Displaying 20 results from an estimated 1000 matches similar to: "Error in ppois function (PR#161)"
2008 Aug 21
1
pnmath compilation failure; dylib issue?
(1) ...need to speed up a monte-carlo sampling...any suggestions about
how I can get R to use all 8 cores of a mac pro would be most useful
and very appreciated...
(2) spent the last few hours trying to get pnmath to compile under os-
x 10.5.4...
using gcc version 4.2.1 (Apple Inc. build 5553) as downloaded from
CRAN, xcode 3.0...
...xcode 3.1 installed over top of above after
2004 Jan 15
1
Exactness of ppois
Hello,
by checking the precision of a convolution algorithm, we found the
following "inexactness":
We work with R Version 1.8.1 (2003-11-21) on Windows systems (NT, 2000,
XP).
Try the code:
## Kolmogorov distance between two methods to
## determine P(Poisson(lambda)<=x)
Kolm.dist <- function(lam, eps){
x <- seq(0,qpois(1-eps, lambda=lam), by=1)
max(abs(ppois(x,
2018 Dec 03
2
Bug report: Function ppois(0:20, lambda=0.9) does not generate a non-decreasing result.
function ppois is a function calculate the CDF of Poisson distribution, it should generate a non-decreasing result, but what I got is:
> any(diff(ppois(0:19,lambda=0.9))<0)
[1] TRUE
Actually,
> ppois(19,lambda=0.9)<ppois(18,lambda=0.9)
[1] TRUE
Which could not be TRUE.
Code is tested in both R 3.5.1 and Microsoft R Open 3.5.1.
_
2018 Dec 04
3
Bug report: Function ppois(0:20, lambda=0.9) does not generate a non-decreasing result.
Le 04/12/2018 ? 11:27, I?aki Ucar a ?crit?:
> On Tue, 4 Dec 2018 at 11:12, <qweytr1 at mail.ustc.edu.cn> wrote:
>> function ppois is a function calculate the CDF of Poisson distribution, it should generate a non-decreasing result, but what I got is:
>>
>>> any(diff(ppois(0:19,lambda=0.9))<0)
>> [1] TRUE
>>
>> Actually,
>>
>>>
1997 Jul 09
1
R-beta: Problem with `rpois'
There is a problem with `rpois'. It does seem to take care about the
order of the arguments. This is an example:
> rpois(n=1,lambda=2)
[1] 3
> rpois(lambda=2,n=1)
[1] 2 0
It obviously uses the first argument as the number of samples to be
drawn, which is wrong.
I used Version 0.49 Beta (April 23, 1997).
Fredrik
1997 Jul 09
1
R-beta: Problem with `rpois'
There is a problem with `rpois'. It does seem to take care about the
order of the arguments. This is an example:
> rpois(n=1,lambda=2)
[1] 3
> rpois(lambda=2,n=1)
[1] 2 0
It obviously uses the first argument as the number of samples to be
drawn, which is wrong.
I used Version 0.49 Beta (April 23, 1997).
Fredrik
2004 Jan 09
4
Poisson distribution help requested
Could somebody help me to understand the syntax of R's ppois function? I'm looking to calculate the cumulative probability density of an observed value (y) given the expected mean (mu) and the level of significance (alpha). I'm coming from using SAS to do this and don't recognize the descriptions of the arguments for ppois. The definitions of lambda and p as stated in the R manuals
2006 Sep 20
2
Poission distribution
The expected number of bladder cancer over next 20 years a tire
industry is 1.8. Poission distribution is assumed to hold and 6
reported deaths are caused by bladder cancer among the employees.
Trying to find how unusual this event is.
> ppois(q=6, lambda=1.8, lower.tail = TRUE, log.p = FALSE)
[1] 0.9974306
not sure if ppois is the right one to use and the parameters...
thx much
2009 Mar 17
3
R does not compile any more on FreeBSD 8.0-CURRENT
On a recent FreeBSD 8.0-CURRENT (i386) building R (any version) breaks
with the following messages:
----------------------------------------------------------------------
[...snip...]
gcc -std=gnu99 -I. -I../../src/include -I../../src/include
-I/usr/local/include -DHAVE_CONFIG_H -g -O2 -c wilcox.c -o wilcox.o
gcc -std=gnu99 -I. -I../../src/include -I../../src/include
-I/usr/local/include
2018 Dec 04
0
Bug report: Function ppois(0:20, lambda=0.9) does not generate a non-decreasing result.
