# Chapter 7 R examples

toluene = c(543,523,431,635,564,549)
control = c(535,385,502,412,387)
qqnorm(toluene)
shapiro.test(toluene)
qqnorm(control)
shapiro.test(control)

t.test(toluene, control)



control = c(10.0,13.2,19.8,19.3,21.2,13.9,20.3,9.6)
ancy = c(13.2,19.5,11.0,5.8,12.8,7.1,7.7)
qqnorm(control)
shapiro.test(control)
qqnorm(ancy)
shapiro.test(ancy) 

t.test(control, ancy) 

# One-sided t-test:

control = c(10.0,13.2,19.8,19.3,21.2,13.9,20.3,9.6)
ancy = c(13.2,19.5,11.0,5.8,12.8,7.1,7.7)
t.test(control, ancy, alternative="greater") 


# Power calculation:

power.t.test(delta=1.8, sd=4.0, power=0.80, sig.level=0.05, type="two.sample", alternative="two.sided")

# Mann-Whitney-Wilcoxon test:

growth = c(17, 20, 170, 325, 22, 180, 60)
gap = c(22, 29, 13, 16, 15, 18, 14, 6)
qqnorm(growth) 
shapiro.test(growth)
qqnorm(gap)
shapiro.test(gap)

wilcox.test(growth,gap, alternative="two.sided") 


control = c(10.0,13.2,19.8,19.3,21.2,13.9,20.3,9.6)
ancy =c(13.2,19.5,11.0,5.8,12.8,7.1,7.7)
wilcox.test(control,ancy, alternative="greater")