Exam 15: Time Series Analysis and Forecasting

Quarterly revenues (in $1,000,000's) for a national restaurant chain for a five-year period were as follows: ​ a.Solve for the forecast equation that minimizes the sum of squared error. b.Forecast the four quarters of year 6.

Monthly sales at a coffee shop have been analyzed. The seasonal index values are and the trend line is 74123 + 26.9(t). Assume there is no cyclical component and forecast sales for year 8 (months 97 - 108).

The mean squared error is influenced much more by large forecast errors than is the mean absolute error.

With fewer periods in a moving average, it will take longer to adjust to a new level of data values.

A hospital records the number of floral deliveries its patients receive each day. For a two-week period, the records show 15, 27, 26, 24, 18, 21, 26, 19, 15, 28, 25, 26, 17, 23 Use exponential smoothing with a smoothing constant of .4 to forecast the number of deliveries.

Quarterly billing for water usage is shown below. ​ ​ a. Solve for the forecast equation that minimizes the sum of squared error. b. Forecast the summer of year 5 and spring of year 6.

All of the following are true about a stationary time series except

If a time series has a significant trend pattern, then one should not use a moving average to forecast.

Trend in a time series must be linear.

If data for a time series analysis is collected on an annual basis only, which pattern does not need to be considered?

Time series data can exhibit seasonal patterns of less than one month in duration.

Exponential smoothing with α = .2 and a moving average with n = 5 put the same weight on the actual value for the current period.

?Whenever a categorical variable such as season has k levels, the number of dummy variables required

Sales (in thousands) of the new Thorton Model 506 convection oven over the eight-week period since its introduction have been as follows: ​ a. Which exponential smoothing model provides better forecasts, one using α = .6 or α = .2? Compare them using mean squared error. b. Using the two forecast models in part (a), what are the forecasts for week 9?

All of the following are true about a cyclical pattern except

What is a stable time series, and what forecasting methods are appropriate for one?​

The number of cans of soft drinks sold in a machine each week is recorded below. Develop forecasts using a three-period moving average. 338, 219, 278, 265, 314, 323, 299, 259, 287, 302

​When using a moving average of order k to forecast, a small value for k is preferred if only the most recent values of the time series are considered relevant.

In situations where you need to compare forecasting methods for different time periods, the most appropriate accuracy measure is

A four-period moving average forecast for period 10 would be found by averaging the values from periods 10, 9, 8, and 7.