Question: A zoologist recorded the average body weight (in kilograms) and the average brain weight (in grams) for 62 species of animals. The data are included in the data set Species.sav.

(a) Obtain a scatterplot of brain weight against body weight. How would you characterize the plot? There are three ‘unusual’ observations. Identify the corresponding species.

(b) Obtain the regression line relating brain weight to body weight. Save the leverages, the studentized deleted residuals, and the Cook’s distances. Explain on the problems caused by the three ‘unusual’ species.