Data cleansing can be turned on and off by changing the Advance Server Settings of the Demand Plan Server. The change is done by changing the ForecastModels\DataCleansing\CleansingMethod when set to 0, and no data cleaning is preformed when set to 1 then the standard derivation method is used for data cleansing.
The standard derivation cleansing method works like this:
1. Find the standard derivation of the parts historical demand.
2. Check if some periods are outside 3 standard derivations, if a period are outside set the period = to 3 standard derivations.
The same check is preformed when calculating the error message MSR if the ForecastModels\DataCleansing\MSRCleansingMethod is set to 1. Then the 3 sigma upper/lower band number is used as history in periods where the real demand is outside these intervals for calculating MSR.
| 100 | 106 | 110 | 250 | 113 | 107 | 111 | 110 | 112 | 99 | 109 | 111 |
The following demand gives an upper limit of 243 and a lower limit of = 0 (-3,8). That means that any value above 243 will be changed, on the lower side all values will be allowed since the lower limit is negative and we cannot have negative demand.
We see that period 4 is to high, this period will be adjusted down to 243. Note that if you have changed the adjusted demand manually a little lock will appear and the value will not be altered.
So the final history will be:
| 100 | 106 | 110 | 243 | 113 | 107 | 111 | 110 | 112 | 99 | 109 | 111 |
This is the historical demand that the forecast model calculations will be based upon.
Note that Data Cleansing is not done when you have selected the following forecast models: