SOE {loe}R Documentation

Soft Ordinal Embedding (SOE)

Description

Performs SOE for a given part of ordinal informaiton.

Usage

SOE(CM, N, p = 2, c = 0.1, maxit = 1000, report = 100, iniX = "rand",rnd=10000)

Arguments

CM

A matrix whose rows represent ordinal information: A row vector (i,j,k,l) means xi_{ij} < xi_{kl}, where xi_{ij} is a dissimilarity between object i and object j. If the number of given ordinal comparisons is more than 100000, then SOE randomly chooses rnd ordinal comarisons from given comparisons.

N

The number of objects.

p

The number of dimensions.

c

Scale parameter which only takes strictly positive value.

maxit

Maximum number of iteretions.

report

The frequency of reports. Defaults to every 100 iterations.

iniX

Matrix with starting values for embedding (optional).

rnd

The number of ordinal comarisons which are randomly chosen from given ordinal comparisons CM. rnd is used only if the number of given ordinal comparisons is more than 100000.

Value

SOE returns a list with components:

X

The best corrdinate matrix with p columns whose rows give the coordinates of objects.

str

The value of the stress function of SOE corresponding to X.

Author(s)

Yoshikazu Terada

Examples

library(MASS)
data(eurodist)
OIF <- get.order(as.matrix(eurodist))
sid <- sample(1:nrow(OIF))
POI <- OIF[sid[1:1000],]
result <- SOE(CM=POI, N=nrow(as.matrix(eurodist)),p=2, c=0.1,maxit =1000,report=100)
plot(result$X,type="n",xlab="Dim. 1", ylab="Dim. 2")
text(result$X,rownames(as.matrix(eurodist)),cex=1)

[Package loe version 1.1 Index]