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Bill Clinton Poll Results

The May, 1992 Wall Street Journal presidential poll of 750 voters put Bush at 36%, (270 voters) Perot at 30% (225) and Clinton at 28% (210). The estimate for Bush's margin over the #2 man is six percentage points. Establish a confidence interval for this estimate. See "Bush" for an explanation of the general procedure.

URN 36#1 30#2 28#3 a

1= Bush, 2= Perot, 3= Clinton

REPEAT 1000
SAMPLE 750 a b


Take a sample of 751

COUNT b =1 bu


Count the Bush voters, Perot voters, etc.

COUNT b =2 pe
COUNT b =3 cl
CONCAT pe cl seconds


Join the Perot/Clinton results

MAX seconds c


Find the #2 guy's result

SUBTRACT bu c d


Find Bush's margin over #2

DIVIDE d 750 e
SCORE e z
END
HISTOGRAM z
COUNT z <=0 m
DIVIDE m 1000 mm
PERCENTILE z (2.5 97.5) k


Find the 2.5th and 97.5th percentile of the resampled results.

PRINT mm