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Questions tagged [poisson]

The Poisson distribution is a statistical discrete distribution for describing events occurring at random intervals. It is defined on the non-negative integers that has the property in which the mean is equal to the variance.

The Poisson probability distribution is used to model the probability of a number of events occurring during a specified time interval.

The Poisson distribution is characterized by an expected arrival rate, usually designated by the Greek lower-case letter lambda.

A discrete random variable X has a Poisson distribution indexed by a parameter λ if it has probability mass function as following:

enter image description here

Useful links:

Wikipedia entry for the Poisson distribution.

How do I generate discrete random events with a Poisson distribution?

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pcl:TextureMesh from pcl::PointXYZRGBNormal and pcl::PolygonMesh

I have got a pcl::PolygonMesh as poisson reconstruction from pcl::PointCloud::Ptr. I want to create a TextureMesh from both... but how?
user2011909
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Compare Histogram to Poisson Distribution and Gauss-Curve

I got 100 experimental values: N = np.array([ 6080, 5604, 5972, 5566, 5683, 5619, 5582, 5912, 5614,5837, 5961, 5972, 5807, 5829, 5881, 5757, 5725, 5809, 5626, 5995, 5793, 5608, 5880, 5982, 5748, 6071, 6181, 6034, 6117, 5903, 6190, 5735, 6109, 6126,…
lrsp
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Estimating Posterior in Python?

I'm new to Bayesian stats and I'm trying to estimate the posterior of a poisson (likelihood) and gamma distribution (prior) in Python. The parameter I'm trying to estimate is the lambda variable in the poisson distribution. I think the posterior…
John Alberto
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Understanding Non-homogeneous Poisson Process Matlab code

I have found the following Matlab code to simulate a Non-homogeneous Poisson Process function x = nonhomopp(intens,T) % example of generating a % nonhomogeneousl poisson process on [0,T] with intensity function intens x = 0:.1:T; m = eval([intens…
Sunhwa
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glmmadmb help: multiple errors when running models

I'm trying to run a mixed effects model that includes three fixed effects with interaction and a random intercept and slope. The model I'm trying to specify in glmmadmb is: > fit_zipoiss_ambig<-glmmadmb(AmbigCount~Posn.c*mood.c*Valence.c +…
keelybebbington
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Unpredictable poisson noise

I'm in the process of comparing two sets of values for which I apply poisson noise. Below is my code and the corresponding result: import numpy as np import pylab size = 14000 # 1) Creating first array np.random.seed(1) sample =…
prodev_paris
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glmmadmb error: function maximizer failed (couldn't find STD file)

I am trying to run a glmmadmb model with standardized abundance as the response with a random effect of region plus fixed effects of julian day and elevation with a poisson distribution and zero inflation. My code is as…
Andrew
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Error with custom density function definition for mle2 formula call

I want to define my own density function to be used in the formula call to mle2 from R's bbmle package. The parameters of the model are estimated but I cannot apply functions like residuals or predict on the returned mle2 object. This is an example…
Iliya Markov
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Negative binomial dispersion parameter in Matlab

The matlab function nbinfit returns the values r and p for the negative binomial. Is there an equivalent MLE function in matlab that instead returns the values for mu (mean) and theta (the dispersion parameter) for the "ecological" or "Polya"…
user2855666
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Strange error in GLM

I'm creating multiple poisson regressions, each model with different outcome. On this particularly outcome which is not different from the others (all binary, either 0 or 1) I get this strange error that I've never seen before. mix_1<- glm(count~…
Heala45
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hand-rolled R code for Poisson MLE

I'm attempting to write my own function to understand how the Poisson distribution behaves within a Maximum Likelihood Estimation framework (as it applies to GLM). I'm familiar with R's handy glm function, but wanted to try and hand-roll some code…
Austin
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Poisson Distribution in Java (correctness?)

I have to generate data for a Poisson distribution. My range is n = 1000 up to 100K. Where n is the number of data elements; k varies from 1 to n. It says to use lambda as n/2 I have never taken stats and have no idea how to get the correct curve…
Dixon Steel
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How to obtain new samples from ZIP or ZINB-model for bayesian p-value

Hopefully someone can help me with this one, because I am really stuck and do not find my coding error! I am fitting zero-inflated poisson / negative binomial GLMs (no random effects) in JAGS (with R2Jags) and everything is fine with the parameter…
Woosah
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Poisson Disk distribution on hemisphere

I just implemented Poisson Disk generation in the plane with this simple algorithm: http://people.cs.ubc.ca/~rbridson/docs/bridson-siggraph07-poissondisk.pdf Now I would like to generate a Poisson Disk distribution on the surface of a hemisphere (or…
Mat
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ns3 poisson traffic model

I'm trying to learn ns3, and I'm trying to modify one of the examples by using the onofApplication to generate Vbr instead of Cbr, but the code is not working and I don't know why, can you help me please? #include "ns3/core-module.h" #include…
user1653150
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