A survey was taken of students at a large university in the fall of 2003; among other things, students were asked to report their weight and how many minutes of television they had watched the day before.
a. If we take TV times as the explanatory variable, are we implying that watching a lot of TV could make you heavier, or that people who are heavier tend to watch more TV?
b. If weights were taken as the explanatory variable instead of TV times, which of these would change: the equation of the regression line, the value of the correlation, or both, or neither?