Suppose you wanted to compare students in two different clas

Suppose you wanted to compare students in two different classes, assessing whether research methods or social psychology leads to more favorable ratings of how interesting psychology is.

Why would it be important to consider selection, attrition, and history?

Solution

because these are factor that you need to know when you want to do a test,

the selection because we want a test that is always random

history we need to know why the variables have that behavior, what would you expect to see