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PredictStdev (DMX)

  • Άρθρο

Applies to: SQL Server Analysis Services

Returns the predicted standard deviation for the specified column.

Syntax

  
PredictStdev(<scalar column reference>)

Applies To

A scalar column.

Return Type

A scalar value of the type that is specified by <scalar column reference>.

Remarks

If the column reference is discrete, PredictStdev returns 0 because the standard deviation cannot be calculated from discrete values.

Examples

The following example uses a natural prediction join to determine whether an individual is likely to be a bike buyer based on the TM Decision Tree mining model, and also determines the standard deviation for the prediction.

SELECT  
  [Bike Buyer],  
  PredictStdev([Bike Buyer]) AS [Standard Deviation]  
FROM  
  [TM Decision Tree]  
NATURAL PREDICTION JOIN  
(SELECT 28 AS [Age],  
  '2-5 Miles' AS [Commute Distance],  
  'Graduate Degree' AS [Education],  
  0 AS [Number Cars Owned],  
  0 AS [Number Children At Home]) AS t

See Also

Data Mining Extensions (DMX) Function Reference
Functions (DMX)
General Prediction Functions (DMX)