similar to: New R-SIG for Discrete Choice Modelling

Hello, I would like to know if there is any function in R which allows to make designs of experiments for Choice-Based Conjoint studies ? I have already checked the topic on " design of experiments with R " and looked at the different libraries. I tried to make my design with the "optFedorov" function but I haven't found how it can allow to have balanced design (with the

Hello everyone, I am new to this list and the R-Project, so I hope my question is not trivial or has been answered before. I searched the FAQs and the mailing list archives and I could not find anything about Conjoint Analysis. I am especially interested in Choice-based Conjoint, resp. discrete choice models. Is there a function / module that handles this issue? Or can the multinomial logit

A package I have written makes considerable use of external C code. There appear to be no problems building a Windows binary with the GNU C compiler, but now I would like to make the package available for other platforms. A stringent check of the code with the gcc options '-Wall -pedantic' flags many nested functions and variable-length arrays that are not allowed in ISO C. Is it

Afternoon everyone, I''ve spent the last week or so looking at all the experimental design packages I can find in R. AlgDesign, design.conf and BHH2 being the best one I could find. Unfortunately none of these do a particularly good job for complex designs, in particular for conjoint or discrete choice. (or perhaps they do, and I can''t make them work correctly)

Hello Prof. Harrell and dear R-help mailing list, I wish to perform a non-parametric repeated measures anova. If what I read online is true, this could be achieved using a mixed Ordinal Regression model (a.k.a: Proportional Odds Model). I found two packages that seems relevant, but couldn't find any vignette on the subject: http://cran.r-project.org/web/packages/repolr/

Dear R users I would like to simulate underdispersed Poisson and binomial distributions somehow. I know you can do this for overdispersed counterparts - using rnbinom() for Poisson and rbetabinom() for binomial. Could anyone share functions to do this? Or please share some tips for modifying existing functions to achieve this. Thank you very much for your help and time Shinichi

L.S. We would like to generate fractional design for a conjoint analysis. For example we would like to reduce 2x2x2x2x3 --> 12-16 profiles. We tried the R-package "conjoint" and we found an article which describes how to make fractional design for these kinds of studies with Algdesign: http://tolstoy.newcastle.edu.au/R/e10/help/att-8876/DCE_with_R.pdf However, the generated

## Question1: How to define IV with interaction alone, without main effects? ## Question2: Should Type III ANOVA in package car be independent of the factor level order? ## data from http://www.otago.ac.nz/sas/stat/chap30/sect52.htm drug <- c(t(t(rep(1,3)))%*%t(1:4)); disease <- c(t(t(1:3)) %*% t(rep(1,4))); y <- t(matrix(c( 42 ,44 ,36 ,13 ,19 ,22 ,33 ,NA ,26 ,NA ,33 ,21 ,31 ,-3 ,NA

Hi, I am trying to connect points on a graph that originate from *different columns of data*. For each sample I have minimum and maximum data points and I would like to draw a line connecting these in order to visualize the spread, as well as where each sample is in relation to the x-axis. So far I can generate the points, but the only lines I have been able to make join all the minimum values

Dear All I'm logging the stdout and stderr of an R program into two separate files (stderr.txt and stdout.txt) using sink() I would like to append extra information such as "date", "memory usage" etc to every line of output that goes to stdout or stderr. For example > cat("hello \n") should give output that looks something like: "hello --- Thu Jun 19

I have just used the RAqua.pkg to install R, and it doesn't work! I have Mac OS X 10.3, and the old version of R works OK, but the .pkg thing installed, and then when I double-click on the "StartR" application nothing happens. Nothing at all, no little icon bobbing up and down in the dock, just nothing. What have I done wrong? I didn't have to install the other packages

Hi, I'm trying to build a thesaurus that will sensible values for rare words. I suspect the best algorithm to use is k-means although I'm not sure about that -- I would have preferred a k dimensional space with a binary cluster in each dimension so a word can belong to 0..k clusters, but I digress... I can measure the strength of correlation between words fairly easily by counting

Hi I came across this strange bug the other day, I'm not sure how to solve it and I wonder if anyone can even replicate it. Using OS Ubuntu 7.10 Step 1) Make an R package using the package.skeleton() command with only these two functions: error <- function(){ cmd <- paste(" -a ",1," -a ",1," -a ",1, " -a ",1," -a

Hi I have used fa() to perform a factor analysis of a psychological battery which is thought to have 11 factors. I can identify which factors the loadings relate to easily enough because I can see which items are loading onto each of the columns in the $loading output. However, how can I identify which items or loadings are being used to create each of the columns in the $scores output? I have

Hi I'm new to R and would like some help with a couple of problems. I suspect the solutions are quite simple. I have a data.frame (data) with 40 variables and 5238 observations created from ~150 text files using read.table. I would like to change some of the entries within two different columns. Firstly, in the Group column I have groups A and B, I would like to select all As and change

Hola, tengo que leer más de 2000 ficheros en un programa largo de estimación sobre imágenes médicas, con una estructura como ésta: desde "IM-0005-0001.dcm" hasta "IM-0005-2021.dcm" Si hago esto: ui <- NULL for (i in 1:8){ ui[i] <- paste("IM-0005-", i,".dcm", sep="") } ui Obtendría: [1] "IM-0005-1.dcm"

Hello all, I am trying to apply a conjoint analysis in order to determine the best profile that captures the most preferred combination of levels of given categorical factors. For this a set of factors is given and initially a fractional factorial design has to be produced as a subset of all possible factor levels combinations, sufficient to estimate the main effects utilities. Then the

We've recently had a thread on beginners and FAQs and the like. I decided that it might be a good idea to offer a short list of on-line help pages that beginners should read. Goals: - the list short be short (I think mine is too long) - many of the commonest questions should find answers there (fairish) - I should have found the pages helpful myself (no question about that) - it's a

Pls advise how I can use R in conjoint analysis?? regds Faisal Afzal Siddiqui Karachi, Pakistan ____________________________________________________________________________________ Looking for last minute shopping deals?

I've been trying for the past 3 weeks to use R (much better than Matlab but I am very bad with computers so I am very new to all of this) and know how to input the data (hey, it's a start!) but every time I type in the following: dcm <- decompose(information) I get the following error message: Error in decompose(information) : time series has no or less than 3 periods Could you