diffMeanVar (version 0.0.6)

BFtest: Test for equality of variance based on Brown and Forsythe's test

Description

Test for equality of variance based on Brown and Forsythe's test.

Usage

BFtest(value, group)

Arguments

value

numeric. Measurements to be compared between two groups.

group

numeric. Subject's group membership. Must be binary (i.e., taking values 0 or 1).

Value

A list with 2 elements:

stat

test statistic value

pval

pvalue of the score test

References

Brown MB and Forsythe AB (1974) Robust Tests for Equality of Variances. Journal of the American Statistical Association, 69, 364-367.

Examples

# NOT RUN {
    # generate simulated data set from t distribution
    set.seed(1234567)
    es.sim = genSimData.tDistr(nCpGs = 100, nCases = 20, nControls = 20,
      df0 = 10, ncp0 = 0, df1 = 6, ncp1 = 2.393, testPara = "var",
      eps = 1.0e-3, applier = lapply) 
    print(es.sim)
    print(exprs(es.sim)[1:2,1:3])

    # do AW score test for the first probe
    dat = exprs(es.sim)
    pDat = pData(es.sim)
    print(pDat[1:2,])

    res = BFtest(value = dat[1,], group = pDat$memSubj)
    print(names(res))
    print(res)
# }