search for: muhlberg

...d model w/ optim? I can't seem to find anything like a Wald test whose documentation says it applies to optim output. Also, thanks again to everyone who gave me feedback on the robustness of ML estimation in R! Peter ******************************** ******************************** Peter Muhlberger Visiting Professor of Political Science Institute for the Study of Information Technology and Society (InSITeS) Carnegie Mellon University

I'm trying to use the source command to run commands from a file. For instance: source("do.R"), where do.R is a file in the same directory in which I am running R. The contents of do.R are: ls() print("hello") sum(y1) mean(y1) After source("do.R"), all I see is: > source("do.R") [1] "hello" I'm using the X11 version of R for

A newbie question: I'm trying to decide whether to run a maximum likelihood estimation in R or Stata and am wondering if the R mle routine is reasonably robust. I'm fairly certain that, with this data, in Stata I would get a lot of complaints about non-concave functions and unproductive steps attempted, but would eventually have a successful ML estimate. I believe that, with the

Hi, does anyone out there have a recommendation for multilevel / random effects and longitudinal analysis? My dream book would be something that's both accessible to a non-statistician but rigorous (because I seem to be slowly turning into a statistician) and ideally would use R. Peter

I'm used to statistical languages, such as Stata, in which it's trivial to pass a list of variables to a function & have that function modify those variables in the existing dataset rather than create copies of the variables or having to replace the entire dataset to change a few variables. In R, I suppose I could paste together the right instructions in a function and then execute

Apologies if this has been posted about recently, but I haven't been on this listserve for a while. I ran into a problem trying to compile Hmisc (required package for rms) and have found a solution that I'd like to share. The compile fails with the message: /usr/bin/ld: cannot find -lquadmath libquadmath exists on my Debian Squeeze system (up-to-date, recently installed): ldconfig -p

On Wed, 4 Jan 2006, Peter Muhlberger wrote: One comment in advance: please use a more meaningful subject. I would have missed this mail if a colleague hadn't pointed me to it. > I'm someone who from time to time comes to R to do applied stats for social > science research. [snip] > I would also prefer not to have...

I'd like to be able to test linear hypotheses after setting up and running a model using optim or perhaps nlm. One hypothesis I need to test are that the average of several coefficients is less than zero, so I don't believe I can use the likelihood ratio test. I can't seem to find a provision anywhere for testing linear combinations of coefficients after max. likelihood. Cheers

Dear R-packages list members, Last month, Peter Muhlberger posted a message to the r-help list that suggested, among other things, a desire for a more convenient method of performing Wald tests for statistical models fit in R. Thanks largely to Achim Zeleis's help, the linear.hypothesis function in the car package has been reworked so that (1) it i...

I'm contemplating doing Bayesian estimation in R but am wondering how Bayesian estimation on R stacks up against BUGS. Is R reasonably complete, more difficult to use,...? Anyone care to share their experience? Also, am I right to conclude that covariance structure analysis & confirmatory factor analysis are not available in R? (I can't find them with help) Peter

I must have messed up my R environment, but don't know how or how to undo it. The problem is this: I paste the following into R: test<-function() { print("hello") } And I see this: > test<-function() + { + .print("hello") + } > test() Error in test() : couldn't find function ".print" > When I do the same in a fresh environment, I see

Dear R-packages list members, Last month, Peter Muhlberger posted a message to the r-help list that suggested, among other things, a desire for a more convenient method of performing Wald tests for statistical models fit in R. Thanks largely to Achim Zeleis's help, the linear.hypothesis function in the car package has been reworked so that (1) it i...

Does anyone know how -log(x) can equal 743 but -log(x+0)=Inf? That's what the following stream of calculations suggest: Browse[2]> -log ( 1e-323+yMat2 - yMat1 * logitShape(matrix(parsList$Xs, nrow = numXs, ncol=numOfCurves), matrix(means, nrow = numXs, ncol=numOfCurves, byrow=TRUE), matrix(sigmas, nrow = numXs, ncol=numOfCurves, byrow=TRUE)) )[5,9] [1] Inf Yet: Browse[2]>

Full_Name: peter muhlberger Version: 2.7.1 OS: Ubuntu x86_64 dual core Submission from: (NULL) (70.238.206.13) I've spent half a day generating .dta files using write.dta only to have them crash my copy of Stata. I eventually discovered that removing a string variable with a maximum observed length of 280 characters...

...d most > difficult. Then send that to this list. If readers can copy a few > lines of R code from your email into R and try a couple of things in > less than a minute, I think you might get more useful replies quicker. > > Best Wishes, > Spencer Graves > > Peter Muhlberger wrote: > > > Hi Spencer: Thanks for your interest! Also, the posting > guide was helpful. > > > > I think my problem might be solved if I could find a way to > terminate nlm or > > optim runs from within the user-given minimization function > they call....

Hi, I'm new to R. I was wondering if anyone has an OS X native installation (not Carbon) of R on a G3 Macintosh that is able to run linear regression? I installed Jan de Leeuw's R binary for OS 10.2 Jaguar on my laptop, which is still a G3 model. When I try to run a simple regression, using lm, I get an "Illegal Instruction" message and R quits. Jan thinks it may be the case

Hi folks: I guess my earlier posting was too involved, so let me try to get to the essence of my problem. I recently tried to compile JGR, rJava, etc. into my updated R. First, I ran: R CMD javareconf. The output from that tells me that "JAVA_HOME is not a valid path, ignoring" and the cpp flags are set to nothing. The javareconf fills most of the variables with references to

I'm trying to put together an R routine to conduct unidimensional unfolding scaling analysis using maximum likelihood. My problem is that ML optimization will get stuck at latent scale points that are far from optimal. The point optimizes on one of the observed variables but not others and for ML to move away from this 'local optimum', it has to move in a direction in which the

Thanks to everyone who replied to my question! A comment regarding Thomas's point below: Java & other object-oriented languages that are function rather than macro based usually provide methods & other capabilities that allow pass by reference in certain cases and these methods would solve the problem I posed regarding how to change values in an existing data.frame from within a

I've used optim to analyze some data I have with good results, but need to correct the var-cov matrix for possible effects of clustering of observations (respondents) in small groups (non-independence). Is there any function to adjust the matrix? I heard some time ago that the vcovHC function would have a cluster capability added to it, but I don't see that in my fairly recent version.