similar to: center or scale before analyzing using pls.pcr

Dear all, I am a newcomer to R. I intend to using R to do stepwise regression and PLS with a data set (a 55x20 matrix, with one dependent and 19 independent variable). Based on the same data set, I have done the same work using SPSS and SAS. However, there is much difference between the results obtained by R and SPSS or SAS. In the case of stepwise, SPSS gave out a model with 4 independent

Dear all, I hope to remove a whole column from a data frame or matrix (> 2000 columns). All value in the column are same. The first thing is to select those columns. For instance, I hope to remove the V3~6 column, for all the value in those colume is zero. V3 V4 V5 V6 V7 V8 V9 V10 1 0 0 0 0 0.000 0.000 0.000 0.000 2 0 0 0 0 0.000 0.000 0.000 0.000 3 0 0 0

Dear all, In one S+ program, I found the following code. if (impres) cat("blah blah blah \n") Would someone here like to tell me what's the counterpart in R to impres in S+? Thanks in advance! Best wishes, Jinsong ===== (Mr.) Jinsong Zhao Ph.D. Candidate School of the Environment Nanjing University 22 Hankou Road, Nanjing 210093 P.R. China E-mail: jinsong_zh at yahoo.com

Hello! I need help to use the package pls.pcr in R. I installed R in an IRIX 6.5, using the version of R 0.64.1 from sgifreeware(I didn't get to install the newest version using make). I need to use the package pls.pcr and when I give the command: # R R : Copyright 1999, The R Development Core Team Version 0.64.1 (May 8, 1999) R is free software and comes with ABSOLUTELY NO

How do you install a package from CRAN ? I want to install pls.pcr, so I have downloaded pls.pcr_0.1.1.tar.gz but when I try to install it using the install package(s) from local zip file(s) option it says : > install.packages(choose.files('',filters=Filters[c('zip','All'),]), .libPaths()[1], CRAN = NULL) Error in file(file, "r") : unable to open connection

Dear list I am using the mvr function of the package pls.pcr to compute PLS resgression using a X matrix of gene expression variables and a Y matrix of medical varaibles. I would like to obtain the R2 (sum of squares captured by the model) and Q2 (proportion of total sum of squares captured in leave-one-out cross validation) of the model. I am not sure if there are specific slots in the

Dear list, I have a question concerning the above mentioned methods in the pls package with respect to the loadings matrix produced by the call. In some work I am doing I have found that the values produced are nearly of the same magnitude but of opposite sign. When I use the example data (sensory) I find this result reproduced. I am prepared to work this through but I have a feeling that

Hi, Currently I have a dataset of 2400*408. And I would like to apply PCR method to study the any correlation between the tests. My current data is in data.frame and I have formed horizontal(1-407) to be the exact data, and (408) to be my results data(Yes and No) I have also binarized these Yes and No to 1 and -1s. However, when I refer to PCR manual on R, the example of yarn.pcr <-

Dear R-users, I would like to process some spectroscopic data with R, and I was hoping some people might have some example code on how to do this. I would like to be able to do the following things: * Detect outlier-spectra -> This can be done by using scoreplot from the pls package * Determine the range of the spectrum to be used -> For this, I should be able to calculate the regression

Hi, I want to calculate PLS package in R. Now I want to calculate R, MSEP, RMSEP and R2 of PLSR and PCR using this. I also add this in library of R. How I can calculate R, MSEP, RMSEP and R2 of PLSR and PCR in R. I s any other method then please also suggest me. Simply I want to calculate these value. Thanking you. -- Nitish Kumar Mishra Junior Research Fellow BIC, IMTECH, Chandigarh, India

Dear R-helpers, Has anybody ever tried to compare pls regression outputs from the pls.pcr R-package developped by Wehrens with outputs from the Unscrambler software developped by CAMO company ? I find very different outputs and wonder if this comes from differences between methods/algorithms SIMPLS (pls.pcr) and PLS1 (Unscrambler). Arnaud ************************* Arnaud DOWKIW Department of

Dear list members, I would like to ask two questions, although the second one must have been answered a thousand times. 1) is there a simple way to estimate the influence of individual variables in PCR and PLS models? What I have in mind is a way to rank the variables according to their influence, using some numerical value of a statistic. 2) what is the proper way to cite a CRAN package? How

I don't know the details of pls (in the pls.pcr package, I assume), but if you use validation="CV", that says you want to use CV to select the best number of components. Then why would you specify ncomp as well? Andy > From: ryszard.czerminski at pharma.novartis.com > > When I try to use ncomp parameter in pls procedure I get > following error: > > >

Dear all, I am trying to my dataframe for the PLS analysis using the PLS package. However I have some trouble generating the correct dataframe. The main problem is how to use one name to represent several columns in the dataframe. The example dataframe in PLS package is called "sensory". I cannot directly read the data file since it's a binary file. If I use

Dear colleagues, May you point me out to the PLS module in R system? I could not find it at all using "PLS" or "partial" as the search keywords. Thank you. Sokratis. ---------------------------------- Sokratis ALIKHANIDI, Ph.D. Department of Knowledge-based Information Engineering Toyohashi University of Technology 1-1 Hibarigaoka, Tempaku-cho, Toyohashi 441, JAPAN TEL:

Dear all, The following is a example that I run and hope to get a linear model. However, I find the lm() can not give correct coefficients for the linear model. I hope it's just my own mistake. Please help. TIA. Regards, Jinsong > x [1] 3.760216 3.997288 3.208872 3.985417 3.265704 3.497505 2.923540 3.193937 [9] 3.102787 3.419574 3.169374 2.928510 3.153821 3.100385 3.768770 3.610583

Hi all, I would like to do some QSAR analysis (quantitative structure activity relationship). I need to use some Partial Least Squares (PLS) regression, but I have not seen this option on the R-project. Is it possible to do this kind of regression on R? thank you in advance best regards, olivier [[alternate HTML version deleted]]

Dear R-users, dear Ron I use pls from the pls.pcr package for classification. Since I need to know which variables are most influential onto the classification performance, what criteria shall I look at: a) B, the array of regression coefficients for a certain model (means a certain number of latent variables) (and: squared or absolute values?) OR b) the weight matrix RR (or R in the De

Hi - I am using pls package for some pcr computations. There is a data set called gasoline. Would someone be able to tell me what command(s) could be used to produce this graph in R? I am not sure where the log(1/R) - Y-axis - are coming from Thanks much Ravi

Dear R-helpers, I have performed a PLS regression with the mvr function from the pls.pcr package an I have 2 questions : 1- do you know if mvr automatically centers the data ? It seems to me that it does so... 2- why in the situation below does the output say that the optimal number of latent variables is 4 ? In my humble opinion, it is 2 because the RMS increases and the R2 decreases when 3 LVs