Displaying 20 results from an estimated 600 matches similar to: "CDF of a gamma distribution"
2007 Aug 14
1
Can I calculcate the percentage of a gamma function area below a cutoff value?
Hi there,
I have some bird flight height data that follows a gamma distribution. The
data (x) goes from 0 to 700 meters (n=1055). The calculated parameters
calculated from the fitdistr(x) are (shape = 5.1379, rate = 0.017541), and
therefore the scale (1/rate) = 57.00929. I would like to calculate the
percentage of the function area that occurs below 50 meters (0-50m).
Is that
2007 Oct 07
1
a function to compute the cumulative distribution function (cdf) of the gamma
Un texte encapsul? et encod? dans un jeu de caract?res inconnu a ?t? nettoy?...
Nom : non disponible
Url : https://stat.ethz.ch/pipermail/r-help/attachments/20071006/065906cc/attachment.pl
2008 Nov 24
1
repeated measures regression and power analysis?
Hi there,
I am attempting to assess whether there is a trend in a
observations of a population that was observed on 7 consecutive days in July
for 6 years (2000, 2001, 2002, 2004, 2006, 2008). I have count data of
the number of observations per day for each of the seven days for each of the 6
years (total of 42 days of count data). Is there a package in R
that can accomplish this? I have
2009 May 07
1
data transformation using gamma
Hi R-users,
I have this code to uniformise the data using gamma:
> length(dp1)
[1] 696
> dim(dp1)
[1] 58 12
> dim(ahall)
[1] 1 12
> dim(bhall)
[1] 1 12
> trans_dt <- function(dt,a,b)
+ { n1 <- ncol(dt)
+ n2 <- length(dt)
+ trans <- vector(mode='numeric', length=n2)
+ dim(trans) <- dim(dt)
+ for (i in 1:n1)
+ { dt[,i] <- as.vector(dt[,i])
2006 Aug 07
1
mathematica -> r (gamma function + integration)
Dear R-list,
I try to transform a mathematica script to R.
#######relevant part of the Mathematica script
(* p_sv *)
dd = NN (DsD - DD^2);
lownum = NN (L-DD)^2;
upnum = NN (H-DD)^2;
low = lownum/(2s^2);
up = upnum/(2s^2);
psv = NIntegrate[1/(s^NN) Exp[-dd/(2s^2)]
(Gamma[1/2,0,up] + Gamma[1/2,0,low]),{s,sL,sH},
MinRecursion->3];
PSV = psv/Sqrt[2NN];
Print["------------- Results
2013 Jul 12
2
How to determine the pdf of a gamma distribution using the estimated parameters?
Hello everyone,
With th bar histogram (number of occurrences) hist<-c(24,7,4,1,2,1,1) of seven equally spaces classes ]1-4], ]5-8], ]9-12], ]13-16], ]17-20], ]21-24], ]25-28], I obtained shape=0.8276 and rate=0.1448.
I would like to know how to build the continuous pdf of a this gamma distribution knowing these two estimated parameters such that I will be able to predict the pdf of any
2004 Mar 19
3
Incomplete Gamma Functions and GammaDistribution Doc errata.
Hello all,
In the course of trying to implement the CDF of an
InverseGammaDistribution, I have run across the need for an igamma()
function. Several others have needed this function but the answers I
have found so far are not totally clear to me. I'm writing for three
reasons:
1) to present a small error in the docs
2) to clarify the approach we are expected to take
3) to request,for the
2011 Sep 19
2
Poisson-Gamma computation (parameters and likelihood)
Good afternoon/morning readers. This is the first time I am trying to run
some Bayesian computation in R, and am experiencing a few problems.
I am working on a Poisson model for cancer rates which has a conjugate Gamma
prior.
1) The first question is precisely how I work out the parameters.
#Suppose I assign values to theta with *seq()*
*theta<-seq(0,1,len=500)*
#Then I try out the
2006 Sep 01
1
integration problem with gamma function
Dear R-list members,
I have a problem with translating a mathematica script into R. The whole
script is at the end of the email (with initial values for easy
reproduction) and can be pasted directly into R. The problematic part
(which is included below of course) is
<--- Original Mathematica --->
(* p_svbar *)
UiA = Ni (Dsi - 2Di A + A^2)/2;
UiiA = Nii (Dsii - 2Dii A + A^2)/2;
psvbar =
2007 Feb 27
1
fitting the gamma cumulative distribution function
Hi.
