Exam 11: Time Series Forecasting

Exhibit 11.24 The following questions use the data below. A store wants to predict quarterly sales. The owners have has collected 3 years of sales data and wants your help in analyzing the data. They want to use a quadratic trend model with seasonality to forecast sales. -Refer to Exhibit 11.24. Based on the regression output, what formulas should go in cells D3:H21?

Exhibit 11.1 The following questions use the data below. Honest Al's Used Cars wants to predict how many cars are sold each month. He has collected data for 12 months. He needs your help in analyzing this data using moving averages. -Refer to Exhibit 11.1. What Excel function will compute the root mean squared error in cell C18 of the spreadsheet?

Which of the following statements are true regarding the difference between forecasts using exponential smoothing and forecasts using a weighted moving average method?

Why might we not be able to build a regression model to predict a dependent variable?

Exhibit 11.4 The following questions use the data below. Joe's Sporting Goods wants to forecast quarterly sales figures using the additive seasonal method. The store has collected 12 quarters of data and needs your help to analyze the data. -Refer to Exhibit 11.4. What formula should be entered in cell E3 to compute the base level when using the additive seasonal effects method?

Exhibit 11.23 The following questions use the data below. A store wants to predict quarterly sales. The owner has collected 3 years of sales data and wants your help in analyzing the data. He wants to use a quadratic trend model to forecast sales. -Refer to Exhibit 11.23. Based on the regression output, what formulas should go in cells D3:F14?

In stationary time series there is no significant upward or downward trend in the data over time.

Why might a forecaster calculate MSE values on just the most recent data in the time-series data set?

Exhibit 11.9 The following questions use the data below. Joe's Sporting Goods wants to forecast quarterly sales figures using a linear trend model. The store has collected 12 quarters of data and needs your help to analyze the data. The relevant regression output is in the following table. -Refer to Exhibit 11.9. What are predicted sales for the fourth quarter of year 4?

Seasonality is defined as

Exhibit 11.12 The following questions use the data below. Joe's Sporting Goods wants to forecast quarterly sales figures using a seasonal regression model. The store has collected 12 quarters of data and needs your help to analyze the data. The relevant regression output is provided in the following table. -Refer to Exhibit 11.12. What is the Input X Range in the Regression command settings dialog box?

Exhibit 11.2 The following questions use the data below. Honest Al's Used Cars wants to predict how many cars are sold each month. He has collected data for 12 months. He needs your help in analyzing this data using weighted moving averages. -Refer to Exhibit 11.2. What formula should be entered in cell C6 to compute the 2-month weighted moving average forecast for month 3?

Exhibit 11.4 The following questions use the data below. Joe's Sporting Goods wants to forecast quarterly sales figures using the additive seasonal method. The store has collected 12 quarters of data and needs your help to analyze the data. -Refer to Exhibit 11.4. What are predicted sales for time period 13 using the data in the spreadsheet?

Exhibit 11.3 The following questions use the data below. Honest Al's Used Cars wants to predict how many cars are sold each month. He has collected data for 12 months. He needs your help in analyzing this data using exponential smoothing. -Refer to Exhibit 11.3. Assume the forecasted value for month 13 is 79.64. What is the forecasted value for month 16?

Exhibit 11.7 The following questions use the data below. Joe's Sporting Goods wants to forecast quarterly sales figures using Holt's method. The store has collected 12 quarters of data and needs your help to analyze the data. -Refer to Exhibit 11.7. What formula should be entered in cell E4 to compute the base level when using Holt's method?

Exhibit 11.12 The following questions use the data below. Joe's Sporting Goods wants to forecast quarterly sales figures using a seasonal regression model. The store has collected 12 quarters of data and needs your help to analyze the data. The relevant regression output is provided in the following table. -Refer to Exhibit 11.12. What formula should be entered in cell I3 to compute the Seasonal Value for year 1 Quarter 1?

Exhibit 11.11 The following questions use the data below. Joe's Sporting Goods wants to forecast quarterly sales figures using seasonal indices. The store has collected 12 quarters of data and needs your help to analyze the data. The relevant regression output is in the following table. -Refer to Exhibit 11.11. What are predicted sales for the first quarter of year 4?

Exhibit 11.22 The following questions use the data below. A store wants to predict quarterly sales. The owner has collected 3 years of sales data and wants your help in analyzing the data. He wants to use regression and a linear trend model. -Refer to Exhibit 11.22. Based on the regression output, what formulas should go in cells E3:E14?

The correct formula for the weighted moving average extrapolation technique with different weights is

Exhibit 11.10 The following questions use the data below. Joe's Sporting Goods wants to forecast quarterly sales figures using a quadratic trend model. The store has collected 12 quarters of data and needs your help to analyze the data. The relevant regression output is in the following table. -Refer to Exhibit 11.10. What is the Input Y Range in the Regression command settings dialog box?