Reducing tobacco retail sales. New Zealand has set a goal of being smoke-free by the year 2025. Research published in the Australian and New Zealand Journal of Public Health (February 2020) investigated limiting tobacco sales outlets to pharmacies, liquor stores, or gas stations. The data collected for a sample of n = 870 liquor stores included a measure of socioeconomic deprivation for the store area on a 10-point scale, where 1 = the least deprived area and 10 = the most deprived area. Socioeconomic deprivation (x) was used to forecast the number (y) of liquor stores selling tobacco using simple linear regression. The estimated model resulted in an SSE value of 2,222.

a. Compute s2 and s for this model.

b. Which of the two values in part a can be interpreted practically? Give the interpretation in the context of the problem.

c. A similar model was fit to data collected at 1,035 pharmacies. The estimated standard deviation of error for this model was s = 2.84. Interpret this result practically.

d. Which of the two models will have smaller forecast errors? Explain.