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...or 2 minor 4.0 year 2006 month 10 day 03 svn rev 39566 language R version.string R version 2.4.0 (2006-10-03) Any help is appreciated. Unfortunately the RSiteSearch is not working now, so the question may not be well researched. Thanks Ritwik Sinha Graduate Student Epidemiology and Biostatistics Case Western Reserve University ritwik.sinha at gmail.com | +12163682366 | http://darwin.cwru.edu/~rsinha

Dear all, I tried to use "step" function to do model selection, but I got an error massage. What I don't understand is that data as data.frame worked well for my other programs, how come I cannot make it run this time. Could you please tell me how I can fix it? ***************************************************************************************************

...mething obvious here. How do I get the Kaplan-Meier estimate function that is created by survfit and plotted by the code. fit <- survfit(Surv(time, status) , data=aml) plot(fit) That is, I need a function that will give me the survival estimate at a given time: \hat{S}(t). Thanks in advance. Ritwik Sinha ritwik.sinha at gmail.com | +12033042111 | http://ritwik.sinha.googlepages.com/

Hello, I was wondering if I can plot two curves I get from "density(data)" into one plot. I want to compare both. With the following commad, I just get one curve plotted: plot( density(mydata) ) Sorry for this stupid question but I could not find a solution until now... Antje

...- rpart(Surv(stop, event) ~ rx + size + number, bladder1) print(fit) summary(fit) plot(fit, uniform=T, branch=.4, compress=T) text(fit, use.n=T) Here is an excerpt from summary(fit): Node number 56: 8 observations events=0, estimated rate=0.1858292 , mean deviance=0.2035427 Thanks in advance, Ritwik > R.Version() $platform [1] "i386-pc-mingw32" $arch [1] "i386" $os [1] "mingw32" $system [1] "i386, mingw32" $status [1] "" $major [1] "2" $minor [1] "10.0" $year [1] "2009" $month [1] "10" $day [...

Hello, I am interested in plotting my regression analysis results(regression coefficients and standard errors obtained through OLS and Tobit models) in the form of graphs.What is the best way to accomplish this? Thanks. Murali Kuchibhotla [[alternative HTML version deleted]]

I''m looking for a R function which can maximise this logliklihood function, under the constraits a>0 e b>0 f<-function(param){ a<-param[1] b <-param[2] log(prod)-(a*s2)-(b*s)-n*log(1-((0.5*b/sqrt(a))*(exp((b^2)/(4*a)))*((sqrt(pi ))*(1-pnorm(-b/(2*sqrt(a)), mean=0, sd=1)))))} I''ve tried maxlik constrOptim e donlp2 but without success. Thanks so

Dear all, I want to design a histogram and I need to have the frequency at certain points. For example I have the following 2 columns: *X Y* 0.1 25 0.4 22 0.45 11 0.55 21 I want the chart to have 4 columns. First column is from 0.0-0.1 (on X) and frequency is 25. Next colum is wider and form 0.1-0.4 with 22 frequency. Next column is narrow with 11 frequency and the last column is

I was reading about the project drawer feature in Textmate, which is Mac only. Is there a similar feature in a Windows based text editor that works with R. This feature sounds really useful. Thanks, Graham [[alternative HTML version deleted]]

Hi All, I have a data output as below.I want to display them in an interactive html report using shiny but the data table is not rendering properly and instead giving NA values. max_usage_hours_per_region<-setNames(aggregate(df3_machine_region$sum_as_hours~df3_machine_region$Region,df3_machine_region,max),c("Region","Sum_as_Hours")) Region Sum_as_Hours 1 Africa 1156.0833

Hi All, I have a data output as below.I want to display them in an interactive html report using shiny but the data table is not rendering properly and instead giving NA values. max_usage_hours_per_region<-setNames(aggregate(df3_machine_region$sum_as_hours~df3_machine_region$Region,df3_machine_region,max),c("Region","Sum_as_Hours")) Region Sum_as_Hours 1 Africa 1156.0833

Hi, Suppose I have a multivariate response Y (n x k) obtained at a set of predictors X (n x p). I would like to perform a linear regression taking into consideration the covariance structure of Y within each unit - this would be represented by a specified matrix V (k x k), assumed to be the same across units. How do I use "lm" to do this? One approach that I was thinking of

...#......................................................................................... for(i in 1:choose(n-1,m-1)){ R=B[i,] } *************************************************************************** Can you please help me how to get rid of these errors. Thanking you in advance. Regards Ritwik Bhattacharya Senior Research Fellow SQC & OR UNIT, KOLKATA INDIAN STATISTICAL INSTITUTE Voice : +91 9051253944 This mail is scanned by Ironport

Hi ! I am trying to get at the covariance of the predictions of a linear model. Suppose the we have: > x<-runif(1000) > y<-2 + 25x*x +rnorm(1000) > lm1 <-lm(y~x, data = data.frame(y = y, x=x)) > x.pred <-runif(10) > y.hat <- predict(lm1, newdata = data.frame(x=x.pred)) I was wondering how to get an estimate of the covariance of y.hat which would be a 10 x 10

...ncol=m, byrow=TRUE )) } ########################################################### when I put m=1 error shows : Error in vector("list", gamma(n + 1)) : vector size specified is too large . But it works fine with other values of m (< n). Any suggestion will be highly accepted. Ritwik Bhattacharya SRF, Indian Statistical Institute Kolkata This mail is scanned by Ironport

hie when i use plot.survfit to plot more than one graph why I only see the last graph how do i see the other graphs.for example n=20 n1=n/2 n2=n/4 a11=4;a12=4 ;a21=4 ;a22=4 t1<-array(1,c(n1)) t2<-array(2,c(n1)) treatgrp=matrix(c(t1,t2))

Hi R users I have a dataset which represents points that are market by patients as the source of pain. Basically the patients indicates by a cross on a chest pictures where he/she thinks is the source of pain. The data was then digitalized by divinding the chest into small squares and each square was give value 1 if it was the center 2 if it was touched by the markings and 3 if it was not

Hi, Sorry for the question, I know it should be basic knowledge but I'm struggling for two hours now. How do I select only the first entry of each list member and ignore the rest? So for > $"121_at" > -113691170 > $"1255_g_at" > 42231151 > $"1316_at" > 35472685 35472588 > $"1320_at" > -88003869

I would like to buy a basic statistics book (experimental design, sampling, ANOVA, regression, etc.) with examples in R. Or download it in PDF or html format. I went to the CRAN contributed documentation, but there were only R textbooks, that is, textbooks where R is the focus, not the statistics. And I would like to find the opposite. Other text I am trying to find is multivariate data

...gt; That said, it is very difficult to separate out R questions when mixed into shiny code, so you would help yourself and this list to work on minimal reproducible examples that focus on the R syntax if possible for posts here. Read the Posting Guide. > > On November 7, 2020 2:42:58 AM PST, Ritwik Mohapatra <ritm84 at gmail.com> wrote: >> Hi All, >> >> I have a data output as below.I want to display them in an interactive >> html >> report using shiny but the data table is not rendering properly and >> instead >> giving NA values. >> >...