitation, and unrestrained selfishness we observe in almost
every society inevitable ? We need not be too pessimistic and should
admit that people do not always display their worst qualities. But it
would be valuable to learn exactly the conditions that elicit these
destructive tendencies, in order to systematically prevent them.
Overpopulation and extreme competition for valuable resources
undoubtedly contribute. Our aptitute for social engineering is limited,
although we must become more serious about work in this area, so as to
end - or at least reduce - major social ills such as poverty,
ignorance, population growth, racism, drug addiction, crime, and other
social epidemic and endemic diseases that afflict us. Our efforts in
this regard can be helped by studying cultural transmission and the
forces of conservatism that hinder useful innovations, as well as the
danger posed by promoting and accepting great changes too soon.” I can
only agree with this, and the current book fits this objective.
Book VIII Supportive notions
37. On the nature and significance of a free lunch
It has been a cause of wonder for the present author why other
economists are not more outspoken on the Tax Void, and why above
theorem on the possibility of returning to full employment meets such
disbelief as it apparently does. In the course of time, I found that
the following issue forms part of the explanation.
Many economists think that there are no free lunches. It may even be a
dogma or mantra to them. With this general attitude, they close their
eyes to the free lunch that presently exists in the inefficient labour
market. They adhere to their ‘no free lunch’ philosophy regardless of
what arguments other people forward. My diagnosis is that this is one
of the reasons why the debate on unemployment is rather stuck.
It actually can be shown that the economy is full of free lunches. We
will discuss two examples below, namely the examples of the consumers
surplus and economic growth. By regarding these examples we will better
appreciate the _nature and significance_ (as Robbins might say) of a
free lunch. When the possibility of a free lunch is accepted, then we
can discuss unemployment in more realistic terms.
Some quotes
The American science fiction writer Robert Heinlein once created a
rough Moon Colony where the rules of the free market are exploited to
their limits. In this colony the phrase “Your money or your life” is
not a criminal threat but a sound business proposal - and a bargain for
many as well. In the same vein all incidents in the novel are subject
to bets - and after some consideration, the reader of this novel may
well accept this as a useful system of rational contingent forward
markets. Then, properly, the slogan & law of this Moon Colony is
TANSTAAFL: “There Aint No Such Thing As A Free Lunch”.
TANSTAAFL is rather “accepted wisdom” in the economics profession, and
not something that is subject to critical discussion. There are only
few explicit statements on the supposed absence of a free lunch. A
recent statement is by Cnossen & Van Ewijk (1995):
“No society limited in resources can for a moment proceed from the
premise [sic] that there is such a thing as a free lunch. Dispassionate
analysis of the problem and hard-headed calculation of the costs of
alternative courses of action are called for. This applies especially
to the economics discipline, which gives center stage to the concept of
opportunity costs.”
So, evidently, in the views of these authors, people disagreeing to
their views on this issue are emotional or soft-headed !
Coase (1994:200) has a fine anecdote:
“Charles Walgreen in 1936 withdrew his niece from the University of
Chicago because he had been informed that the university taught free
love and communism. I know nothing about the university’s teaching on
communism but presumably Mr. Walgreen would not have been mollified to
learn that the true Chicago view is that there is no such thing as a
free love. Eventually, however, Mr. Walgreen was convinced that he had
been misinformed (...)”
The British newspaper The Economist (1994b) and the Dutch economist Van
Bergeijk (1994) state, in reaction to proposals by Snower, that there
would be no free lunch on the labour market. Even with current
unemployment, it would not be possible to change taxes, contributions
and benefits in such manner that this would raise employment
opportunities for the unemployed without other agents having to pay
some bill.
These latter authors use arguments for their views. So their judgement
does not seem dogmatic. However, their arguments have been refuted.
Authors like Snower and myself, and many others, have also pointed to
the possibilities for improvement in the labour market, and these
arguments have not met with convincing rejections. So it may well be
that TANSTAAFL works its ways in the back of the minds and hinders
proper balancing of arguments.
We somehow might welcome the Cnossen & Van Ewijk statement, since it
makes explicit what often is only implicit. In the following I shall
deal with the problem in general. I hope to banish TANSTAAFL to the
domain of science fiction, so that thereafter we can discuss the labour
market in more useful terms.
Consumers surplus
The more innocent examples of free lunches happen around us every day.
