R Statistics Cookbook

How to do it...

In the following example, we will load performance indexes from 80 employees (before and after a new bonus scheme was announced). We want to test whether the bonus has produced an improvement in performance. In this case, the null hypothesis will be that the performance change is smaller than zero or equal to zero, versus greater than zero:

1. Load the data, as follows:

data = read.csv("./paired_scores.csv")

2. Perform the paired t-test:

t.test(data$post_bonus,data$pre_bonus,conf.level = .95,alternative="greater",paired=TRUE) 

The preceding code generates the following output:

3. The mean of the differences is 2.31, which generates ...