correlationAnalysis {DramaAnalysis}

Correlation analysis

Description

Calculates correlation of a frequency table with an outcome list according to given method. The function currently only works for pairwise correlation, i.e., two categories. Note that the function keyness() is actually better to do the same thing, and this function should not be used anymore in this fashion.

Usage

correlationAnalysis(text.ft, categories, method = "spearman", culling = 0, ...)

Arguments

text.ft

A matrix, containing words in columns and characters (or plays) in rows. This can be the result of the frequencytable() function.

categories

A factor or numeric vector that represents a list of categories.

method

The correlation method, passed on to cor()

culling

An integer. Words that appear in less items are removed. Defaults to 0 which doesn't remove anything.

...

Arguments passed to cor()

Value

The function returns a data.frame with three columns: The word, it's correlation score, and the category it is correlated to. The latter is mainly for an easier use of the results.

Examples

data(rksp.0)
ft <- frequencytable(rksp.0, byCharacter=TRUE)
g <- factor(c("m","m","m","m","f","m","m","m","f","m","m","f","m"))
rksp.0.cor <- correlationAnalysis(ft, g)

# to pre-filter by the total frequency of a word
ft <- frequencytable(rksp.0, byCharacter=TRUE)
ft <- ft[,colSums(ft) > 5]
correlationAnalysis(ft, g)