For example, in a free country, a transaction occurs only when both
parties get something out of it. TANSTAAFL adepts will hold that when
there is a transaction, and people pay for their lunch, then there
clearly is no free lunch. However, the theory of the consumers surplus
reminds us that you may pay for your lunch, but likely not as much as
you might be willing to pay. If you would not get more out of it, there
would be little point is actually doing the transaction. In everyday
life, we see few people exchanging dollars for dollars, just for the
fun of it. So if _p _is what you pay for your lunch, and if _wtp _is
your willingness to pay, then _wtp - p _is your free lunch.
One might argue that the TANSTAAFL conjecture properly reads that _p
_0. Thus TANSTAAFL-ists accept that _wtp > p, _but the point would be
that you have to invest a nonzero amount before you can reap greater
benefits. It would seem to me that the following is the proper reaction
to this:
1. We might accept a definition that ‘no free lunch’ means _p
_0.
2. However, that definition does not warrant universal truth.
Some goods have _p _= 0, notably endowments, ideas and, in a sense,
public goods.
3. So, please then, do not use this mal-definition to kill
arguments on the labour market that concern new ideas.
4. And, please see the point that it may be advisable to define
‘_p _0’ ‘there are some costs’, and ‘_wtp > p’ _‘there_ _is a free
lunch’_._
In a sense, the discussion might only be about words. But there are
also emotional connotations involved, that should cause us to be rather
careful in that choice.
Economic growth
Economic growth is another instance of manna from heaven, and also a
phenomenon that has been with us since the dawn of mankind.
An invention in one industry will generally have consequences for the
entire economy. The industry of origin can seldom claim all proceeds.
When the optimal ratio of production factors changes, then prices
change. E.g. just by mentioning the possibility of other prices, one
signals to the other parties that there is room for discussion. The
other parties will use that room, and their knowledge and possessions,
to claim part of the economic value of any innovation. Other parties
have had no effort in bringing about the innovation, but they consider
themselves partners in the industry, they know their leverage, and,
thus, exploit it. Their advantage not only concerns the consequences of
a better product, but also an improvement of their income position.
Model
In a general equilibrium framework we consider an economy with 400
units of labour and 600 units of capital. The economy produces food and
clothing, and a social welfare function (SWF) determines the optimal
combination. Here, our SWF will be a Cobb-Douglas function that
neglects the distribution of income:
(SWF)
Labour _a _en capital _k _are allocated to the food (v) and clothing
(k) industries via _av + ak = 400 _and _kv + kk = 600. _Industrial
output is determined by the production functions. Here we take
CES-functions, that have a constant elasticity of substitution between
capital and labour:
Equilibrium and the optimum are found at 278 units of food and 253
units of clothing, with a distribution of the factors of production of
_av/ak_ = 299/101 and _kv/kk_ = 210/390.
The allocation can be shown using two figures. Figure 36 confronts the
social welfare function with the Production Possibility Curve (PPC).
Figure 36: Social Welfare and the Production Possibility Curve
The PPC gives those combinations of food and clothing that can be
produced with the scarce resources. The choice of the highest possible
value of the SWF generates a tangent of a contour of the SWF with the
PPC. The tangent gives the optimal price ratio (thus trading ratio) of
food and clothing.
Figure 37 confronts the production functions of the separate industries
in an Edgeworth-Bowley diagram. The food industry has its origin in the
lower left-hand corner, and the clothing industry has its origin in the
top right-hand corner. The amounts of capital and labour that are not
allocated to the food industry are allocated to the clothing industry.
The drawn contour for the food industry gives those combinations of
capital and labour that produce the same amount of food. That contour
is touched in a tangent by a contour of the clothing industry. The
collection of all tangency points is called the contract curve. The
tangent drawn here passes through the optimum selected by the SWF. This
tangent thus also determines the price ratio of wages and capital rent.
Now we assume that there is an innovation in the clothing industry.
This innovation can be of technical or organisational origin, and it
causes that the same garment can be produced with a little less labour
but a little more capital. To be concrete: the production possibility
is discovered that can be stated in the production function _clothing =
CES_[0.2, 0.5]_._ Is this innovation useful ? The answer appears to be
that labour is the factor that is relatively scarce and that this
innovation allows its better use, so that welfare can rise to 282 units
of food and 269 units of clothing. The allocation of factors of
production becomes _av/ak_ = 309/91 and _kv/kk_ = 202/398.
Figure 37: Edgeworth-Bowley diagram for the factors of production
Figure 38 and Figure 39 present the same plots as before so that one
may see how the economy changes. The figures speak for themselves. It
will be clear that our analysis is comparative statics. How quickly the
prices change, and how quickly the agents react, will be a question of
dynamics.
