sft: Selection Frequency Threshold

Description Usage Arguments Value Author(s) Examples

View source: R/sft.R

Description

Determine the selecton frequency threshold of a model at a specified false positive rate

Usage

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sft(x, alpha)

Arguments

x

a randomForest or ranger object

alpha

a false positive rate (ie, 0.01)

Value

a list of two elements

Author(s)

Tom Wilson tpw2@aber.ac.uk

Examples

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library(randomForest)
data(iris)
iris.rf <- randomForest(iris[,-5], iris[,5], forest = TRUE)

# For a false positive rate of 1%
iris.sft <- sft(iris.rf, 0.01)
print(iris.sft)

# To iterate through a range of alpha values

alpha <- c(0.01,0.05, 0.1,0.15,0.2, 0.25)
threshold <- NULL
for(i in seq_along(alpha)){
    threshold[i] <- sft(iris.rf, alpha[i])$sft
}

plot(alpha, threshold, type = 'b')

forestControl documentation built on Nov. 18, 2019, 5:07 p.m.