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CHAPTER17

SOLUTIONSTOPROBLEMS

17.1(i)Letmdenotethenumber(notthepercent)correctlypredictedwheny=0(sothe

0i

predictionisalsozero)andletmbethenumbercorrectlypredictedwheny=1.Thenthe

1i

proportioncorrectlypredictedis(m+m)/n,wherenisthesamplesize.Bysimplealgebra,we

01

canwritethisas(n/n)(m/n)+(n/n)(m/n)=(1−y)(m/n)+y(m/n),wherewehaveused

0001110011

thefactthaty=n/n(theproportionofthesamplewithy=1)and1−y=n/n(theproportion

1i0

ofthesamplewithy=0).Butm/nistheproportioncorrectlypredictedwheny=0,andm/n

i00i11

istheproportioncorrectlypredictedwhenyi=1.Therefore,wehave

(m+m)/n=(1−y)(m/n)+y(m/n).

010011

Ifwemultiplythroughby100weobtain

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