# solution

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. How does the frequency that a supermarket product is promoted at a discount affect the price that customers expect to pay for the product? Does the percent reduction also affect this expectation? These questions were examined by researchers in a study that used 160 subjects. The treatment conditions corresponded to the number of promotions (1, 3, 5, or 7) that were described during a 10-week period and the percent that the product was discounted (10%, 20%, 30%, and 40%). Ten students were randomly assigned to each of the 4 Ã— 4 = 16 treatments.22

(a) Plot the expected price versus the number of promotions. Do the same for expected price versus discount. Summarize the

results.

(b) These data come from a designed experiment with an equal number of observations for each promotion by discount combination. Find the means and standard deviations for expected price for each of these combinations. Describe any patterns that are evident in these summaries.

(c) Using your summaries from part (b), make a plot of the mean expected price versus the number of promotions for the 10%

discount condition. Connect these means with straight lines. On the same plot add the means for the other discount conditions.

Summarize the major features of this plot

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