Displaying 20 results from an estimated 1100 matches similar to: "ppois"
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,
>>
>>>
1999 Apr 09
7
Error in ppois function (PR#161)
Full_Name: Murray H Smith
Version: 0.63.3
OS: Windows NT
Submission from: (NULL) (130.216.5.57)
The ppois function is displaced by -0.5.
Try:
> ppois(-0.5,1)
[1] 0.3678794
> ppois(-0.51,1)
[1] 0
> ppois(0,1)
[1] 0.3678794
and
> par(mfrow=c(2,1))
> x<-seq(-1,5,0.01)
> plot(x,ppois(x,1),type="s",ylab="F(x)",main="Poisson CDF?")
>
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,
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
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:
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
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)$value}
> G<-function(y){(h.+p)*integ(y) +
2007 May 31
1
Problems when linking to R shared library
Folks,
I'm fairly sure that I'm doing something stupid, but I'm getting a few
really strange results from *some* of the distributions, but by no means
all,
when I link directly to the R shared library.
I've tried this on both Windows with the precompiled Mingw binary of R-2.5.0
(compiling my code with MinGW-3.4.2), and by building R-2.5.0 on Mandriva
Linux with gcc-3.4.4 and
2017 Aug 04
2
Latin hypercube sampling from a non-uniform distribution
Hello,
I am performing a sensitivity analysis using a Latin Hypercube sampling. However, I have difficulty to draw a Hypercube sample for one variable. I?ve generated this variable from a Poisson distribution as follows:
set.seed(5)
mortality_probability <- round(ppois(seq(0, 7, by = 1), lambda = 0.9), 2)
barplot(mortality_probability, names.arg = seq(0, 7, by = 1), xlab = "Age
2008 Jul 30
2
Bizarre - R crashes on merge
Hi all,
I have a large data.frame, 1530 observation with 6 columns. I want to
merge a 7th column, a transformation of the response variable (hospital
admissions), namely
trans<-sqrt(copd$admissions+0.25)
trans<-data.frame(trans)
And now when I do
copd2<-merge(copd,trans)
(copd being my original data.frame), R either crashes or is taking an
extremely long time to do the computation. I
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
2012 Aug 28
1
Bionomial and possion
Make a plot in R where you compare the probability distributions for the
Binomial distributions with N=1000 trials and succes probability 0.005 and
the Possion Distribution with rate lambda=5.
My answer is
b<-binom(x, 1000, 0.005, log = FALSE)
plot(b)
p<-dpois(x, lambda, log = FALSE)
plot(p)
*Is this the right way to solve the problem?*
--
View this message in context:
2003 Mar 29
1
Goodness of fit tests
I have a dataset which I want to model using a Poisson distribution, with a given parameter. I would like to know what is the proper way to do a ''goodness of fit'' test using R.
I know the steps I''d take if I were to do it ''manually'': grouping the numbers into classes, calculating the expected frequencies using ''ppois'', then
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
2008 Jul 21
1
Subsetting data by date
Hi all,
Firstly I appologise if this question has been answered previously,
however searching of the archives and the internet generally has not
yielded any results.
I am looking in to the effects of summer weather conditions
(temperature, humidity etc), on the incidences of a breathing disorder
brought on through smoking (COPD). I am fairly new to R and completely
new to the idea of
2008 Jul 22
4
Opening files from R terminal - appologies
Dear all,
I appologise for cluttering up the list with such a basic question,
however I have been unable to find the answer I want (possibly through
my poor usage of the R help system).
As I am visually impaired and using assistive technology, I think I
would prefer to use R from the terminal mode, i.e. by running rterm.exe
found in the bin directory.
I have managed to set my working
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
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
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