Figure 38: SWF and PPC of two situations
Figure 39: Edgeworth-Bowley of two situations
The free lunch
Above model was not perfect but helps us to understand how a free lunch
percolates through the economy. It helps us to understand what a free
lunch actually is.
In above model, the innovation falls from heaven like manna. The
innovation is the free lunch. One may see the tautology: If you accept
the model, then there is a free lunch; and you accept the model if you
see innovation as a free lunch.
One may hold that above model is incomplete. One would want to
introduce a separate R&D sector, and then there will be a balancing of
R&D costs and the expected increase in national income. As an
economist, I’m very much in favour of developing such models. However,
actually doing this only moves the question one station further, and
does not answer the proper question. For, it is possible that an
economy spends 99% of its resources to R&D, and still does not come up
with innovations. Good ideas remain like manna from heaven.
You may hold the view that agents already expect economic growth, so
that they will not regard it as a free lunch. This reminds of the
attitude of some children of rich parents who expect a rich inheritance
and who don’t show gratitude for their daily bread. The point to note,
though, is that the concept of a free lunch is not an expectational
variable, but one of circumstance. There is a free lunch or not,
whatever one expects. Indeed, as another example, our wealth is a
cumulation of free lunches in the past. That we don’t experience this
as a free lunch anymore, is more a sign that we are spoiled, rather
than a sign of our dynastic rationality.
And even if we would design a revised expectational concept of a free
lunch: then perfect foresight or rational expectations are only
assumptions. There is always the possibility of a surprise idea. The
future is uncertain (though predictable) - even though our scientific
predisposition is deterministic.
Let me rephrase the point that I want to make here. There are data
(exogenes or endowments such as soil, sun, technical relations and the
like), the economy depends on the use of these, and the development of
the economy can be described in terms of the developments in these
data. The data are for free. Ideas are part of these data, and the
(major) source of uncertainty. In this terminology, there are free
lunches_ by definition_. That is the crux. When economists better deal
with their definitions, we get better economics.
Conclusion
Our discussion on the consumers surplus showed that much may be a
matter of words. However, using an abstract argument and a concrete
small general equilibrium model, we showed that innovation and economic
growth are an example of a free lunch for the whole economy. Our
intention was to refute the attitude of “there aint no such thing as a
free lunch”. Hopefully, this refutation creates more room for
discussion of proposals concerning the present immense inefficiency on
the labour market. The latter discussion is especially important, since
the major proposals for solving the inefficiency concern _ideas_ by
impartial economists.
Note 1999: I was afraid that I would clash with Paul Krugman on this
issue, since he has a Fortune column ‘No Free Lunch’. To my great
relief, Krugman (1999:167) however writes: “And this brings us to the
deepest sense in which depression economics has returned. The
quitessential economic sentence is supposed to be “There is no free
lunch.”; it says that there are limited resources, that to have more of
one thing you must accept less of another, that there is no gain
without pain. Depression economics, however, is the study of situations
where there _is_ a free lunch, if we can only figure out how to get our
hands on it, because there are unemployed resources that could be put
to work. In 1930 John Maynard Keynes wrote that “we have involved
ourselves in a colossal muddle, having blundered in the control of a
delicate machine, the working of which we do not understand.” The true
scarcity in his world - and ours - was therefor not of resources, or
even of virtue, but of understanding.” Hurray!
38. Proper definitions for uncertainty and risk
This discussion will present proper definitions for uncertainty and
risk. Such definitions are required since the current definitions in
common use are rather erroneous and generate conceptual problems.
Uncertainty
The new definitions are - see also Figure 40:
(1) First there is the distinction between _certainty_ and
_uncertainty_.
(2) Uncertainty forks into _known categories_ and _unknown categories_.
(3) Known categories forks into _known_ and _unknown probabilities_.
(4) Unknown probabilities forks into_ assuming a uniform
distribution_ (Laplace) or use_ _non-probabilistic _techniques like
minimax _or _neglect._
Note that these definitions only use certainty, knowledge and the
distinction about categories (category-uncertainty), and that they do
not use the term ‘risk’. Thus an independent definition of ‘risk’ is
possible.
A.S. Hornby (1985) “Oxford Advanced Learner’s Dictionary of Current
English” defines ‘uncertain’ as: “1 changeable; not reliable: _~
weather; a man with an ~ temper_. 2 not certainly knowing or known:
_be/feel ~ (about) what to do next; a woman of ~ age_, one whose age
cannot be guessed”. The above fits this.
