EXAMPLE 11 Money Helps SAT Scores?
The College Board, which administers the SAT, offers this information on its website about the Class of 2013 seniors who take the test (the 55% of test-takers who did not respond to this income question had a mean score of 515):
| Family income (in $1000s) | Mean Math SAT score |
|---|---|
| 0–20 | 462 |
| 20–40 | 482 |
| 40–60 | 500 |
| 60–80 | 511 |
| 80–100 | 524 |
| 100–120 | 536 |
| 120–140 | 540 |
| 140–160 | 548 |
| 160–200 | 555 |
| Over 200 | 586 |
This information suggests a strong positive association between the test-taker’s score and family income. But there’s no direct mechanism that causes this association—wealthy families are not sending secret bribes to the College Board. It may simply be that children of wealthy parents are more likely to have advantages, such as well-educated role models, high expectations, access to extra tutoring or test preparation, I smaller class sizes, and schools with more experienced, better qualified teachers.