13.2 Limited-time offer effect on purchase intent, continued. Refer to the previous exercise. The following table summarizes the group means and standard deviations.

Light userHeavy user
Advertisementss
Regular4.561.755.001.79
Added wording5.741.195.191.91

  1. (a) Is it reasonable to pool the standard deviations for these data? Explain your answer.

  2. (b) For each parameter in your model from Exercise 13.1, give the estimate.