Exam 15: Forecasting

A time series model with a seasonal component will always involve quarterly data.

The forecasting method that is appropriate when the time series has no significant trend, cyclical, or seasonal effect is

Use the following to forecast a value for period 14, a second quarter. T = 16.32 - .18(t) C₂ = .91 S₂ = .75

The trend component is easy to identify by using

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

Seasonal components with values above 1.00 indicate actual values below the trend line.

A trend line for the attendance at a restaurant's Sunday brunch is given by Number = 264 + .72(t) How many guests would you expect in week 20?

The number of properties newly listed with a real estate agency in each quarter over the last four years is given. Calculate the seasonal index values. Year Quarter 1 2 3 4 1 73 81 76 77 2 89 87 85 92 3 123 115 108 131 4 92 93 87 101

Short-term, unanticipated, and nonrecurring factors in a time series provide the random variability known as

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

Qualitative forecasting techniques should be applied in situations where time series data exists, but where conditions are expected to change.

Quantitative forecasting methods do not require that patterns from the past will necessarily continue in the future.

Explain how qualitative methods frequently incorporate the opinions of multiple analysts.

Trend in a time series must be linear.

If the random variability in a time series is great, a high $\alpha$ 0 value should be used to exponentially smooth out the fluctuations.

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

Using exponential smoothing, the demand forecast for time period 10 equals the demand forecast for time period 9 plus

One measure of the accuracy of a forecasting model is the

Any recurring sequence of points above and below the trend line lasting less than one year can be attributed to the cyclical component of the time series.

Time series methods