Research question: On average, are husbands older than their wives?
Step 1: The data are paired by couple. This is a paired means test.
\(H_a: \mu_d > 0\)
Step 2: We constructed a randomization distribution in StatKey using the built in dataset.
Step 3: \(p < 0.001\)
Step 4: Reject the null hypothesis
Step 5: There is evidence that in the population, on average, husbands are older than their wives.