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