[R-sig-eco] probability distribution for zero-inflated, right skewed data

[Bob O'Hara]

On 16/06/14 13:57, Johannes Björk wrote:
> Dear all,
>
> Im looking into how to fit a GLM model (Im using rjags) with data that are heavily right skewed. In addition, some variables also zero-inflated. The data are species area distribution measured as "total area (km^2)" which is subsetted into "area in tropical zone" and "area in temperate zone". The last two variables contain zeros.
>
> I have google zero-inflated models... and most that come up is "zero-inflated negative binomial" and zero-inflated negative poisson" for count data. I reckon I cannot use any of these distributions since my variables are not discrete.
>
> Any pointer to which distribution(s) that might fit this kind of data would be much appreciated.
I think a Tweedie distribution is sometimes used, but that always makes 
me think of escaping chickens. Recently this was published, which might 
also be useful: 
<http://onlinelibrary.wiley.com/doi/10.1111/2041-210X.12122/abstract>. 
They used BUGS, so you could ask them if the code is available. Even if 
it isn't, it shouldn't be too difficult to code up.

Bob

-- 

Bob O'Hara

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