similar to: R and clinical studies

Dear R-users, I haven?t found rules for logical operators. I need to select data according the following rule: Condition A & (Condition B | Condition C) How should I write it?? Is Condition A & Condition B | Condition C correct or will R execute (Condition A & Condition B) | Condition C ? Thanks for your help. Delphine Fontaine Delphine Fontaine Statistician Statistics

Dear R-users, I would like to create a new data frame composed of 2 columns of another data frame. But it does not give me what I want... > casesCNST[1:10,] case X1 X2 X3 X4 expected 1 A1 0 0 0 0 E 2 A2 0 0 0 1 C 3 A3 0 0 0 2 C 4 A4 0 0 0 3 C 5 A5 0 0 0 4 C 6 A6 0 0 1 0 C 7 A7 0 0 1 1 C 8

Following up to some extent on Friday's discussion regarding the 'validation' of R, could I ask the list group's opinion on possible advantages of R over Splus from a pharma/devices perspective? I wish to exclude the obvious price difference, which doesn’t seem to carry as much weight as I would have thought. Besides, I have noticed many former Splus users gravitating towards R,

Hello Everyone,   I’m a SAS user who has recently become interested in sequential clinical trials designs. I’ve discovered that the SAS based approaches for these designs are either too costly or are “experimental.” So now I’m looking for alternative software. Two programs that seem promising are SPLUS Seqtrial and R.   I recently obtained a 30 day trial for the SPLUS Seqtrial add-on and have

Dear all, I''d like to ask help on R code to get the same results as the following Splus code: >indata<-importData("/home/data_new.csv") >indata[1:5,4] [1] 0930 1601 1006 1032 1020 I tried the following R code: > indata<-read.csv("/home/data_new.csv") > indata[1:5,4] [1] 930 1601 1006 1032 1020 I''d like the first

I made an ANOVA with repeated mesures (aov(Mesure~Distance*Genre*Correct+Error(Sujet/(Distance*Genre*Correct)), data)) and I would like to extract the pvalues. The output is: ----------------------------------------------------------- Error: Sujet Df Sum Sq Mean Sq F value Pr(>F) Residuals 21 97.082 4.623 Error: Sujet:Distance Df Sum Sq Mean Sq F value Pr(>F) Distance

I would like to use R for submissions to FDA/CDRH (the medical device company I work for currently uses only SAS). Previous postings to the list regarding R and 21 CFR 11 compliance have been very helpful. However, reluctance to using open source software for statistical analyses and reporting remains high here at my company. Has anyone used R for an official submission to FDA/CDRH? It would

Dear Sweave-users, I want to print listing using sweave. Because my tables are very big, I use the longtable option. But, is it possible to recall the first line of the table (e.g the colnames line) on each new page ? Thanks for your help. Delphine

I am one of only 5 or 6 people in my organization making the effort to include R/Splus as an analysis tool in everyday work - the rest of my colleagues use SAS exclusively. Today, one of them made the assertion that he believes the numerical algorithms in SAS are superior to those in Splus and R -- ie, optimization routines are faster in SAS, the SAS Institute has teams of excellent numerical

Dear R-users, The sasxport.get function (from the Hmisc package) automatically defines the class of imported variables. I have noticed that the class of theoretically numeric variables is simply "labelled", although character variables might end up been defined as "labelled" "Date" or "labelled" "factor". Is there a way to tell sasxport.get to

Hi, I started playing around with a function for using StatTransfer (version 10) for importing data. This started as a simple task but it's not working and so now I'm very frustrated. I'm using R version 2.13 on Windows 7. The function, called fn.importData, is: function(file = NULL, type = NULL){ ## ## create statTransfer command file -

Hi, I would like to simulate data with a binary outcome and a set of predictors that are correlated. I want to be able to fix the number of event (Y=1) vs. non-event (Y=0). Thus, I fix this and then simulate the predictors. I have 2 questions: 1. When the predictors are continuous, I can use mvrnorm(). However, if I have continuous, ordinal and binary predictors, I'm not sure how to simulate

Dear all, There have been a variety of discussions on the R list regarding the use of R in clinical trials. The following post from the STATA list provides an interesting opinion regarding why SAS remains so popular in this arena: http://www.stata.com/statalist/archive/2008-01/msg00098.html Regards, -Cody Hamilton

I've got a data frame having numerical data by zip code: ZIP DATA 94111 12135.545 93105 321354.65654 94111 545.555 94706 558858.66 ... ... I'm using this function to group records by ZIP and calculate the median of DATA: aggregate(d$DATA, list(Zip = d$ZIP), FUN=median, na.rm=T) but what I really want to do is to calculate several statistics (median,

I used both BMDP and SAS in my earlier years, side by side. At that time the BMDP statistical methods were much more mature and comprehensive: we treated them as the standard when the two packages disagreed. (It was a BMDP manual that clearly explained to me what the hypothesis of "Yate's weighted mean test" is, something SAS decided to call "type III" and eternally

Dear R-users, I would like to write Greek letters followed by subscripts in a graph (on the X-axis and in a legend). I would appreciate any help. thank you, delphine courvoisier ************************************ Delphine Courvoisier Clinical Epidemiology Division University of Geneva Hospital +4122 37 29029

Alternate title: How can I persuade my students that R is for them? Alternate title: Can R replace SAS, SPSS or Stata for clinicians? I am teaching introductory statistics to twelve physicians and two veterinarians who have enrolled in a Mentored Clinical Research Training Program. My course is the first in a sequence of three. We (the instructors of this sequence) chose to teach R rather than

Dear R-Users, A message to continue the discussions we had in March and June. I have read the documents written since then (http://www.r-project.org/doc/R-FDA.pdf ; http://user2007.org/program/presentations/harrell.pdf ; http://user2007.org/program/presentations/rossini.pdf ; http://user2007.org/program/presentations/soukup.pdf) which are very interesting and useful. I work in a CRO and we

Alistair-- I wrote functions to calculate Clinical Significance in Splus for the following article: McGlinchey, J. B., Atkins, D. C., & Jacobson, N. S. (2002). Clinical significance methods: Which one to use and how useful are they? Behavior Therapy, 33, 529-550. I will send the functions to you back-channel. cheers, Dave -- Dave Atkins, PhD Assistant Professor in Clinical Psychology

Dear guRus, I would like to loop over a medium amount of Sweave code, including both R and LaTeX chunks. Is there any way to do so? As an illustration, can I create a .tex file like this using a loop within a .Rnw file, where the "1,2,3" comes from some iteration variable in R? ################################################ \documentclass{article} \usepackage{Sweave} \begin{document}