Figure 40: A diagram of the new definitions
Risk
Hornby (1985) defines ‘risk’ as: “(instance of) possibility or chance
of meeting danger, suffering loss, injury, etc.” Also: “at the ~ risk
of / at ~ of, with the possibility of (loss etc.)”.
Thus, if there are possible outcomes _O_ = {_o1, o2, ..., on_}, then
the situation is risky if at least one of the _o_’s represents a loss.
The risks are the _oi_ that are losses, thus _Risks_[_O_] = {_oi_ _O
| oi_ is a loss}. The risk factors are the positions or index numbers
of the risky outcomes, the i’s, or the dimensions (the causes that make
such positions to be filled).
We will use the term ‘valued risk’ when a risk is valued with money or
utility. When all risks have been made comparable by valuing them, then
we can add them, and we will use the term _expected risk value_ for the
_expected value of the ‘valued risks’_. Then, crucially, once these
definitions are well understood, then we may also use_ ‘the risk’_ for
the expected risk value. [110]
With such understanding, risk will be _r _ = -E_x_<0[_x_] [111] or for
short _r_ = -E[_x_ < 0]. [112]
Valued risk deals with the cases when probabilities are known _or_ when
unknowns are assumed to be uniformly distributed over known categories.
It is not customary to use the term ‘risk’ for unknown categories. For
example, it is uncommon to say, or write economics papers about this,
that “all our lives are _at risk_ of a suddenly imploding universe, or
black hole hitting Earth, or waking up as a cockroaches”. Such real
‘Acts of God’ are commonly neglected. Note though that it still remains
possible to say that a situation is risky even though one cannot put a
number to it. Above expectation may be indeterminate since one may lack
knowledge about the probability distribution or even the categories.
_ _
_Relative_ risk is defined as _r(t)_ = _t_ - E[_x < t_] for some target
level _t_. Risk (or _absolute_ risk) takes _t_ = 0, and relative risk
would allow for a different target level. [113]
An interesting application is when _x_ is a stochastic rate of return
and _r _the certain rate, so that there is relative risk _r(r)_ _=_ _r_
- E[_x < r_]. This relative risk answers the question: What is the
probable loss with respect to a target return of _r _? Here, _r_ -
_r(r) = _E[_x < r_] gives the weight of underperformance in the total
target return (which weight has to be compensated by probable profits
to achieve the target).
_ _
_Conditional _(relative) risk is defined as _k(t)_ = _t_ - E[_x_
| _x < t_] for some target level _t_. With respect to rates of
return, conditional risk _k(r)_ answers the question: What would one
expect to lose with respect to _r_, if earnings actually underperform
and fall below _r_. Indeed, _r_ - _k(r)_ would give your expected
return when actually underperforming.
Conditional risk is related to relative risk by the property that E[_x_
| _x < t_] = E[_x < t_] / Pr[_x < t_]. The probable loss thus is
corrected for the probability of the loss. Or, the probability measure
in the expectation is corrected so that a density is taken that sums to
1. [114]
Example
In everyday parlance, profit and loss are nonnegative concepts. For
example, if the difference between revenue and costs is $-10, then your
loss is $10. It is only in mathematical economics that profits are
defined as a general profit function such that ‘negative profits’ are
possible. To understand risk, we however return to the everyday
parlance convention.
Let us have a prospect that can give _profit_ with probability _p_, and
_loss_ with probability 1 - _p_. We denote this as Prospect[_profit,
-loss, p_]. We call _profit * p_ ‘probable profit’ and _loss * (1 - p)_
‘probable loss’. Then the following definitions apply:
· Expected Value = _ _= _p profit + (1 - p) (-loss)_ = probable profit
- probable loss
· Risk = risk value = expected value of the risks = probable loss = _(1
- p) loss_
· Risk Ratio = Risk / (ExpectedValue + Risk) = _(1 - p) loss / (p
profit)_
· Thus: Expected Value = _p profit _(1 - Risk Ratio)
· Risk Probability = cumulative probability of all losses (in this case
1-_p_)
Risk is the (absolute value of the) down side of a bet. A venture is
judged to be risky if the probable loss is large. Note that this notion
still is somewhat vague. A probable loss can be large because of the
probability or because of the sum of money involved. This vagueness is
unfortunate, in some respects, but here is little to be done about it,
since this vagueness is inherent in working with probabilities. In
fact, this vagueness is an essentially positive aspect of working with
probabilities. For, when we have different prospects, then we can order
and evaluate them on risk, neglecting differences in losses and
probabilities.
