Select the scheme that normalizes the data for the selected attribute, and enter any necessary values. Note the restrictions on scheme values.
To view a histogram of the values, click Histogram.
Specify the normalization transformation for the attribute by specifying a Formula. Click Select a transformation, and click the formula to use. The available formulas are:
(x - MIN(x))/(MAX(x) - MIN(x))*(new max - new min) + new min
, Min-Max Normalization(x - MEAN(x))/SQRT(VARIANCE(x))
, Z-Score Normalization(x/MAX(ABS(MIN(x)), ABS(MAX(x)))
, Linear Scale (normalizes sparse data to a value between -1 and +1)Note: The functions (MAX, MIN, VARIANCE, etc.) in the formulas use the notation of the SQL functions; for definitions, see Numeric Functions in Schemes.
Click Histogram to view a histogram of the attribute for which you are defining a normalization scheme.
After you select a formula, click Refresh. To illustrate the effect of the transformation, new statistics are displayed and compared with the original statistics.
To display the effect of the formula, click Refresh.
When you are satisfied with the scheme definition, click OK to apply the scheme. You can click Cancel to cancel the scheme selection.
The selected formula appears in the Scheme column.
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