Final answer:
To compare 2 dependent groups or multiple measurements over time, use a matched pairs test. Take measurements from the same group at different times, calculate the differences, and use them in the hypothesis test.
Step-by-step explanation:
When comparing 2 dependent groups or more than multiple measurements over time, you can use a matched pairs test. This involves taking measurements from the same group of individuals or objects at different points in time. Then, the differences between the measurements are calculated and used for the hypothesis test. The differences should either come from a normally distributed population, or the number of differences should be large enough for the sample mean of differences to be approximately normal.