Salmons Stores operates a national chain of women's apparel stores. Five thousand copies of an expensive four-color sales catalog have been printed, and each catalog includes a coupon that provides a $50 discount on purchases of $200 or more. Salmons would like to send the catalogs only to customers who have the highest probability of using the coupon. The data file SalmonsPreview the document contains data from an earlier promotional campaign. For each of 1,000 Salmons customers, three variables are tracked: last year's total spending at Salmons, whether they have a Salmons store credit card, and whether they used the promotional coupon they were sent.

Use logistic regression to classify observations as a promotion-responder or not by using Spending and Card as input variables and Coupon as the output variable.

a. Interpret the meaning of the first-decile lift in the decile-wise lift chart on the test set.
b. Create a partition of the data with all the tracked variables where 75% of observations are in the training set and 25% in the validation set. What is the corresponding logistic classification rule, the confusion matrix and the Accuracy of the model?
c. Classify those two customers: Paul who spent $8,000 at Salmons but does not have the store credit card and Jessica who spent $3000 and has the store credit card?