Refer to the analyses in Section 1.5.3 for the horseshoe crab satellites.

a. With color alone as a predictor, why are standard errors much smaller for a Poisson model than for a normal model? Out of these two very imperfect models, which do you trust more for judging significance of the estimates of the color effects? Why?

b. Download the data (file Crabs.dat) from www.stat.ufl.edu/~

aa/glm/data. When weight is also a predictor, identify an outlying observation. Refit the model with color and weight predictors without that observation. Compare results, to investigate the sensitivity of the results to this outlier.