Chapter 10.2, Problem 74E

To determine

To explain why or why not it is appropriate to conclude that the students who reduce this homework time from $120\text{ min to 70 min}$ will likely improve their performance on tests such as those used in this study.

Answer to Problem 74E

No.

Explanation of Solution

In the previous exercise we concluded that there was an association between the homework time and the performance on test such as those used in the study as a homework time over $100\text{ min}$ tends to corresponds with worst test results.

However, association does not causation which means that the decrease in the homework time does not necessarily cause better test results.

For example, it is possible that the people with the long homework time are the people who have learning difficulties and reducing their homework time could then make their test results even worse.