I have a vector of quantiles and a vector of probabilites that, when
plotted, look very like the gamma cumulative distribution function. I
can guess some shape and scale parameters that give a similar result,
but I'd rather let the parameters be estimated. Is there a direct way
to do this in R?
Thanks,
Tim.
week <- c(0,5,6,7,9,11,14,19,39)
fraction <-
2006 Nov 28
3
ML fit of gamma distribution to grouped data
Hello,
we have a set of biological cell-size data, which are only available as
frequencies of discrete size classes, because of the high effort of
manual microscopic measurements.
The lengths are approximately gamma distributed, however the shape of
the distribution is relatively variable between different samples (maybe
it's a mixture in reality).
Is there any ML fitting (or
2008 Jun 11
2
MLE Estimation of Gamma Distribution Parameters for data with 'zeros'
Greetings, all
I am having difficulty getting the fitdistr() function to return without
an error on my data. Specifically, what I'm trying to do is get a
parameter estimation for fracture intensity data in a well / borehole.
Lower bound is 0 (no fractures in the selected data interval), and upper
bound is ~ 10 - 50, depending on what scale you are conducting the
analysis on.
I read in the
2010 Dec 17
3
box-and-whisker plots based on summary not data
Hi,
Is it possible to produce box-and-whisker plots given that I have the
median, interquartile and 5/95th centile values, but not the data from
which they come? It seems that it ought to be possible to coerce bxp
to do what I want, but I can't quite see how.
Thanks,
Matthew
--
Matthew Vernon, Research Fellow
Ecology and Epidemiology Group,
University of Warwick
2009 Nov 09
3
How to transform the Matrix into the way I want it ???
Hi, R users,
I'm trying to transform a matrix A into B (see below). Anyone knows how to
do it in R? Thanks.
Matrix A (zone to zone travel time)
zone z1 z2 z3 z1 0 2.9 4.3 z2 2.9 0 2.5 z3 4.3 2.5 0
B:
from to time z1 z1 0 z1 z2 2.9 z1 z3 4.3 z2 z1 2.9 z2 z2 0 z2 z3 2.5 z3 z1
4.3 z3 z2 2.5 z3 z3 0
The real matrix I have is much larger, with more than 2000 zones. But I
think it should
2007 Nov 28
0
question on cdf compare in R
Dear list,
I was attracted to a comment that the cdf.compare in S+ is not available in R.
I wonder if anyone have more information on this. Thank you.
Ilham
2013 Aug 26
0
Bivariate skew normal cdf; very slow
Dear all,
I am calculating the bivariate skew normal cdf in "sn" package using "pmsn" function.
Although it is quite convenient ( thanks to prof. Azzalini) but it seems to be slow.
For example, it takes about 1 minute in calculation of 100k of such cdf values.
I am thinking to write a c++ code for this although not very familiar with it.
Any other idea?
Thanks in advance,
2009 Sep 06
1
using histogram to find cdf
Dear all,
How can I use the histogram density estimate (hist) to find the value of the cdf at a certain point?
Thanks
Maram
[[alternative HTML version deleted]]
2008 Dec 16
1
How to make a smooth ( linear ) CDF plot?
This question might seem silly, because I felt that it MUST be in the
mailing list archives or help files somewhere, but I simply couldn't find
it.
I want to make some simple CDF (cumulative distribution function) plots
to check whether distributions are Gaussian / normal. But in order to check
how "normal" the distribution is, I really need the y-axis to be Gaussian as
well
2009 Mar 13
0
Fitting GUMBEL Distribution - CDF function ISSUE
Dear R helpers
I am trying to fit the Gumbel distribution to a data. I am using lmom package. I am getting problem in Cumulative Distribution Function of Gumbel distribution as I am getting it as a series of 0's and 1's thereby affecting the P P Plot. My R code is as follows.
library(quantreg)
library(RODBC)
library(MASS)
library(actuar)
library(lmom)
x <-
2006 Apr 26
1
cdf of weibull distribution
Hi,
I have a data set which is assumed to follow weibull distr'. How can I find of cdf for this data. For example, for normal data I used (package - lmomco)
>cdfnor(15,parnor(lmom.ub(c(df$V1))))
Also, lmomco package does not have functions for finding cdf for some of the distributions like lognormal. Is there any other package, which can handle these distributions?