Re: [R] Fitting data using Generalized Pareto Distribution

2016-11-27 Thread Rui Barradas
Hello, Why quantile(train, 0.9) ? If you use quantile(train) it seems to fit the data much better. You haven't posted a data example so I've made up one. library(eva) # needed for rgpd() library(extRemes) set.seed(1) train <- rgpd(1e3, scale = 0.9, shape = -0.4) thresh90 <- quantile(train)

Re: [R] Fitting data using Generalized Pareto Distribution

2016-11-27 Thread TicoR
Let the train be the data set consisting of numbers that I need to fit. Code is as follows: library(extRemes) thresh90 <- quantile(train, 0.90) model<-fevd(train,threshold =thresh90,type="GP") Model returns the following : Negative Log-Likelihood Value: 317.7561 Estimated parameters: scal

Re: [R] Fitting data using Generalized Pareto Distribution

2016-11-27 Thread Rui Barradas
Hello, Please provide us with a reproducible example. A data exampla would be nice and some working code, the code you are using to fit the data. Rui Barradas Em 27-11-2016 15:04, TicoR escreveu: I am trying to fit some data using Generalized Pareto Distribution in R using extRemes package(h

Re: [R] Fitting data and removing outliers

2012-07-13 Thread David L Carlson
Vogric" , r-help@r-project.org Sent: Friday, July 13, 2012 3:15:25 PM Subject: Re: [R] Fitting data and removing outliers They are due to measurement error, sample of a different population, or ... ? What is the unusual event? Does it explain something important about the system that you

Re: [R] Fitting data and removing outliers

2012-07-13 Thread Stephen Sefick
, July 13, 2012 3:24 PM To: David L Carlson Cc: Lauren Vogric; r-help@r-project.org Subject: Re: [R] Fitting data and removing outliers Do you have a good reason to throw these points out? On Fri, Jul 13, 2012 at 2:17 PM, David L Carlson wrote: I didn't actually see any question in this posting

Re: [R] Fitting data and removing outliers

2012-07-13 Thread stephen sefick
Do you have a good reason to throw these points out? On Fri, Jul 13, 2012 at 2:17 PM, David L Carlson wrote: > I didn't actually see any question in this posting, but instead of removing > the outliers consider using a robust linear model. > > library(MASS) > ?rlm > > The TeachingDemos package h

Re: [R] Fitting data and removing outliers

2012-07-13 Thread David L Carlson
I didn't actually see any question in this posting, but instead of removing the outliers consider using a robust linear model. library(MASS) ?rlm The TeachingDemos package has a data set called outliers to show what can happen when you iteratively remove "outliers" in the way you suggest.

Re: [R] fitting data

2009-01-14 Thread Ben Bolker
Serebrenik, A. tue.nl> writes: > > Dear all, > > I have a set of data which seem to be distributed almost exponentially but > only on [0;1]. I guess that the probability distribution in this case > would look like > > \frac{lambda}{1-e^{-\lambda}) e^{-\lambda x} > > I would like to use fitdis

Re: [R] Fitting data to a sigmoidal curve

2008-11-12 Thread Rubén Roa-Ureta
Greg Snow wrote: Sarah, Doing: RSiteSearch('gompertz', restrict='functions') At the command prompt gives several promising results. Hope this helps, -- Gregory (Greg) L. Snow Ph.D. And you can also do: nobs <- length(data$salam.size.observed) fn<-function(p){ salam.size.mod

Re: [R] Fitting data to a sigmoidal curve

2008-11-12 Thread Greg Snow
Sarah, Doing: > RSiteSearch('gompertz', restrict='functions') At the command prompt gives several promising results. Hope this helps, -- Gregory (Greg) L. Snow Ph.D. Statistical Data Center Intermountain Healthcare [EMAIL PROTECTED] 801.408.8111 > -Original Message- > From: [EMAIL PR

Re: [R] Fitting data to a sigmoidal curve

2008-11-12 Thread Gabor Grothendieck
Try this command from within R: RSiteSearch("gompertz") On Wed, Nov 12, 2008 at 1:50 PM, sarahkm <[EMAIL PROTECTED]> wrote: > > Hi- > I'm a biologist trying to figure out the growth rate of salamanders in > different ponds. I collected individuals from various populations at > different dates, an

Re: [R] Fitting data to a sigmoidal curve

2008-11-12 Thread Rolf Turner
On 13/11/2008, at 7:50 AM, sarahkm wrote: Hi- I'm a biologist trying to figure out the growth rate of salamanders in different ponds. I collected individuals from various populations at different dates, and using the size and date collected, I want to figure out the growth curve of each popu

Re: [R] Fitting Data to a Noncentral Chi-Squared Distribution using MLE

2007-09-11 Thread Charles C. Berry
This is what I might do: > y <- rchisq( 1000, df=10, ncp=2 ) > library( stats4 ) > res <- mle( function(x,z) -sum( dchisq(y, x, z , log=TRUE ) ), start=list( > x=5, z=5 ) ) > coef(res) x z 10.355711 1.586123 > > ## or just to keep clear of boundary constraints: > > res <- mle(