normalize.quantiles.target: Quantile Normalization using a specified target distribution...

In preprocessCore: A collection of pre-processing functions

Description

Using a normalization based upon quantiles, these function normalizes the columns of a matrix based upon a specified normalization distribution

Usage

  normalize.quantiles.use.target(x,target,copy=TRUE,subset=NULL)
  normalize.quantiles.determine.target(x,target.length=NULL,subset=NULL)

Arguments

x	A matrix of intensities where each column corresponds to a chip and each row is a probe.
copy	Make a copy of matrix before normalizing. Usually safer to work with a copy
target	A vector containing datapoints from the distribution to be normalized to
target.length	number of datapoints to return in target distribution vector. If NULL then this will be taken to be equal to the number of rows in the matrix.
subset	A logical variable indexing whether corresponding row should be used in reference distribution determination

Details

This method is based upon the concept of a quantile-quantile plot extended to n dimensions. No special allowances are made for outliers. If you make use of quantile normalization either through rma or expresso please cite Bolstad et al, Bioinformatics (2003).

These functions will handle missing data (ie NA values), based on the assumption that the data is missing at random.

Value

From normalize.quantiles.use.target a normalized matrix.

Author(s)

Ben Bolstad, [e-mail]

References

Bolstad, B (2001) Probe Level Quantile Normalization of High Density Oligonucleotide Array Data. Unpublished manuscript http://bmbolstad.com/stuff/qnorm.pdf

Bolstad, B. M., Irizarry R. A., Astrand, M, and Speed, T. P. (2003) A Comparison of Normalization Methods for High Density Oligonucleotide Array Data Based on Bias and Variance. Bioinformatics 19(2) ,pp 185-193. http://bmbolstad.com/misc/normalize/normalize.html

See Also

normalize.quantiles

preprocessCore documentation built on Jan. 10, 2021, 2:01 a.m.