R help - May 2011 - outout clarification of fitdist {fitdistrplus} output

Hello,

 

I like to fit data against a negative binominal distribution

 

x2<-c(rep(10,14),rep(9,8),rep(8,13),rep(7,11),rep(6,6),rep(5,18),rep(4,7),re
p(3,21),rep(2,33),rep(1,55),rep(0,225))

f2<-fitdist(x2,"nbinom",method="mle")

plot(f2)

summary(f2)

gofstat(f2)

 

I receive the following result:

 

Fitting of the distribution ' nbinom ' by maximum likelihood 

Parameters : 

      estimate Std. Error

size 0.3397148 0.03775577

mu   1.7787630 0.16429774

Loglikelihood:  -701.0615   AIC:  1406.123   BIC:  1414.16 

------

I am wondering how to translate the size and the mu parameter into the usual
number of successes (n) and the contiuous probability (p) . To me it is not
clear what these mu and size parameter declares. 

 

Help is appreciated

 

Best 

Alex

 

 


	[[alternative HTML version deleted]]

Alexander Kapeller <mail <at> alexander-kapeller.de> writes:
> 
> Hello,
> 
> I like to fit data against a negative binominal distribution
> 
 [snip]
> I am wondering how to translate the size and the mu parameter into the
usual
> number of successes (n) and the contiuous probability (p) . To me it is not
> clear what these mu and size parameter declares. 
> 
  See the help page for ?dnbinom, which gives the details of the
different parameterizations ...

   Ben Bolker