Paired t
The Paired t conducts a hypothesis test of the difference between two population means when observations are paired. It also calculates a confidence interval of the difference. This procedure is based on the t-distribution which is derived from a normal distribution. It is appropriate when the paired differences follow a normal distribution. If the observations are dependent in a pairwise manner, the matching results in smaller variance and greater power of detecting differences than the 2-sample t.
Test | Null Hypothesis, H0 | Alternate Hypothesis, H1 |
One-tailed | μd = μD | μd < μD or μd > μD |
Two-tailed | μd = μD | μd ≠ μD |
where μd is the population mean of the differences and μD is the hypothesized mean of the differences