Concept explainers
The district manager of Jasons, a large discount electronics chain, is investigating why certain stores in her region are performing better than others. She believes that three factors are related to total sales: the number of competitors in the region, the population in the surrounding area, and the amount spent on advertising. From her district, consisting of several hundred stores, she selects a random sample of 30 stores. For each store, she gathered the following information.
y = total sales last year (in $ thousands)
x1 = number of competitors in the region
x2 = population of the region (in millions)
x3 = advertising expense (in $ thousands)
The results of a multiple
- a. What are the estimated sales for the Bryne store, which has four competitors, a regional population of 0.4 (400,000), and an advertising expense of 30 ($30,000)?
- b. Compute the R2 value.
- c. Compute the multiple standard error of estimate.
- d. Conduct a global test of hypothesis to determine whether any of the regression coefficients are not equal to zero. Use the .05 level of significance.
- e. Conduct tests of hypothesis to determine which of the independent variables have significant regression coefficients. Which variables would you consider eliminating? Use the .05 significance level.
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Chapter 14 Solutions
STAT TECH IN BUSINESS & ECON AC
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