Role of retailer interest on shopping behavior. Retail interest is defined by marketers as the level of interest a consumer has in a given retail store. Marketing professors at the University of Tennessee at Chattanooga and the University of Alabama investigated the role of retailer interest in consumers' shopping behavior (Journal of Retailing, Summer 2006). Using survey data collected for n = 375 consumers, the professors developed an interaction model for y = willingness of the consumer to shop at a retailer's store in the future (called ‘‘repatronage intentions'') as a function of x₁ = consumer satisfaction and x₂ = retailer interest. The regression results are shown below.

(a) Is the overall model statistically useful for predicting y? Test using α = .05.

(b) Conduct a test for interaction at α = .05.

(c) Use the β-estimates to sketch the estimated relationship between repatronage intentions.

(y) and satisfaction (x₁) when retailer interest is x₂ = 1 (a low value).

(d) Repeat part c when retailer interest is x₂ = 7 (a high value).

(e) Sketch the two lines, parts c and d, on the same graph to illustrate the nature of the interaction.