Colignatus (1999, 1999a) further develops these notions for simple
binary prospects, multidimensional prospects, joint prospects, and
continuous probability densities. An interesting application is the
‘Markowitz efficiency frontier’, but now with risk rather than the
spread.
Wrong use in economics 1921-2005
The above definitions are proper in the sense that they conform to
every day parlance and the definitions provided by Hornby’s dictionary
op. cit.. The definitions provided here however differ from the use
within the economics literature. First there are the definitions of
Knight (1921) that have been adopted widely in economics, as for
example in The New Palgrave (1998:III:358). Or it has become custom in
finance to associate risk with the standard deviation. And some
mathematical statisticians use another concept of risk. Let us discuss
these in turn.
Uncertainty and risk
The New Palgrave, Eatwell c.s. (1998:III:358), gives the current common
view:
“The most fundamental distinction in this branch of economic theory,
due tot Knight (1921), is that of risk versus uncertainty. A situation
is said to involve _risk_ if the randomness facing an economic agent
can be expressed in terms of specific numerical probabilities (these
probabilities may either be objectively specified as with lottery
tickets, or else reflect the individual’s own subjective beliefs). On
the other hand, situations where the agent cannot (or does not) assign
actual probabilities to the alternative possible occurences are said to
involve _uncertainty_.”
Indeed, most economic texts use this distinction in this manner (at
least, up to now). However, I cannot disagree more. The objections to
Knight’s concept are:
(a) Certainty and uncertainty are _binary_. So, if a situation is
not uncertain, then we have certainty, and there is no assigning of
probabilities.
(b) If I am uncertain about a situation and assign equal
probabilities to all cases - the Laplace suggestion - then according to
Knight this no longer is uncertainty!
(c) In Hornby’s definition, the distinction is not between known and
unknown probabilities, but the distinction is between _events_ and
_human thought_.
Figure 41 contains a diagram of the objectionable use of terms
1921-2005.
Figure 41: A diagram of the current but objectionable use of terms
The diagram clarifies the inconsistency with the binary character of
certainty/uncertainty, the curious treatment of “Laplace”, and the
over-use of terms by introducing the term ‘risk’ where there already is
the qualification that the probabilities are known.
Risk is not the variance
The finance literature often uses the term ‘risk’ for the variance or
spread (standard deviation) of the distribution of the rates of return
of investments. This would be an improper use of the term. Suppose that
one has a very profitable venture without the possibility of a loss.
Suppose that the rate of return of this venture has a large variance,
from mildly profitable to highly profitable. Is this a risky venture ?
No, not in the usual understanding of the term.
Risk is not the negative of expected revenue
In mathematical statistics, some authors, like Ferguson (1967), define
‘risk’ as ‘expected loss’. However, it appears that they actually
regard ‘loss’ as the negative of total returns (i.e. - revenue), so the
definition used is -(_p profit + (1-p) (-loss))_, which is the negated
expected value. This use of the term ‘risk’ is inappropriate. My
proposal is to use the word “due” to stand for the negative of expected
value, so that the standard statistical decision theory (with the game
against nature) can be described as minimising _due_.
Note on Bernstein’s “Against the gods”
I came across Bernstein (1996) “Against the gods”, and found it equally
entertaining as his “Capital Ideas”. One comment is that Bernstein
indeed emphasises Knight’s and Keynes’s statements on “uncertainty”. My
answer to that is, again, that unknown probabilities or even unknown
categories indeed are serious cases of uncertainty, so that earlier
writers on the subject were right in emphasising that seriousness.
However, we should not be tempted to reserve the word “uncertainty” to
only those cases. So with all due respect to Knight and Keynes, the
definitions provided here are the proper ones.
Note on Wilson & Crouch (2001)
Wilson & Crouch (2001), “Risk-benefit analysis”, adopt the same
definition of “risk” as discussed here. I saw this only after the first
edition of this book. Since professor Wilson has been teaching on the
subject for decades and his book only collects his teaching material I
apparently only rediscovered what was already clear to him. Perhaps my
presentation is a bit clearer since I use the formal E[.] notation.
This chapter remains useful since it clarifies the confusions from the
other definitions. Where risk is the product of probability and
severity, this book also benefits from the emphasis on this definition,
since, where I started to develop this argument after the Fall of the
Berlin Wall in 1989, we have to deal with a future where there are huge
dangers: though with only a small probability but on balance a relevant
risk.
