normalize.qspline package:affy R Documentation _N_o_r_m_a_l_i_z_e _a_r_r_a_y_s _D_e_s_c_r_i_p_t_i_o_n: normalizes arrays in an AffyBatch each other or to a set of target intensities _U_s_a_g_e: normalize.AffyBatch.qspline(abatch,type=c("together", "pmonly", "mmonly", "separate"), ...) normalize.qspline(x, target = NULL, samples = NULL, fit.iters = 5, min.offset = 5, spline.method = "natural", smooth = TRUE, spar = 0, p.min = 0, p.max = 1.0, incl.ends = TRUE, converge = FALSE, verbose = TRUE, na.rm = FALSE) _A_r_g_u_m_e_n_t_s: x: a 'data.matrix' of intensities abatch: an 'AffyBatch' target: numerical vector of intensity values to normalize to. (could be the name for one of the celfiles in 'abatch') samples: numerical, the number of quantiles to be used for spline. if (0,1], then it is a sampling rate fit.iters: number of spline interpolations to average min.offset: minimum span between quantiles (rank difference) for the different fit iterations spline.method: specifies the type of spline to be used. Possible values are `"fmm"', `"natural"', and `"periodic"'. smooth: logical, if `TRUE', smoothing splines are used on the quantiles spar: smoothing parameter for `splinefun', typically in (0,1]. p.min: minimum percentile for the first quantile p.max: maximum percentile for the last quantile incl.ends: include the minimum and maximum values from the normalized and target arrays in the fit converge: (currently unimplemented) verbose: logical, if `TRUE' then normalization progress is reported na.rm: logical, if `TRUE' then handle NA values (by ignoring them) type: A string specifying how the normalization should be applied. See details for more. ...: Optional parameters to be passed through _D_e_t_a_i_l_s: This normalization method uses the quantiles from each array and the target to fit a system of cubic splines to normalize the data. The target should be the mean (geometric) or median of each probe but could also be the name of a particular chip in the 'abatch' object. Parameters setting can be of much importance when using this method. The parameter 'fit.iter' is used as a starting point to find a more appropriate value. Unfortunately the algorithm used do not converge in some cases. If this happens, the 'fit.iter' value is used and a warning is thrown. Use of different settings for the parameter 'samples' was reported to give good results. More specifically, for about 200 data points use 'samples = 0.33', for about 2000 data points use 'samples = 0.05', for about 10000 data points use 'samples = 0.02' (thanks to Paul Boutros). The 'type' argument should be one of '"separate","pmonly","mmonly","together"' which indicates whether to normalize only one probe type (PM,MM) or both together or separately. _V_a_l_u_e: a normalized 'AffyBatch'. _A_u_t_h_o_r(_s): Laurent and Workman C. _R_e_f_e_r_e_n_c_e_s: Christopher Workman, Lars Juhl Jensen, Hanne Jarmer, Randy Berka, Laurent Gautier, Henrik Bj{\o}rn Nielsen, Hans-Henrik Saxild, Claus Nielsen, S{\o}ren Brunak, and Steen Knudsen. A new non-linear normal- ization method for reducing variability in dna microarray experiments. Genome Biology, accepted, 2002