The paper “Accelerated Telomere Shortening in Response to Life Stress” (Proceedings of t...

The paper “Accelerated Telomere Shortening in Response to Life Stress” (Proceedings of the National Academy of Sciences [2004]: 17312–17315) described a study that examined whether stress accelerates aging at a cellular level. The accompanying data on a measure of perceived stress (x) and telomere length ( y) were read from a scatterplot that appeared in the paper. Telomere length is a measure of cell longevity.

a. Compute the equation of the least-squares line.

b. What is the value of r ²?

c. Does the linear relationship between perceived stress and telomere length account for a large or small proportion of the variability in telomere length? Justify your answer.