A plastics manufacturing performed a quarterly time series analysis for demands

# A plastics manufacturing performed a quarterly time

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22. A plastics manufacturing performed a quarterly time series analysis for demands over the lastfive years (periods 1 through 20). The analysis resulted in the following trend equation and seasonal indexes:= 920.0 + 22.6 tBased on the seasonal indexes, which quarter is expect to have 21% more demand than predictedby the trend line? 23. A plastics manufacturing performed a quarterly time series analysis for demands over the last= 920.0 + 22.6 tUsing the trend line question and the seasonal indexes, predict demand for the third period of the next year, i.e., period 23. 24. i. Each typical seasonal index is a percent with the average for the year equal to 100.ii. The ratio-to-moving-average method eliminates the seasonal, cyclical and irregular components from the original data (y).iii. The trend component of a time series is obtained my minimizing the sum of the squares of theerrors. 25. i. In the ratio-to-moving-average procedure, using the median or modified mean eliminates trend.ii. A typical seasonal index of 103.7 for January indicates that sales for January are below the annual average.iii. The total of the four typical quarterly indexes should equal 100.0. A. (i), (ii), and (iii) are all correct statements.B. (i) and (ii) are correct statements but not (iii).C. (i) and (iii) are correct statements but not (ii).D. (ii) and (iii) are correct statements but not (i).E.(i), (ii), and (iii) are all false statements. 26. i. A typical monthly seasonal index of 107.0 indicates that sales (or whatever the variable is) are 7 percent above the annual average.ii. For a quarterly time series, the initial step, using the ratio-to-moving average method, is to remove the seasonal components from the time series using a 3-month centered moving average.iii. In the final step, using the ratio-to-moving-average method on quarterly data, the total of the modified means should theoretically be equal to 400 because the average of should be 100.  • • • 