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Re: Electoral college probablities
Posted:
Oct 31, 2000 3:59 PM


In article <G38p38.439@cwi.nl> "Peter L. Montgomery" <PeterLawrence.Montgomery@cwi.nl> writes:
> In the US presidential election, the winner is determined >by electoral vote rather than by popular vote. >What is the chance that the two will give different outcomes >in an otherwise close race? >
Okay, I made the following assumptions:
There are 3 states, each with 2n+1 voters. Each voter is equally likely to vote for either candidate, and each voter's choice is independent of the others'.
Write f(n) for the probability that the electoral and popular vote winners are different.
I computed f(n) for n between 1 and 50. It looks like f(n) is very well approximated by a function of the form
A + B log(n) + C log(n)/n
for suitable constants A, B and C.
f(50) is about .16, and f'(50) is about .000033 .
Steven E. Landsburg steven@landsburg.com 



