[ADMB Users] Relationship between NB in ADMB and NB in R

[Ben Bolker]

On 12-02-11 06:07 PM, Mark Maunder wrote:
> Size=(mean^2)/(mean*tau-mean)
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> Because
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> Var=mean*tau
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> And
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> Var=mean+(mean^2)/size
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  Yes.  You can simplify it a bit further:

  size = mu/(tau-1)

or

  tau = (1+mu/size)


>  
> 
> *From:*users-bounces at admb-project.org
> [mailto:users-bounces at admb-project.org] *On Behalf Of *Mark Maunder
> *Sent:* Saturday, February 11, 2012 12:19 PM
> *To:* users at admb-project.org
> *Subject:* [ADMB Users] Relationship between NB in ADMB and NB in R
> 
>  
> 
> How does the tau parameter in the ADMB negative binomial relate to the
> size parameter in R’s dnbinom(x, size, prob, mu, log = FALSE) function?
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>  
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> Mark Maunder          
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>  
> 
> IATTC fall workshop: Using Oceanography for Fisheries Stock Assessment
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> 11-14 October 2011, La Jolla, CA
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> http://www.fisheriesstockassessment.com/TikiWiki/tiki-index.php?page=Using+Oceanography+for+Fisheries+Stock+Assessment+and+Management+2011
> <http://www.fisheriesstockassessment.com/TikiWiki/tiki-index.php?page=Using+Oceanography+for+Fisheries+Stock+Assessment+and+Management+2011>
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