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SAP HANA Predictive Analysis Library (PAL)

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Note<br />

F 0 is not defined because there is no estimation for time 0. According to the definition, you can get F 1 = S 0<br />

+ b 0 and so on.<br />

<strong>PAL</strong> calculates the prediction interval to get the idea of likely variation. Assume that the forecast data is<br />

normally distributed. The mean value is S t and the variance is σ 2 . Let U t be the upper bound of prediction<br />

interval for S t and L t be the lower bound. Then they are calculated as follows:<br />

U t = S t + zσ<br />

L t = S t - zσ<br />

Here z is the one-tailed value of a standard normal distribution. It is derived from the input parameters<br />

PREDICTION_CONFIDENCE_1 and PREDICTION_CONFIDENCE_2.<br />

Note<br />

The algorithm is backward compatible. You can still work in the <strong>SAP</strong> <strong>HANA</strong> SPS 11 or older versions where<br />

the prediction interval feature is not available. In that case, only point forecasts are calculated.<br />

Prerequisites<br />

●<br />

●<br />

No missing or null data in the inputs.<br />

The data is numeric, not categorical.<br />

DOUBLESMOOTH<br />

This is a double exponential smoothing function.<br />

Procedure Generation<br />

CALL SYS.AFLLANG_WRAPPER_PROCEDURE_CREATE (‘AFL<strong>PAL</strong>’, ‘DOUBLESMOOTH’,<br />

‘’, '', );<br />

The signature table should contain the following records:<br />

Table 286:<br />

Position Schema Name Table Type Name Parameter Type<br />

1 IN<br />

2 IN<br />

3 OUT<br />

<strong>SAP</strong> <strong>HANA</strong> <strong>Predictive</strong> <strong>Analysis</strong> <strong>Library</strong> (<strong>PAL</strong>)<br />

<strong>PAL</strong> Functions P U B L I C 401

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