maotai (version 0.2.6)

nem: Negative Eigenvalue Magnitude

Description

Negative Eigenvalue Magnitude (NEM) is a measure of distortion for the data whether they are lying in Euclidean manner or not. When the value is exactly 0, it means the data is Euclidean. On the other hand, when NEM is far away from 0, it means not Euclidean. The concept of NEM is closely related to the definiteness of a Gram matrix.

Usage

nem(data)

Value

a nonnegative NEM value.

Arguments

data

an \((n\times p)\) matrix whose rows are observations.

References

pekalska_noneuclidean_2006maotai

Examples

## use simple example of iris dataset 
data(iris) 
mydat = as.matrix(iris[,1:4])

## calculate NEM
nem(mydat)