Scientists hypothesized that dietary fiber would impact the blood cholesterol level of college students. They collected data and found r = –0.45 with a scattered residual plot. Interpret in context.

Answer 1

The value of 'r' represents the correlation coefficient where we want to see how dietary fiber intake and blood cholesterol level for college students are related. Since r = -0.45, there is a negative and moderate relationship between the two sets of data. When the amount of dietary fiber increases, the blood cholesterol level tends to decrease, and vice versa.

One thing to keep in mind is that correlation doesn't mean causation. We don't know if dietary fiber will cause a change in blood cholesterol levels.