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Hello, I've been fitting a random effects model using nlme to some data, but I am discovering that the variation in my random effect is very small. As a result, I would like to replace it as a fixed...

Hello, I am wondering if it is possible to run separate lines of code within switch() as one can do in most languages. For example, I'd like to have switch execute a few lines of code based on the...

Hello, I am currently using R to run an external program and then read the results the external program sends to the stdout which are tsv data. When R reads the results in it converts it to to a list...

Hi Kingsford, That's exactly what I was looking for! Thanks. Mike On Thu, 22 Oct 2009, Kingsford Jones wrote: > help(gnls, pack=nlme) > > > hth, > Kingsford Jones > > On Thu, Oct 22, 2009 at 4:36 PM, Michael A. Gilchrist <mikeg...

Hello, I'm trying to do some non-linear regression with 2 cell types and 4 tissue type treatments using selfStart models Following Ritz and Streibig (2009), I wrote the following routines: ##Selfstart expDecayAndConstantInflowModel <- function(Tb0, time, aL, aN, T0...

Hi Dieter, Thanks for the reply. I had played with the initial conditions, but apparently not enough. I finally found some that avoided the singularity issue. Many thanks. More generally, I went over the documentation yet again in P&B...

Hi Dan, No, I hadn't thought of that and it WORKS! I was hoping there'd be such a simple solution. I have new respect for the power of {} w/in R. Many thanks! Mike ----------------------------------------------------- Department of Ecology & Evolutionary...

Sorry, I misunderstood what I was doing and misspoke. I don't think there's a bug. I had called COMMAND w/in read.delim. Thanks for all of your help and sorry for the misinformation. Sincerely, Mike ----------------------------------------------------- Department of...

Wow, that's elegant and simple. It's also faster than my approach. NB, you don't need to use close(), read.delim() closes the pipe when its done reading. Thank you all for your suggestions, they really helped me...

Hello, Excuse me for posting two questions in one day, but I figured it would be better to ask my questions in separate emails. I will again give the caveat that I'm not a statistician by training, but have...

Hello, I will start out with the caveat that I'm not a statistician by training, but have a fairly decent understanding of probability and likelihood. Nevertheless, I'm trying to fit a nonlinear model to a dataset which has...

On Sat, 17 Oct 2009, Douglas Bates wrote: > On Fri, Oct 16, 2009 at 7:09 PM, Michael A. Gilchrist <mikeg at utk.edu> wrote: >> Hello, >> >> I'm having problems creating and using a selfStart model with nlme. >> ?Briefly, I...

Hello, I'm having problems creating and using a selfStart model with nlme. Briefly, I've defined the model, a selfStart object, and then combined them to make a selfStart.default model. If I apply getInitial to the selfStart model...

Hi, I've been trying to work with the gnls() function in the "nlme" package. My decision to use gnls() was so that I could fit varPower and such to some of the data. However, in working with a small...