Forecasts

The Forecast tab of the Time Intervals node allows you to specify the number of records you want to forecast and to specify future values for use in forecasting by downstream Time Series modeling nodes or Streaming TS nodes. These settings may be overridden in downstream nodes as needed, but specifying them here may be more convenient than specifying them for each node individually.

Extend records into the future. Specifies the number of records to forecast beyond the estimation period. Note that these records may or may not be "forecasts" depending on the number of holdouts that are specified on the Estimation tab.

Future indicator field. Label of the generated field that indicates whether a record contains forecast data. Default value for the label is $TI_Future.

Future Values to Use in Forecasting. For each record that you want to forecast (excluding holdouts), if you are using predictor fields (with the role set to Input), you must specify estimated values for the forecast period for each predictor. You can either specify values manually, or choose from a list.

• Field. Click the field selector button and choose any fields that may be used as predictors. Note that fields selected here may or may not be used in modeling; to actually use a field as a predictor, it must be selected in a downstream modeling node. This dialog box simply gives you a convenient place to specify future values so they can be shared by multiple downstream modeling nodes without specifying them separately in each node. Also note that the list of available fields may be constrained by selections on the Build tab. For example, if Specify fields and functions is selected on the Build tab, any fields not aggregated or padded are dropped from the stream and cannot be used in modeling.

  Note: If future values are specified for a field that is no longer available in the stream (because it has been dropped or because of updated selections made on the Build tab), the field is shown in red on the Forecast tab.

• Values. For each field, you can choose from a list of functions, or click Specify to either enter values manually or choose from a list of predefined values. If the predictor fields relate to items that are under your control, or which are otherwise knowable in advance, you should enter values manually. For example, if you are forecasting next month's revenues for a hotel based on the number of room reservations, you could specify the number of reservations you actually have for that period. Conversely, if a predictor field relates to something outside your control, such as a stock price, you could use a function such as the most recent value or the mean of recent points.

  The available functions depend on the measurement level of the field.

  Table 1. Functions available for measurement levels

  Measurement level	Functions
  Continuous or Nominal field	Blank Mean of recent points Most recent value Specify
  Flag field	Blank Most recent value True False Specify

  Mean of recent points—Calculates the future value from the mean of the last three data points.

  Most recent value—Sets the future value to that of the most recent data point.

  True/False—Sets the future value of a flag field to True or False as specified.

  Specify—Opens a dialog box for specifying future values manually, or choosing them from a predefined list.