phicoef: Calculate the "phi coefficient" between two binary variables

Description Usage Arguments Value Author(s) References Examples

View source: R/phicoef.R

Description

The phicoef function calculates the "phi coefficient" between two binary variables.

Usage

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phicoef(x, y=NULL)

Arguments

x, y

Two logical vectors of the same length. If y is not supplied, x must be a 2x2 integer matrix (or an integer vector of length 4) representing the contingency table of two binary variables.

Value

The "phi coefficient" between the two binary variables. This is a single numeric value ranging from -1 to +1.

Author(s)

H. Pagès

References

http://en.wikipedia.org/wiki/Phi_coefficient

Examples

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set.seed(33)
x <- sample(c(TRUE, FALSE), 100, replace=TRUE)
y <- sample(c(TRUE, FALSE), 100, replace=TRUE)
phicoef(x, y)
phicoef(rep(x, 10), c(rep(x, 9), y))

stopifnot(phicoef(table(x, y)) == phicoef(x, y))
stopifnot(phicoef(y, x) == phicoef(x, y))
stopifnot(phicoef(x, !y) == - phicoef(x, y))
stopifnot(phicoef(x, x) == 1)

Example output

Loading required package: stats4
Loading required package: BiocGenerics
Loading required package: parallel

Attaching package: 'BiocGenerics'

The following objects are masked from 'package:parallel':

    clusterApply, clusterApplyLB, clusterCall, clusterEvalQ,
    clusterExport, clusterMap, parApply, parCapply, parLapply,
    parLapplyLB, parRapply, parSapply, parSapplyLB

The following objects are masked from 'package:stats':

    IQR, mad, xtabs

The following objects are masked from 'package:base':

    Filter, Find, Map, Position, Reduce, anyDuplicated, append,
    as.data.frame, cbind, colnames, do.call, duplicated, eval, evalq,
    get, grep, grepl, intersect, is.unsorted, lapply, lengths, mapply,
    match, mget, order, paste, pmax, pmax.int, pmin, pmin.int, rank,
    rbind, rownames, sapply, setdiff, sort, table, tapply, union,
    unique, unsplit, which, which.max, which.min

Loading required package: S4Vectors

Attaching package: 'S4Vectors'

The following objects are masked from 'package:base':

    colMeans, colSums, expand.grid, rowMeans, rowSums

Loading required package: IRanges
Loading required package: GenomeInfoDb
[1] -0.09785447
[1] 0.8899124

GenomicRanges documentation built on Nov. 17, 2017, 11:35 a.m.