In the United States, one's SAT score may be used as a "proxy" measure of one's social class. What does this mean?

Question

Quizplus · Accepted Answer

The SAT exam is strongly correlated to family income, meaning that those from wealthier families tend to score higher on the exam. Therefore, one's SAT score can be used as a proxy measure of one's social class. However, it is important to note that this does not mean that SAT scores are a perfect measure of social class, as there are many other factors that can influence one's score.

In the United States, One's SAT Score May Be Used