Exam 15: Multiple Regression and Model Building

When deseasonalizing a time series observation,the actual time series observation is divided by its seasonal factor.

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 Absolute Deviation (MAD).

The forecaster who uses MSD (mean squared deviations)to measure the effectiveness of forecasting methods would prefer method 1,which results in several smaller forecast errors,to method 2,which results in one large forecast error equal to the sum of the absolute values of several small forecast errors given by method 1.

While a simple index is calculated by using the values of one time series,an aggregate index is computed based on the accumulated values of more than one time series.

The simple moving average method is primarily useful in determining the impact of trend on a time series.

The ___________ component of a time series reflects the long-run decline or growth in a time series.

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

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

Two forecasting models were used to predict the future values of a time series.The forecasts are shown below with the actual values. Calculate the mean absolute deviation (MAD)for Model 2.

A positive autocorrelation implies that negative error terms will be followed by _________ error terms.

Given the following data,compute the mean absolute deviation.

The no-trend time series model is given by

Consider a time series with 15 quarterly sales observations.Using the quadratic trend model,the following partial computer output was obtained. Write the prediction equation.

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

Since a(n)____________ index employs the base-period quantities in all succeeding periods,it allows for ready comparisons for identical quantities of goods purchased between the base period and all succeeding periods.

Consider the following data. Using simple exponential smoothing with α = 0.2,determine the forecast error for time period 1.

In the Durbin-Watson test,if the calculated d-statistic is greater than the upper value of the d-statistic,then

The ________ component of a time series measures the fluctuations in a time series due to economic conditions of prosperity and recession with a duration of approximately 2 years or longer.

Consider the following data and calculate S₂ using simple exponential smoothing and α = 0.3.

A simple index is computed by using the values of one time series,while a(n)___________ index is based on a "market basket" consisting of more than one time series.