normalize.quantiles.in.blocks package:affyPLM R Documentation _Q_u_a_n_t_i_l_e _N_o_r_m_a_l_i_z_a_t_i_o_n _c_a_r_r_i_e_d _o_u_t _s_e_p_a_r_a_t_e_l_y _w_i_t_h_i_n _b_l_o_c_k_s _o_f _r_o_w_s _D_e_s_c_r_i_p_t_i_o_n: Using a normalization based upon quantiles this function normalizes the columns of a matrix such that different subsets of rows get normalized together. _U_s_a_g_e: normalize.quantiles.in.blocks(x,blocks,copy=TRUE) _A_r_g_u_m_e_n_t_s: 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 blocks: A vector giving block membership for each each row _D_e_t_a_i_l_s: 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). _V_a_l_u_e: From 'normalize.quantiles.use.target' a normalized 'matrix'. _A_u_t_h_o_r(_s): Ben Bolstad, bmb@bmbolstad.com _R_e_f_e_r_e_n_c_e_s: Bolstad, B (2001) _Probe Level Quantile Normalization of High Density Oligonucleotide Array Data_. Unpublished manuscript Bolstad, B. M., Irizarry R. A., Astrand, M, and Speed, T. P. (2003) _A Comparison of Normalization Methods for High Density Oligonucleotide Array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. _S_e_e _A_l_s_o: 'normalize' _E_x_a_m_p_l_e_s: ### setup the data blocks <- c(rep(1,5),rep(2,5),rep(3,5)) par(mfrow=c(3,2)) x <- matrix(c(rexp(5,0.05),rnorm(5),rnorm(5,10))) boxplot(x ~ blocks) y <- matrix(c(-rexp(5,0.05),rnorm(5,10),rnorm(5))) boxplot(y ~ blocks) pre.norm <- cbind(x,y) ### the in.blocks version post.norm <- normalize.quantiles.in.blocks(pre.norm,blocks) boxplot(post.norm[,1] ~ blocks) boxplot(post.norm[,2] ~ blocks) ### the usual version post.norm <- normalize.quantiles(pre.norm) boxplot(post.norm[,1] ~ blocks) boxplot(post.norm[,2] ~ blocks)