#Biostatistics 410

#CHI-SQUARE TEST FOR GOODNESS OF FIT
#ZAR EXAMPLE 22.1
ZAR=read.table("ZarEX22.1R.txt")
ZAR
attach(ZAR)

chisq.test(observed,p=expected,rescale.p=TRUE)

#WITH YATES CORRECTION:

chisq.test(observed,p=expected,rescale.p=TRUE, correct=TRUE)
#NOTE THAT THIS APPARENTLY DOESN'T WORK IN R FOR NON 2x2 TABLES
#SO CALCULATING BY HAND:

O=observed
E=expected
df=1
YatesCHISQ=sum(((abs(O-E)-0.5)^2)/E)
YatesCHISQ

YatesProb=1-pchisq(YatesCHISQ,df)
YatesProb