Question

Example An article in Wear presents data on the fretting wear of mild steel and oil viscosity. Representative data follow with X: oil viscosity and Y: wear volume 10 cubic millimeters solve by hand X 240 181 193 155 172 110 113 75 94 Y 1.6 9.4 15.5 20 22 35.5 43 40.5 33 1. 2. Construct a scatter plot. Does a simple linear regression model appear to be plausible? Find the correlation 3. 4, Fit the simple linear regression model Find the estimate of σ2

Answer 1

1)

1. scatter-plot shows an approximate linear relationship.from above scatter-plot it seems they are negatively related

2)

3)

4)