Fictitious data on specimens tested by two methods

Description

stdtest has been done on everyone, and sampledtest has been done on a stratifed subsample of 275 out of 402 specimens (is NA on the other 127 specimens)

Usage

data(specimens)

Format

A data frame with 402 observations on the following 3 variables.

stratum

6 strata used for sampling

stdtest

standard test result available on all specimens

sampledtest

new test result available only on stratified subsample

Examples

data(specimens)