[R-sig-eco] Help PCNM analysis

2011-10-05 Thread Emma Gothe
Dear list members! I am trying to perform a PCNM analysis with function PCNM() (binary package provided by the provided by project Spatial ecological data analysis with R). I recently ran into a problem. I have a triangular distance matrix based on the shortest distance between my sampling poin

Re: [R-sig-eco] Help PCNM analysis

2011-10-05 Thread Jari Oksanen
On Wed, 2011-10-05 at 10:25 +0200, Emma Gothe wrote: > Dear list members! > > I am trying to perform a PCNM analysis with function PCNM() (binary package > provided by the provided by project Spatial ecological data analysis with R). > I recently ran into a problem. I have a triangular distance

Re: [R-sig-eco] Help PCNM analysis

2011-10-05 Thread Emma Gothe
Thank you Jari for a fast reply! I will try the vegan function asap as it seems to work smoothly. I am still wondering what causes the problem in the PCNM () function though... If anyone else knows, then please let me know. Best Emma -Ursprungligt meddelande- Från: Jari Oksanen [mail

[R-sig-eco] trouble in fitting a distirbution

2011-10-05 Thread matteo dossena
Hi All, I'm trying to fit a theoretical distribution to some data, following the procedure on Bolker's Ecological Models and Data in R, but I'm having some problem... could someone please point me out what I'm doing wrong? here is the code #create a random variable x <- sort(rpareto(100,1,0.

[R-sig-eco] Calculating an AIC for the Fisher's log series.....

2011-10-05 Thread Cory Redman
I am trying to calculate an AIC for my Fisher's log series (fisherfit). In order to do this I need the log likelihood. Does anyone know how to calculate the log likelihood for a specific alpha value. I know that the second derivative of the log-likelihood is used to calculate the standard error

Re: [R-sig-eco] Calculating an AIC for the Fisher's log series.....

2011-10-05 Thread Peter Solymos
Cory, There is a profile method for fisherfit. If that's not enough, you can have a look inside of fisherfit, and you'll see the Dev.logseries internal function and how it is used in nlm to get estimate of alpha. The same function can be used for manual profiling to get likelihood values for a seq

Re: [R-sig-eco] Calculating an AIC for the Fisher's log series.....

2011-10-05 Thread Jari Oksanen
On 5/10/11 20:42 PM, "Cory Redman" wrote: > I am trying to calculate an AIC for my Fisher's log series (fisherfit). In > order to do this I need the log likelihood. Does anyone know how to > calculate the log likelihood for a specific alpha value. I know that the > second derivative of the log

Re: [R-sig-eco] Help PCNM analysis

2011-10-05 Thread François Gillet
Dear Emma, The main difference between PCNM::PCNM and vegan::pcnm functions is that PCNM provides an immediate assessment of the spatial autocorrelation (Moran's I) displayed by the computed eigenfunctions. The problem with your data is that the computation of Moran's I is stopped, probably due to