data=read.table("clipboard",header=T)
data[1:5,]
data
data[1:5,]
hw1=data[,1]
hw2=data[,2]
hw3=data[,3]
mean(hw1==0)
mean(hw2==0)
mean(hw3==0)
hw1=hw1[hw1>0]
hw1
length(hw1)
hw2=hw2[hw2>0]
hw3=hw3[hw3>0]
length(hw2)
length(hw3)
summary(hw1)
mean(hw1<=94)
mean(hw1>94)
mean(hw1>=94)
mean(hw1<=99)
mean(hw1>=99)
mean(hw1<=83.5)
mean(hw1>=83.5)
mean(hw1<99)
summary(hw1)
summary(hw2)
summary(hw3)
summary(data)
mean(hw1<=60)
sd(hw1)
sd(hw2)
sd(hw3)
hist(hw1)
hist(hw1,freq=F)
lines(density(hw1))
?hist
hist(hw1)$counts
hist(hw1,breaks=seq(50,100,by=5))
hist(hw1)$counts
hist(hw1,breaks=seq(50,100,by=5))$counts
par(mfrow=c(2,2))
hist(hw1,freq=F)
lines(density(hw1))
hist(hw2,freq=F)
lines(density(hw2))
hist(hw3,freq=F)
lines(density(hw3))