Similarly the estimate of b' is

=S=(X_{i} - [=X])(Y_{i} - [=Y])

[^b]' = -------------------------------

=S=(X_{i} - [=X])^{2}

and of a' is

â' = [=Y] - [^b]'[=X]

where X_i = ln F for each known group and Y_i = P for each known group.

These calculations are shown in table 4.