Automatic Model Selection

[lalit_behere]

Hi,

We are using Automatic Model Selection ( 56 ) for forecast calculation.

I get error message :

" Not enough values for auto. model selection; currently: 20, required 24."

I have defined History Horizon < 24.

Is it necessary to have history horizon of at least 2 years ?

Regards

Lalit

[satish_waghmare3 · Accepted solution]

Hello Lalit

I agree with Mukesh's response.

As all the Univariate models are basically Time Series models.  Time series models use patterns from the past to try and predict the future(extrapolation). These models required number of periods for forecast model initialization and to identify the data pattern, and so it has an impact on history horizon.

Following is how I have understood model initialization period required by forecast models -

Constant Model requires ...1 Period...because it has to just use that one period and then extrapolate into future.

Trend Model requires - 3 Periods...to know whether trend is increasing(upward) or decreasing(downward) minimum 3 periods are essential.

Seasonal - 1 complete season...as this will tell the system how the demand is shaping up, which all months it rises or contracts and which all months it flattens..

With same logic for Trend + Seasonal model requires....1 complete Season and 3 Periods.

Here is the SAP Help link on this topic

Model Initialization - Forecasting - SAP Library

Hope this will help.

Thank you

Satish Waghmare

[satish_waghmare3]

Hello Lalit

I would like to share one more link which provides details about How Automatic Model Selection Procedure 1 works and its model initialization.  Point#2 from 'Activities' section from below link will give you some good insight on Model initialization with Auto Model.

Automatic Model Selection Procedure 1 - Creating a Master Forecast Profile - SAP Library

Please check

Thank you

Satish Waghmare

[Former Member]

Hi Lalit,

You need at least 2 seasonal cycles and 3 periods as historical values to initiate the model. However if less are available the procedure will run, but models that require more initialization periods, such as seasonal trend, are not used.

Check the number of periods per seasonal cycle defined in the univariate profile. It seems there are 12 periods in the profile. It mean you need at least 2 seasonal cycles(24 periods) to initiate the model.

Regards,

Mukesh