After six months of operation, the observed sales of ice cream (in dollars) and the number of park attendees are Month 1 2 3 4 5 6 Ice cream sales 325 335 172 645 770 950 Park attendees 880 976 440 1,823 1,885 2,436

a. Determine a regression equation treating ice cream sales as the dependent variable and time as the independent variable. Based on this regression equation, what should the dollar sales of ice cream be in two years (month 30)? How confident are you about this forecast? Explain your answer.

b. Determine a regression equation treating ice cream sales as the dependent variable and park attendees as the independent variable. (Hint:You will require the general regression equations in Appendix 2–B in order to solve this part.)

c. Suppose that park attendance is expected to follow a logistic curve (see Figure 2–24).
The park department expects the attendance to peak out at about 6,000 attendees per month. Plot the data of park attendees by month and “eyeball”
a logistics curve fit of the data using 6,000 as your maximum value. Based on your curve and the regression equation determined in part (b), predict ice cream sales for months 12 through 18.