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Dear people, I'm trying to do some analysis of a data using the models by Royle & Donazio in their fantastic book, particular the following function: http://www.mbr-pwrc.usgs.gov/pubanalysis/roylebook/panel4pt1.fn that applied to my data and in the console is as follows: > `desman.y` <- structure(c(3L,4L,3L,2L,1L), .Names = c("1", "2", "3",

Dear all, this is my first time, and just begin to use R. But I've a question about optimization using optimx library. It could sound stupid by I'm a bit affraid with the problem, because anything I try, anything Error. The procedure was: optimx(par="10,71,1",fn=(Prey*Provisioning)/Risk, control=list("maximize)) well the problem lies in the initial value parameters, again

Hi to all the people, I'm working with abundance data of some species, but containing too zero values, and the factors are the ones typical in a BACI experiment (Before-and-After-Control-Impact). Thus, these are two fixed factors. As the data does not holds the normality and homogeneity of variances assumptions of clasiccal ANOVA, I'm trying to fit a zero-altered model using the MCMC glmm

Hi all (again), many thanks for the answer to the optimization problem. All is fine now. The problem now is with kernel estimators in sm. package. I do all the work and the graphics good, but I need the density function data for each point, and I don't know how to get it. The only thing I get is the table at the end of the following sequence: >

Hi to all the people again, I was writting a simply function in R, and wish to collect the results in a excel file. The work goes as follows, Ciervos<-function(K1, K0, A, R,M,Pi,Hembras) {B<-(K1-K0)/A T1<-(R*Pi*Hembras-M*Pi+B)/(Pi-M*Pi+R*Pi*Hembras) P1<-Pi-B R1<-P1*Hembras*R M1<-P1*M T2<-(R1-M1+B)/(P1-M1+R1) P2<-P1-B R2<-P2*Hembras*R M2<-P2*M

Hi to all the people (again), I'm doing some simulations with the memisc package of an own function, but I've the problem that I didn't know how to read the result of such simulations. My function is: > Torre<-function(a1,N1,a2,N2) + {Etorre<-(a1*N1)/(1+a1*N1) + Efuera<-(a2*N2)/(1+a2*N2) + if(Etorre>Efuera)Subir=TRUE + if (Etorre<Efuera)Subir=FALSE +

Dear members of R forum, I'm trying to perform a simply dynamic programming model in R, following the reccomendations of Soetart & Herman (A practical guide to ecological modeling). However, I've obtained a number of problems, that I'm unable to solve (even thoughI've tried during at least 2 hours). Can anyone help me? Many thanks > ccrit <- 0 > cmax <- 5 >

Hi to all the people, I'm having a trouble when trying to plot a quadratic function. I have the code: regression<-nls(Survival~beta1+beta2*PI+beta3*PI^2, data=cubs, start=list(beta1 = 1, beta2 = 1, beta3 = 1)) plot(Survival~PI,data=cubs, ylab="Survival", xlab="PI") lines(cubs$PI, fitted(regression)) but the plotted line is not the quadratic one, rather it appears a

Hi to all of you, I'm fitting an full factorial probit model from an experiment, and I've the independent variables as factors. The model is as follows: fit16<-glm(Sube ~ as.factor(CE)*as.factor(CEBO)*as.factor(Luz), family=binomial(link="probit"), data=experimento) but, when I took a look to the results I've obtained the following: glm(formula = Sube ~ CE * CEBO *

Hello to all the people in the forum, I'm trying to perform a Scheirer-Ray-Hare test in R, and despite I've found some posts talking about this test, there no one in which I can found how to do so. Can anyone explain me how to do the test? Thanks Pablo -- View this message in context: http://r.789695.n4.nabble.com/Scheirer-Ray-Hare-tp3818476p3818476.html Sent from the R help mailing

Dear r-helpers, I'm experiencing some problems in fitting a maximum likelihood binomial model to some of my data. The error is in optim, which founds: Error in optim(par = c(0.2, 0.5), fn = function (p) : initial value in 'vmmin' is not finite Yes, I know it's a common problem, and I've carefully searched and readed all the posts about the issue, But, I can't find a