The safety division at Acme Manufacturing Company has written the following numbers of safety citations in the past seven months:
a. Using the eyeball method, plot the data and project the number of citations that might be expected next month.
b. The chief safety inspector suspects that safety citations are related to number of new hires. She has collected the following data on new hires for the same seven months.
c. Calculate the formula for the straight line of best fit (line of regression) for the last seven months of citations. Use the formula to calculate the projected demand for the next two months.
d. Calculate the coefficient of correlation between new hires and citations. Make the same calculation but with new hires leading citations by one month. (Base the calculations on citations for months -6 and -1 and new hires for months -7 to -2.) Comment on the difference and on which type of associative forecast is more appropriate.