X12 Procedure

The following new features have been added to the X12 procedure:

• The PLOTS option in the PROC X12 statement now includes forecast plots. You can now request four different plots for the forecast series on the original scale, and if the series is transformed, on the transformed scale. The following values can be specified in PLOTS=FORECAST(value-list):

  FORECAST

  plots the actual time series and its one-step-ahead forecasts over the historical period, and plots the forecast and its confidence bands over the forecast horizon.

  FORECASTONLY

  plots the forecast and its confidence bands over the forecast horizon only.

  MODELS

  plots the one-step-ahead model forecast and its confidence bands in the historical period.

  MODELFORECASTS

  plots the one-step-ahead model forecast and its confidence bands in the historical period, and plots the forecast and its confidence bands over the forecast horizon.

  TRANSFORECAST

  plots the transformed time series and its one-step-ahead forecast over the historical period, and plots the forecast and its confidence bands over the forecast horizon.

  TRANSFORECASTONLY

  plots the forecast of the transformed series and its confidence bands over the forecast horizon only.

  TRANSMODELS

  plots the one-step-ahead model forecast of the transformed series and its confidence bands in the historical period.

  TRANSMODELFORECASTS

  plots the one-step-ahead model forecast of the transformed series and its confidence bands in the historical period, and plots the forecast and its confidence bands over the forecast horizon.

• The following new values are available in the PRINT= option in the AUTOMDL statement:

  ALL

  specifies that all automatic modeling output be displayed.

  NONE

  suppresses all display of automatic modeling output.

  ONLY

  specifies that only the requested automatic modeling tables be displayed.

• The following new options are available in the FORECAST statement:

  NBACKCAST=

  specifies the number of periods to backcast for regARIMA extension of the series. Backcasting has been shown to improve seasonal adjustment for short series.

  OUT1STEP

  specifies that the one-step-ahead forecasts be computed and displayed in addition to the multistep forecasts. The one-step-ahead forecasts and associated statistics are useful in evaluating the ARIMA model.

  OUTBACKCAST

  includes backcasts in certain tables that are sent to the output data set.

  OUTFORECAST

  includes forecasts in certain tables that are sent to the output data set. This option is an alias of the OUTFORECAST option in the X11 statement.

• The FINAL=USER option in the X11 statement specifies that user-defined regressors are to be removed from the final seasonally adjusted series.

• The YEARSEAS option in the OUTPUT statement specifies that variables containing values for year and season are included in the OUT= data set. These values are useful when creating seasonal plots.

• An auxiliary variable has been added to forecast data sets that are available through ODS OUTPUT. The variable _SCALE_ indicates whether the observation refers to the original series, "Original," or the transformed series, "Transformed." The variable helps you subset the output when the series is transformed.