similar to: help with multiple comparisons

Dear R community I sent a message out a while ago asking for help with multiple comparison tests for ANOVA's, but haven't had any response yet. I'm sending a final desperate plea. If I can't get this done in R I'm going to have to redo a whole lot of stuff in a commercial package, which I'm REALLY not keen to do! My problem is how to implement these tests in R. Below

Hi again Sorry, in looking again at sammon and isoMDS I see that they seem to do exactly what I want, except that they are non-metric, which means, as I understand it, that they relate the rank orders of the variables rather than the actual distances. Could I use these non-metric MDS packages even if my distances are metric? Thanks Karen -- Karen Kotschy Centre for Water in the Environment

Hi everyone I'm trying to generate a vector of the form a <- c(1,2,3,4,1,2,3,1,2,1) where n = 5 in a general way, where n can be any positive integer. I've run out of ideas. Does anyone have any suggestions? Thanks Karen Karen Kotschy Centre for Water in the Environment University of the Witwatersrand Johannesburg Tel: 011 716-2218

Hi everyone I'm trying to generate a vector of the form a <- c(1,2,3,4,1,2,3,1,2,1) where n = 5 in a general way, where n can be any positive integer. I've run out of ideas. Does anyone have any suggestions? Thanks Karen Karen Kotschy Centre for Water in the Environment University of the Witwatersrand Johannesburg Tel: 011 716-2218

Dear helpRs Does anyone have an elegant way of doing the following: For a given numeric vector, e.g. vec <- c(3,2,6,4,7) Create a series of vectors where all but 1 of the values are replaced by 0's, e.g. vec.a <- c(3,0,0,0,0) vec.b <- c(0,2,0,0,0) vec.c <- c(0,0,6,0,0) vec.d <- c(0,0,0,4,0) vec.e <- c(0,0,0,0,7) I have looked at `replace', but can't think of a

Hi I asked a while ago about multiple comparison tests for use with multi--way ANOVAs. Thanks to all those who replied and gave me some ideas and functions. What I ended up doing was writing my own function for Tukey's HSD test (ref: Zar's Biostatistics pg 186-190), as this was the procedure I could best understand. I've included my function here for those who may be interested.

Another question: Is it possible to move R objects from one directory to another without copying the whole .RData and .Rhistory files? (I'm running under Linux) Thanks Karen Kotschy Centre for Water in the Environment University of the Witwatersrand Johannesburg Tel: 011 716-2218 -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read

Hi Could somebody please explain the following to me: If x is a 10x10 matrix, typing x[3] prints all 10 values of column 3, although the length of the vector =1. Why? x[,3] and x[[3]] both give all 10 values of column 3, length=10. What is the difference between these two, actually? Thanks Karen Kotschy Centre for Water in the Environment Department of Botany University of the Witwatersrand

Dear R list Would anyone be able to tell me whether it is possible to do "enhanced multidimensional scaling" (enhanced MDS) in R? In other words, something that goes beyond "cmdscale" by iteratively improving the fit between observed dissimilarities and inter-object distances, using the KYST algorithm (Kruskal, 1964). I have found several implementations of non-metric MDS

Does anyone know if an R plug-in exists for the GIS package ArcView running under Windows98 or NT? I know such a plug-in is available for S-PLUS. Thanks Karen Kotschy Centre for Water in the Environment Department of Botany University of the Witwatersrand Johannesburg South Africa Tel : +2911 716-2218 Postal address: P/Bag 3 P.O Wits 2050 South Africa

Hi R users Does anyone out there have a better/quicker way of adding a factor column to a data frame based on levels of another factor? I have a (large) data frame consisting of records for individual plants, each represented by a unique ID number. The species of each plant is indicated in the column "species", which is a factor column with many different levels (species). There are

Dear R community Have just recently got back into R after a long break and have been amazed at how much it has grown, and how active the list is! Thank you so much to all those who contribute to this amazing project. My question: I am trying to calculate Mahalanobis distances for a matrix called "fgmatrix" >dim(fgmatrix) [1] 76 15 >fg.cov <- cov.wt(fgmatrix)

Hello again I'm trying to put error bars onto a barplot. I've tried something that Bill Simpson suggested a while ago, ie: x<-c(1,2,3,4,5) y<-c(1.1, 2.3, 3.0, 3.9, 5.1) ucl<-c(1.3, 2.4, 3.5, 4.1, 5.3) lcl<-c(.9, 1.8, 2.7, 3.8, 5.0) plot(x,y, ylim=range(c(lcl,ucl))) arrows(x,ucl,x,lcl,length=.05,angle=90,code=3) #or segments(x,ucl,x,lcl) but I can't get it to work on a

The Partek package (www.partek.com) allows only two selections for Multiple Test Correction: Bonferroni and Dunn-Sidak. Can anyone suggest why Partek implemented Dunn-Sidak and not the other methods that R has? Is there any particular advantage to the Dunn-Sidak method? R knows about these methods (in R 2.1.1): > p.adjust.methods [1] "holm" "hochberg" "hommel"

Dear R-group, Could somebody recommend a package that can deal with a multinomial response variable (choice of breeding tactic in mice, which has four unordered levels), multiply-imputed data (generated using the Amelia package) and two non-nested random effects: individual identity (133 individuals made up to four choices each) and year (for which there are six levels and sample size varies

Hi, I have two questions want to ask. 1. If I have a matrix like this, and I want to figure out the rows whose value in the 3rd column are less than 0.05. How can I do it with R. hsa-let-7a--MBTD1 0.528239197 2.41E-05 hsa-let-7a--APOBEC1 0.507869409 5.51E-05 hsa-let-7a--PAPOLA 0.470451884 0.000221774 hsa-let-7a--NF2 0.469280186 0.000231065 hsa-let-7a--SLC17A5

I append below a suggested update for p.adjust(). 1. A new method "yh" for control of FDR is included which is valid for any dependency structure. Reference is Benjamini, Y., and Yekutieli, D. (2001). The control of the false discovery rate in multiple testing under dependency. Annals of Statistics 29, 1165-1188. 2. I've re-named the "fdr" method to "bh" but

Also Consider Bonferroni Hochberg Holm type procedures or . Dunn OJ. Multiple contrasts using rank sum tests. Technometrics 1964;6:241#/52. [[alternative HTML version deleted]]

Dear help list Does anybody know if it is possible to somehow tell R to let LaTeX handle the fonts for postscript plots produced by R? It is for a thesis and I have MANY figures. These are created by R scripts dynamically as the document is compiled, using the Make system. I see that I can `manually' specify the font family each time I call the postscript device, but I am looking for a

Dear R-Gurus I am a PhD student from South Africa working on chimpanzee behaviour. I am looking at patterns of shade utilization and am using generalized linear mixed models to examine the effects of various factors on whether chimpanzees choose to spend time in the sun or shade. I realise that the lme4 package and the outputs of the lmer functions have been discussed ad nauseum but I have been