ABSTRACT
Let’s return to the example that was used in Chapter 1, in which we were curious about the effect on math achievement of time spent on math homework. Given our finding of a statistically significant effect, you might reasonably have a chat with your daughter about the influence of homework on achievement. You might say something like “Lisa, these data show that spending time on math homework is indeed important. In fact, they show that for each additional hour you spend on math homework every week, your achievement test scores should go up by approximately 2 points. And that’s not just grades but test scores, which are more difficult to change. So, you say you are now spending approximately 2 hours a week on math homework. If you spent an additional 2 hours per week, your achievement test scores should increase by about 4 points; that’s a pretty big improvement!”1
