Package de.lmu.ifi.dbs.elki.math.linearalgebra.pca.weightfunctions

Weight functions used in weighted PCA via WeightedCovarianceMatrixBuilder

See: Description

Interface Summary

Interface	Description
WeightFunction	WeightFunction interface that allows the use of various distance-based weight functions.

Class Summary

Class	Description
ConstantWeight	Constant Weight function The result is always 1.0
ErfcStddevWeight	Gaussian Error Function Weight function, scaled using stddev.
ErfcWeight	Gaussian Error Function Weight function, scaled such that the result it 0.1 at distance == max erfc(1.1630871536766736 * distance / max) The value of 1.1630871536766736 is erfcinv(0.1), to achieve the intended scaling.
ExponentialStddevWeight	Exponential Weight function, scaled such that the result it 0.1 at distance == max stddev * exp(-.5 * distance/stddev) This is similar to the Gaussian weight function, except distance/stddev is not squared.
ExponentialWeight	Exponential Weight function, scaled such that the result it 0.1 at distance == max exp(-2.3025850929940455 * distance/max) This is similar to the Gaussian weight function, except distance/max is not squared
GaussStddevWeight	Gaussian weight function, scaled using standard deviation \( 1/\sqrt(2\pi) \exp(-\frac{\text{dist}^2}{2\sigma^2}) \)
GaussWeight	Gaussian weight function, scaled such that the result it 0.1 at distance == max, using \( \exp(-2.3025850929940455 \frac{\text{dist}^2}{\max^2}) \).
InverseLinearWeight	Inverse Linear Weight Function.
InverseProportionalStddevWeight	Inverse proportional weight function, scaled using the standard deviation. 1 / (1 + distance/stddev)
InverseProportionalWeight	Inverse proportional weight function, scaled using the maximum. 1 / (1 + distance/max)
LinearWeight	Linear weight function, scaled using the maximum such that it goes from 1.0 to 0.1 1 - 0.9 * (distance/max)
QuadraticStddevWeight	Quadratic weight function, scaled using the standard deviation.
QuadraticWeight	Quadratic weight function, scaled using the maximum to reach 0.1 at that point.

Package de.lmu.ifi.dbs.elki.math.linearalgebra.pca.weightfunctions Description

Weight functions used in weighted PCA via WeightedCovarianceMatrixBuilder