heter.QRank: Heterogeneity index for "QRank"

In QRank: A Novel Quantile Regression Approach for eQTL Discovery

Description

Calculate the heterogeneity index of quantile regression coefficients at multiple quantile levels. It measures the variation of the quantile coefficients across quantile levels.

heterogeneity=log(sd(β)/abs(mean(β)))

where β is the vector of quantile regression coefficients at multiple quantile levels.

Usage

heter.QRank(object, newtaus=NULL)

Arguments

object	Object returned from "QRank"
newtaus	a vector of quantile levels based on which heterogeneity index are calculated. Default is NULL, in which case the quantile levels inherited from "QRank" will be used.

Value

heterogeneity index

one hetergeneity index

See Also

QRank

Examples

# continuted from "QRank"

taus=c( 0.25, 0.5, 0.75)
q = QRank(gene=y, snp=x, cov=z, tau=taus)  
heter.QRank(q) # default uses taus inherited from "QRank"
# - output
#Heterogeneity index:
#[1] 2.474184
heter.QRank(q,newtaus = 1:9/10) # calculate based on new taus values
# - output
#Heterogeneity index:
#[1] 2.69242

QRank documentation built on May 1, 2019, 10:55 p.m.