similar to: testing the significance of the variance components using lme

Dear R-users, I want to fit a linear model with Y as response variable and X a categorical variable (with 4 categories), with the aim of comparing the basal category of X (category=1) with category 4. Unfortunately, there is another categorical variable with 2 categories which interact with x and I have to include it, so my model is s "reg3: Y=x*x3". Using fit.contrast to make the

Hello, I've had no luck finding an R package that has the ability to estimate a Tobit model allowing for heteroskedasticity (multiplicative, for example). Am I missing something in survReg? Is there another package that I'm unaware of? Is there an add-on package that will test for heteroskedasticity? Thanks for your help. Cheers, Alan Spearot -- Alan Spearot Department of Economics

Could somebody program this kind of plot type to R, if none exists, based on mds or correlation tables or some more suitable method? What do you think about idea? Does it work? None similar or better exists? http://weightedassociationmap.blogspot.com/ Atte Tenkanen University of Turku, Finland

Hi, i have a vector filled with names: [1] Alvaro Adela ... [25] Beatriz Berta ... ... [100000] ... I would like to drop last character in every name. I use the next program: for (i in 1:100000) { ? ? ? ? ? ? ? ? ? ? ? ? ? largo <- nchar(names[i]-1) ? ? ? ? ? ? ? ? ? ? ? ? ? names[i] <- substring (names[i],1,largo] ? ? ? ? ? ? ? ? ? ? ? ? ?} Is another and faster way of do it? Thanks,

Hi, While I was working, the follwing message flud the screen. Aug 13 23:32:28 www /kernel: Limiting closed port RST response from 213 to 200 packets per second The /var/log/apache_ssl_engine.log started to grow with similar messages: [13/Aug/2004 23:43:49 66440] [error] SSL handshake failed (server www.beco.hu:443, client 217.102.90.240) (OpenSSL library error follows) [13/Aug/2004 23:43:49

Hi R-users, I am using arima to fit a time series. Now I would like to include an intervention component "It (0 before intervention, 1 after)" using different types of impacts, that is, not only trying the simple abrupt permanent impact (yt = w It ) with the xreg option but also trying with a gradual permanent impact (yt= d * yt-1 + w * It ), following the filosophy of Box and Tiao

Hi R-Users, I have plotted a region whose polygon coordinates are given in shp format ED50 UTM (zone=30) ) using "readShapePoly" in library(maptools). Now I need to plot a set of points in that region (my.dataframe, with X and Y geographic coordinates), which have been read using GPS in Longitud-Latitud form (using WGS84 system), so I first need to convert these Longitud-Latitud data

Hi all, I found similar sequences in the /var/auth.log files of freebsd boxes, I supervise.: Aug 13 13:56:08 www sshd[26091]: Illegal user test from 165.21.103.20 Aug 13 13:56:11 www sshd[26093]: Illegal user guest from 165.21.103.20 Aug 13 13:56:15 www sshd[26096]: Illegal user admin from 165.21.103.20 Aug 13 13:56:18 www sshd[26103]: Illegal user admin from 165.21.103.20 Aug 13 13:56:21 www

I am using nonlinear regression to fit a couple of variables to a set of measurements. I would like to do some significance tests for the estimated parameters. I am able to check the confidence intervals using the Jacobian coming out of nonlinear regression. I do see in a paper which shows t-value (it says estimated by White method??), f-value, f-test, and j-test, are these available in matlab,

Hallo! I found a question exactly as mine, but I did not found an answer. Therefore?I post this again - hopefully there will be an answer! Thanks in advance! karl From: Berta <ibanez> Date: Tue, 27 Feb 2007 18:58:48 +0100 Hi R-users, I want to calculate the sample size needed to carry out a 2-sample proprotion test. I have the hypotesized treatment probability of success (0.80), the

I tried your code, but it's giving the following error.. Error in match.fun(FUN) : argument "FUN" is missing, with no default

Full_Name: Peter Solymos Version: 2.8.1 OS: Windows Submission from: (NULL) (129.128.141.92) The help page of the Box.test function (stats) states that the Ljung-Box test was published in: Ljung, G. M. and Box, G. E. P. (1978), On a measure of lack of fit in time series models. Biometrika 65, 553--564. The page numbers are incorrect. The correct citation should be as follows: Ljung, G. M.

http://biomet.oxfordjournals.org/cgi/reprint/86/3/677 biometrika1999 http://biomet.oxfordjournals.org/cgi/reprint/94/4/1006 biometrika2000 Hi All: I just want to try some luck. I am currenly working on my project,one part of my project is to reanalysis the kenward cattle data by using the method in Mohsen's paper,but I found I really can get the same or close output as he did,so,any

Hallo everyone, excuse me if this is not a genuine R question but I do not know where to ask else. Referring to e.g. https://stat.ethz.ch/pipermail/r-help/2004-December/062114.html I wonder if these measurements of 3000 criminals (raw data) are available anywhere. At least I didn't find them in the R datasets package or by means of Google. What I did find was a table of frequencies of

I think you've badly misinterpreted the purpose of the R listserv with this request: https://www.stat.math.ethz.ch/mailman/listinfo/r-help says "The `main' R mailing list, for announcements about the development of R and the availability of new code, questions and answers about problems and solutions using R, enhancements and patches to the source code and documentation of R,

To enhance my understanding, and that of my students, I have a question about cox.zph in the survival package. If I have correctly gleaned the high-level point from the 1994 Biometrika paper of Grambsch and Therneau, it looks to me like cox.zph provides a mechanism to test for a simple trend in plots of a function of time, g(t) versus the scaled schoenfeld residuals and it also provides some

Hello, can anybody here explain what a Jonckheere-Terpstra test is and whether it is implemented in R? I just know it's a non-parametric test, otherwise I've no clue about it ;-( . Are there alternatives to this test? thanks for help, Arne

Hello All, Specifying 'type = "response"' when using predict() on a model fit using glm(...,family="binomial") returns fitted probabilities. Is it possible to get the same from a model object fit using glmmPQL() ? Thanks in advance, Rob _____________________________________________________ Rob Keefe Lab: (208) 885-5165 M.S. student

Hi, I am currently trying to do a GLMM on a dataset with percent cover of seagrass (dep. var) and a suite of explanatory variables including algal (AC) and epiphyte cover (EC), rainfall, temperature and sunshine hours. M2=glmer(SG~AC+EC+TP+SS+RF+(1|Location/fSi/fTr), family=binomial,data=data,nAGQ=1) As the dependent variable is percent cover, I used a binomial error structure. I also have a

Dear R experts, I was wondering if there are any R functions that give the tail area of a sum of chisquare distributions of the type: a_1 X_1 + a_2 X_2 where a_1 and a_2 are constants and X_1 and X_2 are independent chi-square variables with different degrees of freedom. Thanks, Klaus -- "Feel free" - 5 GB Mailbox, 50 FreeSMS/Monat ...