Exam 18: Time Series and Forecasting

A useful method for eliminating fluctuations in a time series is computing a ______.

Product sales since 1999 are: The least squares trend equation is given as: Ŷ = 265.12 - 21.18t, where t is set equal to 1 for 1999. What are the predicted sales for 2009?

For a time series beginning with 1991 and extending up to 2010, which year would be coded with a one when using the coded method?

The Durbin-Watson statistic is used to test for correlated residuals.

For the third quarter, the sales are 1,000 units; the seasonal index for the quarter is 1.10. What are the deseasonalized sales for the quarter?

A linear trend equation is used to represent time series values when the data are changing by equal what?

Episodic and residual variations can be projected into the future.

In a linear trend equation, t is a coded value that corresponds with a time period in a time series.

A collection of data recorded over a weekly, monthly, quarterly, or yearly time interval is known as ___________.

If a trend equation is Ŷ = 15 + 75t, the periodic increase in the forecast is _____.

What is "a" in the least squares trend equation?

When the null hypothesis is rejected based on the Durbin-Watson statistic, what types of problems occur in regression analysis?

If the least squares equation for sales data going from 2004 to 2008 is Ŷ = 10 + 1.3t (in $millions), what is the value of t and the forecast for 2010?

An analysis of past seasonal fluctuations can be helpful in planning production for items such as toys, dolls, Easter eggs, and other holiday-oriented goods.

Using the following time series data, The quarterly indexes for the year 2010 will total approximately _______.

A plastics manufacturer performed a quarterly time series analysis for demands over the last five years (periods 1 through 20). The analysis resulted in the following trend equation and seasonal indexes: Ŷ = 920.0 + 22.6t Based on the seasonal indexes, which quarter is expected to have 25% less demand than predicted by the trend line?

If the past data approximates a straight line, the equation used is Ŷ = a + bt, where a is the Y-intercept and b is the slope of the line.

Consider a three-year moving average. The weights given to each period are:

If four seasonal indexes are reported for a time series, data is thus reported _________.

For the third quarter, the sales are 1,500 units; the seasonal index for the quarter is 0.90. What are the deseasonalized sales for the quarter?