You can use the events feature of Predictor to define identifiable occurrences that have affected historical data and could affect predicted data. These events can be one-time occurrences, such as a storm, or events that repeat on a regular basis, such as quarterly sales promotions. You can also define events that repeat at irregular intervals, such as assembly-line lockouts or tagouts. Notice that these events are different from unusual values without a known cause discussed in Viewing Screened Data.
You can define events for historical and predicted data. If an event is defined only for historical data, Predictor calculates changes produced by a defined event and uses that information to minimize the effect of the event on data predictions. If an event is defined for historical and predicted data ranges, historical data is used to predict data for the same event in the future.
To add, edit, delete, and view events, in Data Attributes, click View Events. The Historical Data - Events dialog opens (Figure 4, Historical Data - Events Dialog with an Event Added).
Historical Data - Events contains:
Series chart, upper-left corner—Plots historical data values for the selected series; defined events are indicated by vertical bars.
Click the Zoom button at the bottom of the chart beneath the y-axis to contract and expand the x-axis and show more or fewer time periods per unit of length.
Events list—Lists events by number, name, duration, and date. A check box indicates whether the event applies to all series or just the selection. Use the buttons to add, edit, or delete events. For details, see the following:
Note:
Events cannot overlap. At least one time period must not be defined as an event. If more than 10 percent of the historical values are defined as events, predictive accuracy can be affected. A warning message is displayed, but you can still choose to complete the forecast.
Series list, lower-left corner—Lists all the data series in the selected spreadsheet cell range. The currently selected series is displayed in the chart.
Statistics, upper-right corner—Lists the following: number of historical data values, minimum value, mean value, maximum value, standard deviation of values, and the number of time periods in a cycle, such as 12 months in a year.
Copy and print the chart (Edit menu)
Switch among the historical data chart and a data table (View menu)
Show and hide statistics (View menu)
Set chart preferences (Preferences menu)
Open Predictor help (Help menu)
Tip: | You can view information for another data series by selecting it from the Series list. |
After you define at least one event and select Include Events in Data Attributes, you can include events data in reports and extract events data. For instructions, see Creating Reports and Extracting Results Data.