[EM] Bias-Free in the historical census apportionments
Michael Ossipoff
mikeo2106 at msn.com
Sun Jan 21 09:19:45 PST 2007
In the recently-posted historical census apportionments, BF did worse than
Webster in every census apportionment where those 2 methods apportioned
differently.
Dan, did you definitely do the Bias-Free that I defined in the posting just
before this one?
If so, then the only possible explanation is that the free seats required by
the seats-for-every-state rule caused so much small-bias that Webster's
slight large-bias is needed to cancel it out, resulting in less measured
bias with Webster.
Bias-Free is genuinely bias-free if the frequency distribution is flat. With
a flat distribution, Webster is sliglhtly large-biased. Add a slight
large-bias due to the distribution, and both methods' apportionments are
large-biased, but Webster moreso, because Webster has some large-bias of its
own.
So it must be that the free-seat small-bias is making Webster the best one,
because it comes closest to exactly canceling out the free-seat small-bias.
Of course Bias-Free and Weighted Bias-Free could have their rounding points
carefully moved upward in order to very nearly cancel out the free-seat
small-bias.
The best solution is to make sure that the House is large enough that all
the states _qualify_ for at least one seat, in every census. That could be
done separately, or a method could carry it out as part of the method's
rules.
In any case, since that's how the House should be, I claim that it's
important to also report correlations based on not having a free-seat rule.
Mike Ossipoff
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