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- for promotions: if you have been able to estimate the effect of a promotion and you have this information you can clean directly the

history.

If you don't know the effect of a promotion but you know the periods on which you had promotions, you can use statistical methods to

estimate them.

- manual correction

This was a very helpful information. Infact, we intend to use an advanced forecasting method, that shall decompose the data into

trend, seasonality. But, for promotion we will have to devise a way.

The trend and seasonality data gets seperated internally through the forecasting heuristic (no link with the SNP heuristic obviously).

Firstly, Model initialization happens where the system determines the necessary model parameters for the chosen forecast strategy.

Based on the model, the basic value, trend value and seasonal value is determined for each historical value during the model

initialization phase. The system is able to do this because it is able to identify patterns in the historical data eg., is there a peakor trough in historic sales repetitively for a particular data set - this can give it the seasonal index, and similarly for trend.

Following this the indices are used for the future periods to forecast. So you really have to do little to seperate the seasonal

and trend values.

Promotion planning is a differend ballgame though.In order to analyse promotion patterns in historic data there is a procedure to be

followed.

On the Promo Planning desktop - Choose the object view Historical analysis from the workspace toolbar and enter here the historic

period for which you wish to decompose promotion - The system applies linear regression to the historical data, thus creating an ex-post forecast, and displays the results in the row Ex-post estimate. The difference between the historical data and the ex-post estimate

is displayed in the Promotion pattern row.

That was really what I was looking out for. You are correct about decomposing data.

May be, I will require your help on promtion segregation as I have never used it. I will try this out and come back to you. In the mean

time, if you could provide more information/steps to seperate out promotion effect, that would be very helpful.

But, all the same, thanks a lot.