4. The data set dat_pre_post simulates pre-intervention measurements for 130

individuals together with their post-intervention measurements. Carry out the most

powerful applicable test we have learned of the null hypothesis that the intervention is

not associated with any systematic increase or decrease in the measurement. Please

justify your choice of test. (Note that to have evidence that any change was caused by

the intervention, a controlled experiment would be required.) To help you decide

which test to use, please generate a scatter plot of the pre values against the post

values. (10 points)

load ("dat_pre_post.RData")