Accordion Center is a nationwide chain of music stores catering to accordion and concertina players. They have sampled one week's revenue for 65 of their stores. The sales data, together with demographic and economic data for each store's sales area were also recorded. A regression model was run to try to explain weekly sales (the variableSalesmeasured in 000s of dollars), making use of population density (the variablePopmeasured in 000s of individuals per square mile living in the area adjacent to the store), the number of competitors located within 10 miles of the store (the variableCompin number of stores) and a dummy variable that is equal to 1 if the store is located in a coastal state (either east, west or gulf coasts) or 0 if the store is located in a city in an inland state (the variableCoast). The regress output for the model is given below.

Dependent Variable: Sales Independent Variables: Coast Comp Pop Regression Statistics Multiple R R Square Adj.RSqr Std.Err. # Cases 0.853 0.727 0.713 35.208 65 Summary Table Variable Coeff. Std.Err. Intercept 127.491 17.424 Coast 18.527 10.423 Comp -22.126 2.542 Pop 3.463 0.498 Analysis of Variance Source df Sum Sqrs Mean Sqr F P-value Regression 3 201 168.398 67056.133 54.094 0.000 Residual 61 75616.599 1239.616 Total 64 276784.997