maotai (version 0.2.6)

nef: Negative Eigenfraction

Description

Negative Eigenfraction (NEF) 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 NEF is far away from 0, it means not Euclidean. The concept of NEF is closely related to the definiteness of a Gram matrix.

Usage

nef(data)

Value

a nonnegative NEF 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 NEF
nef(mydat)