# Goals: Do bootstrap inference, as an example, for a sample median. library(boot) samplemedian <- function(x, d) { # d is a vector of integer indexes return(median(x[d])) # The genius is in the x[d] notation } data <- rnorm(50) # Generate a dataset with 50 obs b <- boot(data, samplemedian, R=2000) # 2000 bootstrap replications cat("Sample median has a sigma of ", sd(b$t[,1]), "\n") plot(b) # Make a 99% confidence interval boot.ci(b, conf=0.99, type="basic")