PredictVariance

Returns the variance of a specified column.

Syntax

PredictVariance(<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, PredictVariance returns 0 because the variance cannot be calculated from discrete values.

Examples

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

SELECT
  [Bike Buyer],
  PredictVariance([Bike Buyer]) AS [Variance],
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

Reference

Data Mining Extensions (DMX) Function Reference
Functions (DMX)
Mapping Functions to Query Types (DMX)

Help and Information

Getting SQL Server 2005 Assistance