PROBLEM 8: TIME SERIES ANALYSIS AND FORECASTING

Consider the Wacker Distributors sales of CD players shown in the table below forthe years 2018 through 2021.

YEARQUARTERSALES (MILLIONS OF DOLLARS)20181116212231454126201911132124316341222020112521343181412720211115214331724121

Q1. Determine the Ratio-to-Moving-Average for the Quarterly Sales Data?

Q2. Determine the Adjustment Factor and Seasonal Index, using the appropriate table?

Q3. Determine the Cyclical Relative, using the appropriate table?

Q4. Determine the yearly trend equation and calculations of Y (Y-predicted), and then plot and explain the cyclical Relative using the relevant chart?

Q5. Using the quarterly formula, step down the trend equation developed earlier so that it is expressed in terms of quarters rather than years. Also, adjust the equation so that the trend values are in thousands of dollars instead of millions of dollars. Carry the final values to the first place after the decimal point?

Q6. Write the modified quarterly equation?

Q7. Write the quarterly trend equation (in units of thousands of dollars)?

Q8. Forecast the level of quarterly sales for each quarter of 2022?

Q9. Given the sales data (in millions of dollars), as presented earlier, determine, by means of the Method of 2-Year Moving Average, the forecast for the year 2022?

Q10. Given the sales data (in millions of dollars) as presented earlier, determine, by means of the Method of Exponential Smoothing, using = 0.30 and = 0.60, the forecast for the year 2022?

Q11. For each of the methods shown above: determine SSE, MSE, and RMSE, and state which method provides the best estimate?

2-Year Moving Average Method of Exponential Smoothing, for = 0.30 and = 0.60 Trend Equation