Chapter 9: Additional Facilities in PROC X12
9.1 Model Fitting and Forecasting Using PROC X12
9.2 Seasonal Adjustment of US E-Commerce Data Using the Additional Features in PROC X12
9.3 Seasonal Adjustment of the Number of Overnight Stays
9.1 Model Fitting and Forecasting Using PROC X12
Much of the popularity of the X11 method is due to the careful correction for outliers in the series as a part of the adjustment algorithm. In this way, these outliers are prevented from affecting the calculated levels and seasonal factors, and the adjustment is more precise. In general, outliers should appear in the estimated irregular component as clear outliers, and they should not be compensated for by changing the estimated level, trend, and seasonal components. ...
