Exam 17: Time Series Forecasting and Index Numbers

Consider the quarterly production data (in thousands of units) for the XYZ manufacturing company below. Calculate the 4-period (quarter) moving average for the entire time series.

When using moving averages to estimate the seasonal factors, we need to compute the centered moving average if there is an odd number of seasons.

Consider the quarterly production data (in thousands of units) for the XYZ manufacturing company below, followed by the centered moving average values and their respective periods. Calculate the average seasonal factor for each quarter ( _t).

Based on the following data, a forecaster used simple exponential smoothing and determined the following: S₀ = 19, S₁ = 18.6, S₂ = 19.08, S₃ = 19.064, S₄ = 19.851, and S₅ = 19.481. Calculate the Mean Squared Deviation (MSD or MSE).

Which of the following time series forecasting methods would not be used to forecast a time series that exhibits a linear trend with no seasonal or cyclical patterns?

A Paasche index more accurately provides a year-to-year comparison of the annual cost of selected products in the market basket than a Laspeyres index.

A sustained long-term change in the level of the variable that is being forecasted per unit of time is

When a forecaster uses the ________ method, she or he assumes that the time series components are changing quickly over time.

The basic difference between MAD and MSE is that MSE, unlike MAD, penalizes a forecasting technique much more for ________ errors than for ________ errors.

Dummy variable regression would be an appropriate method to use to forecast a time series that exhibits a linear trend with no seasonal or cyclical patterns.

Given the following data, compute the mean squared deviation (error).

Based on the quarterly production data (in thousands of units) for the XYZ manufacturing company, the average seasonal factor ( _t) is .986 for winter, .915 for spring, 1.125 for summer, and .925 for fall. Determine the normalized (adjusted) seasonal factors for each quarter.

In the multiplicative decomposition method, the centered moving averages provide an estimate of a trend's ________.

The ________ component of a time series consists of erratic and unsystematic fluctuations in the time series data.

Consider the following data. Calculate S₀ using simple exponential smoothing and α =.2.

Exponential smoothing is a forecasting method that applies equal weights to the time series observations.

Assume that the current date is February 1, 2003. The linear regression model was applied to a monthly time series based on the last 24 months' sales (from January 2000 through December 2002). The following partial computer output summarizes the results. At a significance level of .05, what is the value of the rejection point in testing the slope for significance?

When the magnitude of the seasonal swing does not depend on the level of a time series, we call this ________ variation.

Trend refers to a long-run upward or downward movement of a time series over a period of time.

The Holt-Winters double exponential smoothing method is used to forecast time series data with ________.