varianceBasedfilter: To filter genes according to expression variability

Description Usage Arguments Details Value Author(s) References Examples

Description

Those genes not significantly more variable than the median gene are filtered out.

Usage

1

Arguments

exprs

a data frame or matrix with rows for variables (genes) and columns for samples.

p

the probability cut-off of the chi-squared model of the gene-specific variance-like statistics.

Details

This is an approximate test of the hypothesis that gene has the same variance as the median variance. A statistical significance criterion based on the variance can be used. If the significance criterion is chosen, then the variance of the log-values for each gene is compared to the median of all the variances. The quantity for each gene compared to a percentile of the chi-square distribution with n-1 degrees of freedom. Those genes not significantly more variable than the median gene are filtered out [BRB-ArrayTools Version 3.7].

Value

A data frame or matrix with a reduced number of rows.

Author(s)

Jing Yang

References

Dr. Richard Simon & Amy Peng Lam, BRB-ArrayTools (v3.7) User's Manual: 'Log expression variation filter'.

Examples

1
2

DSviaDRM documentation built on May 2, 2019, 5:54 a.m.