Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [conway-maxwell-poisson-distribution]

The Conway-Maxwell-Poisson distribution is a discrete distribution with support over the natural numbers. It has two parameters and can be either over- or underdispersed. It is a member of the exponential family, has the Poisson and geometric distribution as special cases and the Bernoulli distribution as a limiting case.

More information and links to literature can be found at the Wikipedia page.

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Is there a common underdispersed discrete distribution with unbounded support for general mean and variance?

I have a mean $\mu$ and a variance $\sigma^2$ with underdispersion, i.e., $\sigma^2<\mu$. Is there a standard discrete distribution with these moments and unbounded-on-the-right support, i.e., support on $\{0, 1, \dots\}$? Bonus points if it is…
Stephan Kolassa
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Conway-Maxwell-Poisson (CMP) - Coefficient interpretation (Log/IRR)

I'm using the Conway-Maxwell-Poisson (CMP) distribution to model the amount of nouns in a clause (data is under-dispersed). I've run the model using glmmTMB (family= "compois") but I'm having problems interpreting the coefficients. I understand they…
Leandra
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R2 for mixed-effects Conway-Maxwell Poisson using package glmmTMB

After running a mixed-effects Conway-Maxwell Poisson model using glmmTMB, I've printed the results using sjPlot's tab_model() but I don't know what R2 calculation is being used. Is it Nakagawa's R2 since it is a mixed-effects model? Also, I've come…
Leandra
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Modelling underdispersed poisson distribution for count data

I am currently trying to model the count of agent in a system, in which I systematically varied the available space. I figured that I could use a classical Poisson distribution. However, the model is not fitting nicely and there is some trend in it…
Locoric Polska
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Checking Conway-Maxwell-Poisson model adequacy

I am trying to troubleshoot model adequacy problems for underdispersed count data (number of correct responses in a simple task; dispersion ratio is 0.3) that I modeled with Conway-Maxwell-Poisson. The residuals of my model look normally…
gj.
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