IsingSampler (version 0.2.3)

LinTransform: Transform parameters for linear transformations on response catagories

Description

This function is mainly used to translate parameters estimated with response options set to 0 and 1 to a model in which the response options are -1 and 1, but can be used for any linear transformation of response options.

Usage

LinTransform(graph, thresholds, from = c(0L, 1L), to = c(-1L, 1L), a, b)

Arguments

graph

A matrix containing an Ising graph

thresholds

A vector containing thresholds

from

The original response encoding

to

The response encoding to transform to

a

The slope of the transformation. Overwrites to.

b

The intercept of the transformation. Overwrites to.

Author

Sacha Epskamp <[e-mail]>

Examples

N <- 4 # Number of nodes

# Ising parameters:
Graph <- matrix(sample(0:1,N^2,TRUE,prob = c(0.7, 0.3)),N,N) * rnorm(N^2)
Graph <- pmax(Graph,t(Graph)) / N
diag(Graph) <- 0
Thresh <- -(rnorm(N)^2)
Beta <- 1

p1 <- IsingLikelihood(Graph, Thresh, Beta, c(0,1))

a <- 2
b <- -1

# p2 <- IsingLikelihood(Graph/(a^2), Thresh/a - (b*rowSums(Graph))/a^2, Beta, c(-1,1))

p2 <- IsingLikelihood(LinTransform(Graph,Thresh)$graph, 
                      LinTransform(Graph,Thresh)$thresholds , 
                      Beta, c(-1,1))
LinTransform

round(cbind(p1[,1],p2[,1]),5)

plot(p1[,1],p2[,1])
abline(0,1)