The article “Effects of Gamma Radiation on Juvenile and Mature Cuttings of Quaking Aspen” (Forest Science [1967]: 240–245) reported the following data on x = exposure to radiation (kR/6 hours) and y = dry weight of roots (mg):

a. Construct a scatterplot for these data. Does the plot suggest that the simple linear regression model might be appropriate?

b. The estimated regression line for these data is ŷ =  127 − 6.65x and the standardized residuals are as given.

Construct a standardized residual plot. What does the plot suggest about the adequacy of the simple linear regression model?

Transcribed Image Text:

X y 0 110 2 123 4 119 6 86 8 62