Outlier Correction 

Use

An outlier is an historical value that lies outside a range that is expected. Outliers can falsify the forecast results. This function enables you to correct the outliers.

Prerequisites

It is not possible to use outlier correction with the median forecast method (method 36).

Features

SAP has made considerable changes to the algorithms for outlier correction in Release SCM 4.1.

There are two methods:

Ex-Post Method

In this method the system uses the ex-post forecast to determine a tolerance lane. If a historical value lies outside this tolerance lane, the system views it as an outlier and corrects it.

For more information, see Outlier Correction with the Ex-Post Method.

Median Method

The system uses the median method to determine the ex-post forecast values for the basic value, trend value, and the seasonal index. It can thus calculate an expected value for each historical period

 

The tolerance lane is calculated as Sigma * Expected value.

For more information, see Outlier Correction with the Median Method.