Displaying 20 results from an estimated 2000 matches similar to: "Problem with fitdistr function while estimating parameters"
2008 Feb 09
1
Problem with fitdistr function
Hello,
I am using fitdistr function for parameter estimation.
When I use
fd<-fitdistr(V2,"gamma")
I get following error:
Error in optim(x = c(0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, :
initial value in 'vmmin' is not finite
fd<-fitdistr(V2,"weibull")
Error in optim(x = c(0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, :
2008 Feb 10
2
Error in optim while using fitdistr() function
Hello,
I am trying to fit distribution for data consisting of 421 readings.It is
basically no of requests arrived per minute.It contains many 0 entries as no
of requests.When i use
fd<-fitdistr(V2,"gamma")
I get following error:
Error in optim(x = c(0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, :
initial value in 'vmmin' is not finite
What should I do ? I need
2008 Feb 10
1
Error in optim while using fitdistr() function for estimation of parameters
Hello,
I am trying to fit distribution for data consisting of 421 readings.It is
basically no of requests arrived per minute.It contains many 0 entries as no
of requests.When i use
fd<-fitdistr(V2,"gamma")
I get following error:
Error in optim(x = c(0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, :
initial value in 'vmmin' is not finite
What should I do ? I need
2008 Feb 10
1
Error while using fitdistr() function or goodfit() function
Try changing your method to "ML" and try again. I tried the run the
first example from the documentation and it failed with the same error.
Changing the estimation method to ML worked.
@List: Can anyone else verify the error I got? I literally ran the
following two lines interactively from the example for goodfit:
dummy <- rnbinom(200, size = 1.5, prob = 0.8)
gf <- goodfit(dummy,
2010 Jan 03
6
Help with function "fitdistr" in "MASS"
Hi, R users:
I want to fit my data into a normal distribution by using the command
"fitdistr" in "MASS".
I changed my data class from "ts" to "numeric" by
>class(mydata)="numeric"
but after using "fitdistr", I got the result below
>fitdistr(mydata,"normal")
mean sd
NA NA
(NA) (NA)
the help doc of
2008 Sep 19
0
Re lative Novice ? "Can I get some explanation of the docs for fitdistr(MASS)?"
In the docs I see:
Usage
fitdistr(x, densfun, start, ...)
Arguments
x A numeric vector.
densfun Either a character string or a function returning a density
evaluated at its first argument.
Distributions "beta", "cauchy", "chi-squared", "exponential", "f", "gamma",
"geometric", "log-normal", "lognormal",
2004 Feb 17
2
problem with fitdistr ?
Hi,
I'm trying fitdistr but I'm getting some errors
> fitdistr(rnorm(100),"Normal")
Error in fitdistr(rnorm(100), "Normal") : 'start' must be a named list
> fitdistr(rnorm(100),"Normal",start=list(mean=0,sd=1))
Error in fitdistr(rnorm(100), "Normal", start = list(mean = 0, sd = 1))
:
supplying pars for the Normal is not
2008 Sep 22
0
Warnings in fitdistr() from MASS.
For a lark, I experimented a bit with the data from Ted Byers' recent
postings. The result of fitdistr() seemed sensible, but I was bothered
by the warnings about NaNs that arose. Warnings always make me nervous.
Explicitly this is what I did:
TXT <- "0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
2008 Sep 22
0
Re lative novice: Working with fitdistr(MASS): 3 questions
OK, I am now at the point where I can use fitdistr to obtain a fit of one of
the standard distributions to mydata.
It is quite remarkable how different the parameters are for different
samples through from the same system. Clearly the system itself is not
stationary.
Anyway, question 1: I require a visual perspective of the fit I get. I can
use hist.scott to get a hisogram (and just have to
2007 Sep 09
1
fitdistr()
I am trying to fit the chi-squared distribution to a set of data using the fitdistr function found in the MASS4 library, the data set is called ONES3, I have loaded it using the command
ONES3<-read.table("ONES3.pdf",header=TRUE,na="NA")
I print out the dataset ONES3 to the screen to make sure it has loaded
Then I try to fit this data using the command
2003 Jul 04
1
Problem with fitdistr for beta
I have the following problem:
I have a vector x of data (0<x<=1 ) with
a U-shaped histogram and try to fit a beta
distribution using fitdistr. In fact,
hist(rbeta(100,0.1,0.1)) looks a lot like
my data.
