search for: grofit

Hello, I'm trying to understand grofit's estimation of models, and fairly new to growth models generally. The data used by grofit consists of the vector of "experiments", that is the growth values for a vector of individuals measured at different times. Can I understand correctly that the program estimates parameters for t...

Hello, I would like to ask about the statistic used for initial values for models built with grofit. Is the mean (of the experiments or cases) at t1 used? Also at the other time points? regards, Russell [[alternative HTML version deleted]]

Dear All, I want to use grofit package for biological growth curves. My dataset only includes "age" variable and "size" variable. I want to use logistic, gompertz and richards growth curves to predict age from size. How can I implement this data set to the function in grofit package? Best regards, Deniz...

Hi Is it possible to use grofit to get the AIC of several (e.g. two) growth models and compare both these and model parameters? All I can get it to do so far is return parameters for a single model. Cheers Roland [[alternative HTML version deleted]]

Does anyone know if it is possible to get the length of the log phase (the main growth phase) from a grofit logistic model? I can get the lag phase length, maximum growth and max rate of growth, but I also want to know the length of the log phase (ie, for how long do the bacteria grow exponentially?) Thank you for any help in advance [[alternative HTML version deleted]]

Hello, I'm hoping someone may know the most likely R package for a multivariate population model for comparing groups? That is, I'd like to estimate a (stochastic) model for one batch of experiments against a different batch growing under different conditions. I'm a bit familiar with grofit, but also reading about dse and dlm. Following Bolker's Ch. 11 it seems there are many paths open, and I add that with my data, collection of 5 time points(needed for grofit) is a gargantuan task. I'd be grateful for any advice- regards, shfets

...ression model >model: data ~ logistic(time, A, mu, lambda, addpar) >data: parent.frame() > A mu lambda >0.53243 0.03741 6.94296 ### but I know the formula used is # y~'A'/(1+exp((4*'mu'/'A')*('lambda'-'time'))+2)) # from the grofit ( package I am using to fit the model) documentation. I have attempted to use the R function 'deriv' to get the first derivative from which I can then reuse the deriv function to get the second derivative.... unfortunately this does not seem to work ### >express<-expression(y~'A...

Hi all, How can I overcome the error "object of type 'closure' not subsettable" I ran the following script seq <- paste(seq(1914, 1916, by=1), "*.y", sep=".") # make sequence c <- 3 # total number of files d2 <- file # creates dummy file # Input sequence in loop for (i in 1:3){ list <- list.files("~/ukcp09/txt/x.djf", seq[[i]]) file

...e, how can I deal with > RFE+SVM wrong message? > ? ? ? (bbslover) > ???8. information module Wilks' lambda > criterion (Catherine ENG) > ???9. Transform data set (Thomas Jensen) > ? 10. R-installation regarding. (fredrick devadoss) > ? 11. Re: estimation of parameters with grofit > (alexander russell) > ? 12. Re: Embed R code in C++ (mans) > ? 13. Re: Calling R functions into C# or C++ > (ManInMoon) > ? 14. Re: help with survival package (Shankavaram, Uma > (NIH/NCI) [E]) > ? 15. Re: Transform data set (stephen sefick) > ? 16. Re: Transform data set...