PMBA 6331 Problem Set 6 The \"oligopoly.dta\" attached give quarterly sales of the popular game Oligopoly at the J-Mart variety store. Please use the multiplicative decomposition method to forecast Oligopoly sales for year 4. a. Compute appropriate 4-period moving averages for these data. b. Compute centered moving averages for these data. c. Calculate d. e. f. g. sn tirt values for these data. Calculate estimates of the seasonal factors for quarterly Oligopoly sales. Compute the deseasonalized observations for these data. Plot the deaseasonalized observations versus time. What kind of trend appears to exist? Assuming a linear trend TR t = 0+ 1 t Compute point estimates for B0 and B1. h. Compute i. j. cl tirt values for the Oligopoly data. Compute estimates of the cyclical factors for the Oligopoly data. Compute forecasts of Oligopoly sales for the four quarters of year 4. NB: Use Stata whenever possible \"Oligopoly.dta\" Data set