The equivalent to
the example in the manual
sometimes work:
> a <- rbeta(100,0.1,0.1)
> fitdistr(x=a, "beta", start=list(shape1=0.1,shape2=0.1))1)
> shape1
2013 Oct 28
0
"Optimization fail" error from fitdistr (Weibull distribution)
Hello everyone,
This is Kangmin.
I am trying to produce shape and scale of my wind data. My data is based on
wind speed frequency with 1km/hr increment. data is described below.
Windspeed (km/h) Frequency
1 351
2 147
3 317
4 378
5 527
6 667
7 865
8 970
9 987
10 907
11 905
12 642
13 1000
14 983
15 847
16 842
17 757
18 698
19 632
20 626
21 599
22 529
23 325
24 391
2003 Jul 28
1
Optimization failed in fitting mixture 3-parameter Weibull distri bution using fitdistr()
Dear All;
I tried to use fitdistr() in the MASS library to fit a mixture
distribution of the 3-parameter Weibull, but the optimization failed.
Looking at the source code, it seems to indicate the error occurs at
if (res$convergence > 0)
stop("optimization failed").
The procedures I tested are as following:
>w3den <- function(x, a,b,c)
2011 May 03
3
fitting distributions using fitdistr (MASS)
Please guide me through to resolve the error message that I get
this is what i have done.
>x1<- rnorm(100,2,1)
>x1fitbeta<-fitdistr(x1,"beta")
Error in fitdistr(x1, "beta") : 'start' must be a named list
Yes, I do understand that sometime for the distribution to converge to the
given set of data, it requires initial parameters of the distribution, to
2003 Nov 27
2
MASS fitdistr()
Dear R experts,
I am trying to use the R MASS library fitdistr() to fit the following
list:
k21stsList<-c(0.76697,0.57642,0.75938,0.82616,0.93706,0.77377,0.58923,0.37157,0.60796,1.00070,0.97529,0.62858,0.63504,0.68697,0.61714,0.75227,1.16390,0.66702,0.83578)
as follows,
library(MASS)
fitdistr(k21stsList, "normal")
But, I get
Error in fitdistr(k21stsList, "normal") :
2008 Feb 09
2
print.fitdistr buglet
Dear developers,
There's a small bug in print.fitdistr that can cause output to be printed
twice, but only if print is called explicitly:
> fit<-fitdistr(rt(1000,3),"t")
There were 11 warnings (use warnings() to see them)
> fit
m s df
-0.02181723 1.00145296 3.13723878
( 0.03865057) ( 0.03999447) ( 0.33298377)
> print(fit)
2008 Oct 30
1
Is possible, on biological grounds, suggest to fitdistr (MASS library) that the estimated parameters must be between two values?
Sorry if it is a silly question, I haven't found documentation on this and I
don't know if it is possible.
library(MASS) ## for fitdistr
library(msm) ## for dtnorm
#prepare truncated normal distribution
dtnorm0 <- function(x, mean, sd , log = FALSE) {
dtnorm(x, mean, sd, 105, 135, log)
}
set.seed(1)
#Generate normal distribution with the TRUE population mean (day 106 of the
2010 Jan 28
4
Problems with fitdistr
Hi,
I want to estimate parameters of weibull distribution. For this, I am using
fitdistr() function in MASS package.But when I give fitdistr(c,"weibull") I
get a Error as follows:-
Error in optim(x = c(4L, 41L, 20L, 6L, 12L, 6L, 7L, 13L, 2L, 8L, 22L,
:
non-finite value supplied by optim
Any help or suggestions are most welcomed
--
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2005 Jul 12
1
three par. fitting with fitdistr
Hello,
I want to fit a tree parameter distribution to given data. I tried it with
sample data using the "fitdistr" function.
Here my workflow that didn't had any result:
I started with the generalized gamma distr, which is:
r*dgamma(x^r,shape,rate)
The R-function is:
ggamma = function (x,r,shape,rate) r*dgamma(x^r,shape,rate=rate)
For the first step I assumed r = 1 and I
2011 Oct 28
1
weibull fitdistr problem: optimization failed
I'm getting errors when running what seems to be a simple Weibull
distribution function:
This works:
x <-
c(23,19,37,38,40,36,172,48,113,90,54,104,90,54,157,51,77,78,144,34,29,45,16,15,37,218,170,44,121)
rate <- c(.01,.02,.04,.05,.1,.2,.3,.4,.5,.8,.9)
year <- c(100,50,25,20,10,5,3.3,2.5,2,1.2,1.1)
library(MASS)
x <- sort(x)
tryCatch(
f<-fitdistr(x, 'weibull'),
error