Scalers

We offer a catalogue of well-known scalers for use across algorithms.

The catalogue of scalers

We have these scalers available (all case-insensitive):

Scaler Identifier

Center

Center

Log scaler

Log

Max scaler

Max

Mean scaler

Mean

Min-max scaler

MinMax

Standard score

StdScore

L1 norm

L1Norm

L2 norm

L2Norm

Details

The scalers are well understood, and are documented below.

Center

Transforms all properties by subtracting the mean.

p minus average value of p

The average value is reported as a statistic when this scaler is used.

Log scaler

Transforms all property values using the natural logarithm. C denotes a configurable constant offset, which can be used to avoid negative values or zeros in the value space, as their logarithms are not finite values.

scaled p equals natural logarithm of p

Max scaler

Scales all property values into the range [-1, 1] where the maximum absolute value(s) get the scaled value 1, according to this formula:

scaled p equals p divided by the maximum of absolute p

The maximum absolute value is reported as a statistic when this scaler is used.

Mean scaler

Scales all property values into the range [-1, 1] where the average value(s) get the scaled value 0.

scaled p equals p minus average of p divided by maximum of p minus minimum of p

The minimum, maximum and average values are reported as statistics when this scaler is used.

Min-max scaler

Scales all property values into the range [0, 1] where the minimum value(s) get the scaled value 0 and the maximum value(s) get the scaled value 1, according to this formula:

scaled p equals p minus minimum of p divided by maximum of p minus minimum of p

The minimum and maximum values are reported as statistics when this scaler is used.

Standard Score

Scales all property values using the Standard Score (Wikipedia).

scaled p equals p minus average of p divided by standard deviation of p

The average value and standard deviation are reported as statistics when this scaler is used.

L1 Norm

Scales all property values using the L1 Norm (Wikipedia), also known as Manhattan norm.

scaled p equals p divided by l1 norm of p

The L1 norm is useful for getting a discrete probability distribution of properties whose values are non-negative, such as PageRank or ArticleRank.

L2 Norm

Scales all property values using the L2 Norm (Wikipedia), also known as Euclidean norm.

scaled p equals p divided by l2 norm of p

The sum of squares of scaled values will equal 1 when the L2 norm is used.