Question: The data in the table come from a study of road conditions in Canada. The variable given are age of a portion of highway (in years) and PCI (pavement condition index), a composite measure of the quality of its surface that incorporates the effects of surface deterioration (potholes, cracks, undulations and other engineering indicators of pavement deterioration).

Age 14,16,12,18,15,13,13,12,11,15,15,15,12,18,13,13

PCI 61,56,75,56,54,57,55,60,68,67,59,59,58,49,54,62

Age 15,11,12,13,13,14,16,16,16,16,14,11,11,18,14,11

PCI 51,60,72,59,55,66,45,63,51,58,71,65,76,53,58,71

Plot PCI verses Age. Describe the plot.

Superimpose the least squares regression line on your plot.

By looking at your plot in a. do you think you could derive a useful rule for replacing highway based on age along? Justify your answer.