similar to: AIC and significance tests

Hi I am struggling to fit a non-linear trend using the likfit function in geoR. Specifically I want a sigmoidal function, something like SSfpl in the nls package to fit the trend. But it seems trend.spatial in geoR only works with lm or glm type models. Any ideas how I can specify the model to calculate the kriging parameters using REML, including the parameters of a sigmoidal trend function

Dear Listers, I got this message when compiling a package: * creating pgirmess-manual.tex ... OK * checking pgirmess-manual.text ... ERROR LaTex errors when creating DVI version. This typically indicates Rd problems. The message is quite explicit but I struggled a lot before understanding that the trouble comes from a single file "selMod.rd" among 44 topics. Even though I have

"Writing R Extensions" says {quotes} If you have a crash which gives a core dump you can use something like gdb /path/to/R/bin/exec/R core.12345 to examine the core dump. If core dumps are disabled... {unquotes} sadly it doesn't go on to say how to enable if core dumps are disabled. I understand that in bash I need to do $ ulimit -c unlimited but this doesn't seem to

I've been developing a package called foobar for a couple of years now. It has evolved through various versions, but has always contained compiled C code. Recently, R CMD check has started generating the following message [START QUOTE] R CMD check foobar_1.7.5.tar.gz * using log directory ?/home/david/foobar/package/foobar.Rcheck? * using R version 2.15.2 (2012-10-26) * using platform:

Greetings, I have recently come into some confusion over weather or not AIC results for comparing among models requires that they be nested. Reading Burnham & Anderson (2002) they are explicit that nested models are not required, but other respected statisticians have suggested that nesting is a pre-requisite for comparison. Could anyone who feels strongly regarding either position

Dear all, Using the quasibinomial and quasipoisson families results in no AIC being calculated. However, a quasi AIC has actually been defined by Lebreton et al (1992). In the (in my opinon, at least) very interesting book by Burnham and Anderson (1998,2002) this QAIC (and also QAICc) is covered. Maybe this is something that could be implemented in R. Take a look at page 23 in this pdf:

Do any R functions incorporate a sample sample size correction (e.g., Burnham and Anderson 1998). Thanks, Hank Stevens Martin Henry H. Stevens, Assistant Professor 338 Pearson Hall Botany Department Miami University Oxford, OH 45056 Office: (513) 529-4206 Lab: (513) 529-4262 FAX: (513) 529-4243 http://www.cas.muohio.edu/botany/bot/henry.html http://www.muohio.edu/ecology

Full_Name: David Pleydell Version: 2.2.1 OS: Debian Etch Submission from: (NULL) (193.55.70.206) There appears to be a conflict between the chol functions from the Matrix and the SparseM packages. chol() can only be applied to a matrix of class dspMatrix if SparseM is not in the path. with gratitude David > library(Matrix) > sm <- as(as(Matrix(diag(5) + 1), "dsyMatrix"),

I have been working on an R package that calls C code using .C(). I recently started including some functions from the GNU Scientific Library in my code. The code runs fine on my machine when not wrapped in the package. But I get the following error from "R CMD check" * checking whether the package can be loaded ... ERROR Loading required package: splancs Loading required package: sp

Hi, I have a trouble trying to use \href in a rd doc. See example below: \references{ \href{http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2702787/}{Vaniscotte A., Pleydell D., Raoul F., Quere J.P., Coeurdassier M., Delattre P., Li T., Qian W., Takahashi K., Weidmann J.C., Qiu J., Giraudoux P. 2009 Modelling and spatial discrimination of small mammal assemblages: an example from western

I have a slight conundrum. I'm attempting to write a scrip that will take a number of objects (lm, glm, and lmer) and return AIC scores and weights. I've run into 3 problems, and was wondering if anyone had any pointers. 1) is there any convenient way to extract the name of the objects? Simply, if I have a vector of objects c(my.lm, my.lmer) and I want to get a character

I am experiencing strange results using dmvnorm. I define a scaled distance matrix from the coordinates bellow and then calculate a covariance matrix using a spherical correlation function. Then with certain combinations of range and sill parameters dmvnorm is returning values greater than 1. Surely the results of dmvnorm should be in the interval 0:1 (or do I just nead a holiday?). In addition

Hello, I'd like to say that it's clear when an independent variable can be ruled out generally speaking; on the other hand in R's AIC with bbmle, if one finds a better AIC value for a model without the given independent variable, versus the same model with, can we say that the independent variable is not likely to be significant(in the ordinary sense!)? That is, having made a lot of

Please, forgive my ignorance on statistics, but I have a rather simple question concerning AIC. Small values of AIC mean good fit of the model. How about negative values of AIC? Is a model with AIC=0.5 considered to have better fit than a model with AIC=-500? I couldn't find anything explaining this in the documentation or any elementary statistics textbook that I have at my disposal. Thanks

hello, could somebody refer me to the reason R uses -2*loglik + 2*(#param)+2 to calculate AIC? thank you -- Stoyan Iliev

Hi All, Sorry for this basic question as I am new to this R. I would like to know, is it possible to consider a matrix with some columns having numeric data and some other's with characters (strings) data? How do I get this type of data from a flat file. Thanks very much, mallika ____________________________________________________________________________ Mallika Veeramalai, Ph.D.,

I am trying to do a classic R -d valgrind --vanilla < mypkg-Ex.R as described in http://cs.swan.ac.uk/~csoliver/ok-sat-library/internet_html/doc/doc/R/2.9.1/doc/manual/R-exts.html#Using-valgrind The problem is valgrind crashes imediately. I am using Ubuntu 10.04 LST (actually Biolinux) on a 64bit Dell Precision laptop with 4 core-i5 Intel processors. I have R-2-15-0 installed from source

I have a data file with indicates pretest scores for a linguistics experiment. The data are in long form so for each of 33 subjects there are 400 rows, one for each item on the test, and there is a column called ‘Correct’ that shows ‘C’ for a correct response and ‘E’ for an incorrect response. I am trying to write a formula that will create a vector that indicates the number of correct answers

Hi all, Could anybody please help me understand AIC and BIC and especially why do they make sense? Furthermore, I am trying to devise a new metric related to the model selection in the financial asset management industry. As you know the industry uses Sharpe Ratio as the main performance benchmark, which is the annualized mean of returns divided by the annualized standard deviation of returns.

Dear All, I have a list of models(1000) which have variable scores from 20 different method. I would like to rank models using consensus approach based on high scores from different methods.Is there any function available in R for this purpose? I will appreciate any pointers in this regard. Thank you very much in Advance, Mallika