>>>>> Serguei Sokol
>>>>> on Tue, 4 Dec 2018 11:46:32 +0100 writes:
> Le 04/12/2018 ? 11:27, I?aki Ucar a ?crit?:
>> On Tue, 4 Dec 2018 at 11:12, <qweytr1 at mail.ustc.edu.cn> wrote:
>>> function ppois is a function calculate the CDF of Poisson distribution, it should generate a non-decreasing result, but what I got is:
2006 Sep 20
1
ppois
A quick question!
The number of episodes per year of otitis media follows a Possion
distribution with lambda = 1.6 episodes per year. Wouldn't the
probability of getting 3 or more episodes of otitis media in the first
2 years of life be:
> ppois(q=3, lambda=1.6*2, lower.tail = TRUE, log.p = FALSE)
[1] 0.6025197
I am confused with the lambda and 3 or more..
thx much
2006 Jun 30
2
Query : Chi Square goodness of fit test
I want to calculate chi square test of goodness of fit to test,
Sample coming from Poisson distribution.
please copy this script in R & run the script
The R script is as follows
########################## start
#########################################
No_of_Frouds<-
c(4,1,6,9,9,10,2,4,8,2,3,0,1,2,3,1,3,4,5,4,4,4,9,5,4,3,11,8,12,3,10,0,7)
N <- length(No_of_Frouds)
# Estimation of
2001 Feb 07
3
Goodness of fit to Poisson / NegBinomial
All,
I have some data on parasites on apple leaves and want to do a
goodness of fit test to a Poisson distribution. This seems to
do it:
mites <- c(rep(0,70),
rep(1,38),
rep(2,17),
rep(3,10),
rep(4,9),
rep(5,3),
rep(6,2),
rep(7,1))
tab <- table(mites)
NSU <- length(mites)
N <-
2004 Jun 20
3
Greater than 1 or less than 1?
I have problem evaluating the expression h = exp(x)/(exp(exp(x))-1) for
large negative x. This expression is actually the probability
that y = 1 when y is a Poisson random variable truncated at 0, hence
must satisfy 0 <= h <= 1. However, when
x < -18, I may get an h value that is larger than 1 while the true
value should be a quantity that is smaller than but very close to 1.
For
2010 Oct 25
2
Ayuda con una función
Reciban un cordial saludo.
De manera muy comedida les pido ayuda con la función indicada abajo. La usan
en un artículo de inventarios. No veo dónde estoy errado.
Gracias de antemano.
César Escalante C.
> lamb<-50
> L<-1
> h.<-10
> p<-25
> K<-5
> integ<-function(y){integrate(function(x)ppois(x,lamb*L),0,y)$value}
> G<-function(y){(h.+p)*integ(y) +
2009 Apr 13
1
dnbinom with a large size parameter (PR#13650)
Full_Name: Andrey Pavlov
Version: 2.7.1 (2008-06-23)
OS: Windows Vista
Submission from: (NULL) (67.193.233.43)
Dear developers,
I discovered an issue with the dnbinom function while fitting a negative
binomial model to my data. I was using the size and mu parameterization. When
the size gets large enough, the function begins to return 1, while it should
instead return the respective Poisson
1999 Jun 09
4
packages with FORTRAN code
Recent sensible changes to the dynload mechanism have made an old
problem resurface: how should we deal with packages which contain
Fortran code and may need to be linked against additional libraries
such as -lf2c?
The current consensus is that extra Fortran libraries maybe needed are
handled via the make variable FLIBS, and that `-lf2c' or `-lg2c' are
added by default if g77 is used.
1998 Mar 25
1
R-beta: qpois help
version .62:
---------------------------------------------
> ?qpois
The Poisson Distribution
dpois(x, lambda)
ppois(q, lambda)
qpois(p, lambda)
rpois(n, lambda)
Arguments:
x: vector of (positive) quantiles.
p: vector of probabilities.
n: number of random values to return.
lambda: vector of positive means.
2018 Feb 09
1
R Compilation gets stuck on Windows 64
Please note that building R on Windows is documented in "R Installation
and Administration", including links to external software. Particularly
there is a link to texinfo which is part of Rtools. The documentation is
maintained and it is a sufficient source of information for building R
on Windows.
https://cran.r-project.org/doc/manuals/r-release/R-admin.html
2010 Oct 17
2
dpois().......bizarre warning messages
Dear Masters,
I have a question to submit
consider the following script
m<-4.95
obs<-rpois(36,m) # i generate 36 realization from a poisson(m)
hist(obs,freq=F)
curve(dpois(x,m),add=T,col="red") #i wish to overlay on the histogram the
theorical poisson density function
errors are returned saing the x vector doesn't contain integers....
really bizarre i can't give