similar to: Buckley-James censored regression without intercept

OK, I am forwarding this to the r-help. In the original message I simply hit reply and I thought I send to ALL r-help list. (apparent not) also I recieved another piece of mail.....about the RNG in Splus 4.0 or later indicating it was modified and getting worse. I only have Splus 3.4 for HP. So I cannot try it. This makes the idea of using the pre-generated RN on CDROM more appealing.. Mai

Dear R community, I wrote and someone else helped me type a 5-page R-info in Chinese, covering the most basic information on how to get and install and start using R on Wintel PC. This could serve those not fluent in/intimidated by English but want to start using R. (I met a lot of those in China) <http://www.ms.uky.edu/~mai/ZhongWen.htm> also a MSword version of the same (may print

Dear r-help, I ran output <- lm(formu, data=mydata) I want to look at the condition number (to see if the matrix is near singular). How? Also, I use the function stepAIC from MASS to select models, how can I see the condition numbers in each step? While I am at it. I find a minor bug: R 1.7.1 on window XP, when you copy and paste by click one button, then the input stopped, until you

Dear helper, I am using linux (redhat) R 1.5.0, in the batch mode. The device png() do not seem to be available. A look at the help says png() is available if I use --gui option. Is there a way to get around it? (to get png("Rplot.png") in batch mode?) The reason I need batch mode is that I am working to get the Rcgi to run. Thanks, Mai Zhou mai at ms.uky.edu

I have commited fixes for 0.64.1 for (1) From: Mai Zhou <mai@ms.uky.edu> > .Random.seed <- c(1, 1:2) > .Random.seed [1] 1 1 2 > runif(5) Warning: Wrong length .Random.seed; forgot initial RNGkind? set to Wichmann-Hill[1] 0.02253721 0.84832584 ........ Here the length of the seed was being tested before the kind was picked out, so the length of the previous type was used. (2)

Hi, I was thinking to ask the University computing Labs here to install R and I was told they need a statement that the software (R) is Y2K compliant. Which I cannot find in CRAN. (in addition to the licensing info). Is it a big issue to put such a statement in R? or this has legal implications that R do not want as a "free" software? If possible I would like to see the statement on

Hello all. I've been attempting to utilize the "survival" pkg ( http://cran.r-project.org/web/packages/survival/index.html), while reading through this guide (http://www.ms.uky.edu/~mai/Rsurv.pdf). I figured working through the guide would be the best way to go, before attempting my own data. I tried to utilize the Kaplain-Meier estimator as shown in the guide:

Hello, I would like to increase the number of iterations for running a Buckley-James regression model in the rms package, but something is apparently syntactically wrong. The following code initially is exactly as it appears in the help page (which runs successfully), then a "failure to converge" message (resulting from specifying an 'identity' link argument, the error message

Full_Name: Mai Zhou Version: 1.9.1 OS: Win XP Professional Submission from: (NULL) (12.222.227.93) > power.t.test(n=25, delta=0.1, sig.level=1.1, strict=TRUE, type="one.sample") One-sample t test power calculation n = 25 delta = 0.1 sd = 1 sig.level = 1.1 power = 1.088311 alternative = two.sided ### power can never be

rms version 3.3-1 has been installed on CRAN. New features/bug fixes are below. * Added new example for anova.rms for making dot plots of partial R^2 of predictors * Defined logLik.ols (calls logLik.lm) * Fixed and cleaned up logLik.rms, AIC.rms * Fixed residuals.psm to allow other type= values used by residuals.survreg * Fixed Predict and survplot.rms to allow for case

Windows 9*/NT version, on an NT box R 0.63.0 Beta (Nov 13, 1998) > library(survival4) > test <- function(x,d) { survfit(Surv(x,d) ~1) } > test( rexp(50), sample(c(0,1), size=50, replace=T) ) Error: Object "x" not found > Other functions like in the ctest library works out OK, the x and d got passed to the inner function. And here it did not got passed to

R 0.64 on windows NT 4.0 Sometimes I got an error message by doing this > .Random.seed <- c(1, 1:2) > .Random.seed [1] 1 1 2 > runif(5) Warning: Wrong length .Random.seed; forgot initial RNGkind? set to Wichmann-Hill[1] 0.02253721 0.84832584 ........ Sometimes I do not get error message: > .Random.seed <- c(1, 1:2) > .Random.seed [1] 1 1 2 > runif(1) [1] 0.5641106 >

Hi just wondering if there is a package that can get the maximum likelihood or method of moments estimator for distributions with censored data? The distributions I'm interested in are: Exponential, pareto, beta, gamma and lognormal. -- View this message in context: http://www.nabble.com/MLE-for-censored-distributions-in-R-tp15022863p15022863.html Sent from the R help mailing list archive at

Dear R-help, > prop.test(9, 137, p=0.066) > prop.test(9, 137, p=0.05) give two different 95% confidence intervals. I thought the confidence interval calculation should be independent of testing calculations (and thus the null hypothesis)? Splus 2000 has similar problems but give slightly different answer. Using R1.3.0 on windows. Mai Zhou

Can anybody give me a neat example of interval censored data analysis codes in R? Given that suvreg(Surv(c(1,1,NA,3),c(2,NA,2,3),type="interval2")~1) works why does survreg(Surv(data[,1],data[,2],type="interval2")~1) not work where data is : T.1 T.2 Status 1 0.0000000 0.62873036 1 2 0.0000000 2.07039068 1 3 0.0000000

Dear R users, I tried to analysis the hazard function of some data by coxph function in survival package. The type of the data include "left-censored", "right-censored", "both right-censored and left-censored" (btw, does this has a technical term?), and "complete" ones. I noticed that event (one parameter in "Surv()") might be an indicator for the

Hi all! I have two survival data sets looking at similar effects in different settings. One data set is only right censored, but the other is interval censored. In the right censored data set, there is an effect of one factor that causes very different shapes in survival curves (and non-proportional hazards) and I'd really like to say that the same factor has a similar effect in the other

One set of data has censored (less-than detection limits) water chemistry concentrations for 80-100% of all observations. My initial trial-and-error attempts to apply the cenboxplot() method suggests that it has an upper limit to the percentage of censored observations. I do not see this limit in Dennis Helsel's second edition. Has anyone experience plotting censored data and can provide

I need to give a quick description of Tobit Regression (TR), including how it differs from ordinary least squares (OLS). I am an ecologist who knows just enough about remote sensing and statistics to be dangerous in both. Now I have found myself doing a remote sensing project where I have used TR: survreg(Surv()). As far as I can tell, no form of Censored Regression has been used in analyzing

I start by doing a simple gaussian tobit by MLE: x1 <- runif(1000) # E() = 0.5 x2 <- runif(1000)*2 # E() = 1 x3 <- runif(1000)*4 # E() = 2 ystar <- -7 + 4*x1 + 5*x2 + rnorm(1000) # is mean 0 y <- ystar censored <- ystar <= 0 y[censored] <- 0 library(AER) m <- tobit(y ~ x1 + x2, left=0, data=D) summary(m) Which gives: Call: