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 Test for Dynamic Moving Average Model

Use

The system performs the test for the dynamic moving average (DMA) model as part of automatic model selection . If this test is successful, the system selects the forecast strategies that you assigned to the trend test in Customizing. In the standard case the forecast strategy is “Dynamic Moving Average“. For more information, see the IMG for Advanced Planning and Optimization under Start of the navigation path Supply Chain Planning Next navigation step Service Parts Planning (SPP) Next navigation step Forecasting Next navigation step Configure Automatic Model Selection End of the navigation path .

The test for the dynamic moving average model checks whether there is a large deviation from the average demand for the relevant locations product, which is the case for slow-moving items.

Features

Test

If all of the following conditions are met, the test for the dynamic moving average model is successful.

  • The last forecasted number of order items is greater than your entry in the Threshold for Item in Sporadic Test field in the forecast profile on the Test DMA tab page. You get to the forecast profile on the SAP Easy Access screen under Start of the navigation path Advanced Planning and Optimization Next navigation step Service Parts Planning (SPP) Next navigation step Planning Next navigation step Forecasting End of the navigation path .

  • The last forecasted average demand size per order item is greater than your entry in the Threshold for Demand/Item in Sporadic Test field in the forecast profile on the Test DMA tab page.

  • The number of order items of the previous year is greater than your entry in the Threshold for Item Annual History in Sporadic Test field in the forecast profile on the Test DMA tab page.

  • The quotient from the deviation of the average demand size per order item and the from average demand size per order item is greater than your entry in the Threshold for StdDev/MAD Demand/Item in Sporadic Test field in the forecast profile on the Test DMA tab page.

Negative Test Result

  • If the test was not successful, yet you still use the DMA forecast model for the forecast of the relevant location product, the system uses low limit values to ensure stability. This means that the system proceeds as follows in this case:

    • Instead of your entry in the Threshold for Item in Sporadic Test field, it uses your entry in the Stability Threshold for Item in Sporadic Test field.

    • Instead of your entry in the Threshold for Demand/Item in Sporadic Test field, it uses your entry in the Stability Threshold for Demand/Item in Sporadic Test field.

    • Instead of your entry in the Threshold for Item Annual History in Sporadic Test field, it uses your entry in the Stability Threshold for Item History in Sporadic Test field.

    • Instead of your entry in the Threshold for StdDev/MAD Demand/Item in Sporadic Test field, it uses your entry in the Stability Threshold StdDev/MAD Demand/Item in Sporadic Test field.

  • If you do not use the DMA forecast model for the forecast of the relevant location product, the system check how closely the test failed. The test failed only closely if the following conditions are met:

    • The last forecasted average demand per order item is greater than your entry in the Re-Test of Threshold for Demand/Item in Sporadic Test field.

    • The quotient from the deviation of the average demand size per order item and from the average demand size per order item is greater than your entry in the Re-Test ofThreshold for Demand/Item in Sporadic Test field

      If these conditions are met, the system performs a re-test. To do so, it proceeds as follows:

    • It recalculates the forecast of the average demand size per order item and the quotient described above using the demand history of the last x periods.

      You can define x in the Re-Test of Period Length in Sporadic Test field in the forecast profile on the Test DMA tab page.

    • The system checks whether the results of this calculation are greater than your entries in the Threshold for Demand/Item in Sporadic Test and the Threshold for StdDev/MAD Demand/Item in Sporadic Test fields. If so, the re-test is successful and the system chooses the DMA model as the forecast model for the relevant location product.