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> x <- 1:200
> hist(x,freq=F)
> x <- rnorm(n=1000,mean=2,sd=1)
> hist(x,freq=F)
> lines(density(x),col="blue",lwd=3)
> x <- 0:6
> lines(x,dnorm(x,mean(x),sd(x)),col="red",lwd=3)> x <- rnorm(n=1000,mean=2,sd=1)
> sample(x=x,size=100,replace=FALSE)

 

 一个简单的抽样循环：

> sample_means <- c()
> for (i in 1:100){}
> for (i in 1:100){
+ sample <- rnorm (size,mean=mean,sd=sd)
+ sample_means <- c(sample_means,mean(sample))
+ }
> hist(sample_means,freq=F)
> lines(density(sample_data),lwd=2)