popsom (version 4.0.1)

map.accuracy: Estimated Topographical Accuracy

Description

Evaluate the topological quality of a SOM using the estimated topographical accuracy.

Usage

map.accuracy(map,k=50,conf.int = 0.95,verb=FALSE,interval=TRUE)

Arguments

map

an object of type 'map'.

k

number of samples to use in the computation of the estimated topographical accuracy (default=50)

conf.int

the confidence interval of the estimated topographical accuracy (default 95 percent).

verb

a switch controlling the structure of the output value (default=FALSE)

interval

a switch that controls whether the confidence interval is computed (default=TRUE)

Value

1) The value of the estimated topographical accuracy. 2) The low value of the confidence interval and the high value of the confidence interval 'conf.int' if interval=TRUE. 3) If verb=TRUE then map.accuracy will return a vector with the accuracies of the individual k samples.

References

"SOM Quality Measures: A Statistical Approach," Lutz Hamel, WSOM16, 2016'.

Examples

data(iris)

## set data frame and labels
df <- subset(iris,select=-Species)
labels <- subset(iris,select=Species)

## build a map
m <- map.build(df, labels, xdim=15, ydim=10, train=1000)

## display estimated topographical accuracy of the map
map.accuracy(m)