Book IX
Reduced form
39. The possibility of full employment in the welfare state
Introduction
Above we noted that the structural form of western welfare states is
quite complicated. We would like to have a more enduring result than
awareness of complexity, and therefor we adopt the Definition & Reality
methodology. As said, a_ proposition - _as a statement on reality - can
be regarded as a mathematical theorem about/within a model of stylized
facts. When there is a tautology, we attain truth by definition. So we
now (a) restate what we consider to be the stylized facts, (b) define
our concepts, (c) develop theorems and proofs, (d) link back to
conclusions about reality.
The reduced form that is most relevant concerns the (long run)
comparative statics of the regimes of full employment (1950-1970;
Japan/Sweden) and unemployment (1970-2005).
This kind of comparative statics should not induce us to think that we
abolish dynamics, though. Stagflation has both a dynamic (inflation)
and a static or stationary (unemployment) aspect. When we skip proper
dynamics and discuss regime switches in which unemployment features as
an important switch variable, then Phillipscurve processes are included
in the switching process, even though they don’t feature explicitly in
the reduced form.
To attain the necessary level of generality, we use a reduced form
where the economy is mapped into a model with three types of agents.
One type is the net receiver; and two types are net tax payers. Since
the latter two points give a line, that single line represents the
state of the economy. The regime switch depends upon the choice of tax
parameters.
Stylized facts
There are regimes of full employment (1950-1970; Japan/Sweden) and
unemployment (1970-2005).
In the welfare state, it is more efficient to have full employment.
Unemployment causes lower income - not only directly as in
old-fashioned capitalism but also, more noteworthy, by the additional
benefit burden. Unemployment can have an adverse effect on inflation
when it causes a shift of the Phillipscurve.
It turns out that the propositions that are most interesting, from the
viewpoint of political economy, do not require continuity, and can be
formulated by assuming dichotomous High and Low productivity labour,
combined with one class of Benefit recipients. This assumption allows
for a reduced form formulation that allows for generality. For
expository reasons we can take social subsistence and productivities as
purely constant. In the simple mathematical model the dichotomy gives
fixed numbers, in actual observation they are subgroup averages which
depend upon general equilibrium processes. The benefit level is rather
not an average but a threshold, like the surface of the sea at
Scheveningen beach. The words _Benefit_, _High_, and _Low_ give letters
BHL, and this abbreviation may be pronounced - converged upon after
many walks - as ‘beachly’.
It is a stylized fact that welfare states are BHL. Checking this
requires next definitions.
Concepts
Here we will redefine variables such as _H, Z, b, n etcetera. _Also the
reduced tax function will be _T_(.) as opposed to structural _T_[.].
These redefinitions hold for this chapter 39 and chapter 40 - that
together form a reduced form unity.
Definition: Biological subsistence, for survival, is _S._
Definition: An economy is a welfare state iff people without
income are not left to charity, stealing or death, but get a benefit
_B._ The benefit _B_ has the following properties:
i. the net benefit has the social subsistence level _B S_,
ii. people on benefit may not work, [115]
iii. eligible are:
iii-a. permanent benefit recipients (e.g. ‘the elderly’)
iii-b. people able to work but currently unable to earn at least
net_ B _(these people are called ‘the unemployed’).
Remark: it is useful to have category (iii-a) in the model. It
introduces a degree of sufficient complexity. When there are levies
even under full employment, then it is easier to understand that wrong
co-ordination may cause a switch to unemployment. But (iii-a) might
count zero people.
Remark: Property (iii-b) has the effect of a legal minimum wage. It
sets a floor in the market. We might introduce a benefit threshold (for
workers) _XB_ such that _S XB < B,_ but for expository reasons, we
take _XB = B._
Remark: The reservation wage effect is as follows. When vacancies with
net income higher than _B_ are registered, then the relevant
unemployment benefits are simply scratched. This mimics the array of
measures needed for continuous reality.
Remark: This definition implies that people working with subsidies in
the Swedish/Japanese case are not on ‘benefit’. Such subsidies thus
must be accounted differently, basically as part of taxes.
Remark: The black economy (another form of working while on welfare) is
neglected. We neglect also the case that some people hate being on
welfare, and thus continue working even when their net earnings are
below the benefit threshold (_S < net earnings < XB _).
Definition: A welfare state is _bhl_ iff it remains meaningful to
trisect its membership into the economic classes of Low and High
productivity workers and permanent Benefit recipients.
Definition: A welfare state is nonrevolutionary, iff its economic
classes and their data are stable across the change of employment
regime.