Here, j is the smallest integer with max ( | v i |<1 ).

Example 3.6 (Decimal scaling). The recorded values of Sweden Economy (Table 2.8) vary from 102 to 192. The maximum absolute value pertaining to Sweden is 192. In order to normalize by decimal scaling, each value is divided by 1,000 (i.e., j =3) and by doing so 102 normalizes to 0.102, and 192 normalizes to 0.192.

It is possible to see cases when normalization can alter the original data slightly, when using z-score normalization or decimal scaling, particularly. At the same time, it is required to save the normalization parameters (e.g., the mean and standard deviation if one uses z-score normalization). If this is done, then future data can be normalized uniformly.

3.8Classification ...

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