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# Chisq test of goodness of fit: 
# Legalization, Decriminalization, Existing Law, No Opinion
# Proportion in population known.
# Data collected after airing of advertisement.
# Hypothesis: Does the ad change the distribution of opinion?
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x<-c(39,99,336,26)
chisq.test(x,p=c(0.07,0.18,0.65,0.1))
qchisq(.99,3)
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#Chisq test of independence using HairEyeColor data
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data("HairEyeColor")
HairEyeColor
chisq.test(HairEyeColor[,,"Female"]) #Independence of hair color and eye color for females
dim(HairEyeColor[,,"Female"])
chisq.test(HairEyeColor[,,"Male"])
chisq.test(HairEyeColor[,,"Male"]+HairEyeColor[,,"Female"]) #Both genders together
margin.table(HairEyeColor,c(1,3))
chisq.test(margin.table(HairEyeColor,c(1,3))) #Independence of hair color and gender
chisq.test(margin.table(HairEyeColor,c(2,3))) #Independence of eye color and gender