The X12 Procedure

CHECK Statement

  • CHECK options;

The CHECK statement produces statistics for diagnostic checking of residuals from the estimated regARIMA model.

The following tables that are associated with diagnostic checking are displayed in the output: "Autocorrelation of regARIMA Model Residuals," "Partial Autocorrelation of regARIMA Model Residuals," "Autocorrelation of Squared regARIMA Model Residuals," "Outliers of the Unstandardized Residuals," "Summary Statistics for the Unstandardized Residuals," "Normality Statistics for regARIMA Model Residuals," and "Table G Rs: 10*LOG(SPECTRUM) of the regARIMA Model Residuals." If ODS graphics is enabled, the following plots that are associated with diagnostic checking output are produced: the autocorrelation function (ErrorACF) plot of the residuals, the partial autocorrelation function (ErrorPACF) plot of the residuals, the autocorrelation function (SqErrorACF) plot of the squared residuals, a histogram (ResidualHistogram) of the residuals, and a spectral plot (SpectralPlot) of the residuals. See the PLOTS=RESIDUAL option in the PROC X12 statement for further information about controlling the display of plots.

The residual histogram displayed by the X12 procedure shows the distribution of the unstandardized, uncentered regARIMA model residuals; the residual histogram displayed by the U.S. Census Bureau’s X-12-ARIMA seasonal adjustment program displays standardized and mean-centered residuals.

The following options can appear in the CHECK statement:

MAXLAG=value

specifies the number of lags for the residual sample autocorrelation function (ACF) and partial autocorrelation function (PACF). The default is 36 for monthly series and 12 for quarterly series. The minimum value for MAXLAG= is 1.

For the table "Autocorrelation of Squared regARIMA Model Residuals" and the corresponding SqErrorACF plot, the maximum number of lags calculated is 12 for monthly series and 4 for quarterly series. The MAXLAG= option can only reduce the number of lags for this table and plot.

PRINT=ALL | NONE
PRINT=ACF | ACFSQUARED | NORM | PACF
PRINT=RESIDUALOUTLIER | RESIDUALSTATISTICS | SPECRESIDUAL
PRINT=(options)

specifies the diagnostic checking tables to be displayed. If the PRINT= option is not specified, the default is equivalent to specifying PRINT=(ACF ACFSQUARED NORM RESIDUALOUTLIER RESIDUALSTATISTICS SPECRESIDUAL). If PRINT=NONE is specified and no other PRINT= option is specified, then none of the tables that are associated with diagnostic checking are displayed. However, PRINT=NONE has no effect if other PRINT= options are specified in the CHECK statement. PRINT=ALL specifies that all tables related to diagnostic checking be displayed.

PRINT=ACF displays the table titled "Autocorrelation of regARIMA Model Residuals."

PRINT=ACFSQUARED displays the table titled "Autocorrelation of Squared regARIMA Model Residuals."

PRINT=NORM displays the table titled "Normality Statistics for regARIMA Model Residuals". Measures of normality included in this table are skewness, Geary’s a statistic, and kurtosis.

PRINT=PACF displays the table titled "Partial Autocorrelation of regARIMA Model Residuals."

PRINT=RESIDUALOUTLIER or PRINT=RESOUTLIER displays the table "Outliers of the Unstandardized Residuals" if the residuals contain outliers.

PRINT=RESIDUALSTATISTICS or PRINT=RESSTAT displays the table titled "Summary Statistics for the Unstandardized Residuals."