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VGAM package : Frechet distribution - 2 parameter estimation

5 messages · Katherine Gobin, Michael Dewey, Rolf Turner +1 more

Original
Katherine Gobin
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Dear R forum,

I am trying to execute following code (Page no 259 - VGAM.pdf)

# .........................................................................................................................

library(VGAM)

set.seed(123)
fdata <- data.frame(y1 = rfrechet(nn <- 1000, shape = 2 + exp(1)))
with(fdata, hist(y1))
fit2 <- vglm(y1 ~ 1, frechet, data = fdata, trace = TRUE)

# .........................................................................................................................


However, I receive following error 

Error in vglm(y1 ~ 1, frechet, data = fdata, trace = TRUE) : 
  object 'frechet' not found


Earlier there used to be a function called "frechet3" which I guess has been withdrawn by VGAM. 

Kindly guide 

Katherine
Michael Dewey
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On 06/11/2014 06:04, Katherine Gobin wrote:
Is it not called frechet2?

  
    

      
      
    

  


  


      

    

    

      
      

        


  

        

      Katherine Gobin
    

    

      
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Dear Mr Michael,

Thanks a lot for your guidance. The pdf file describing VGAM package has mentioned 'frechet' in the example, so I got the error.

Regards
Katherine

        
On Thursday, 6 November 2014 2:54 PM, Michael Dewey <info at aghmed.fsnet.co.uk> wrote:

        

        
On 06/11/2014 06:04, Katherine Gobin wrote:

            

      
      
      
    

        
Is it not called frechet2?

            

      
      
      
    

        

      
      
    

        

  
    

      
      
    

  


  


      

    

    

      
      

        


  

        

      Rolf Turner
    

    

      
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Dear Ms. Gobin,

There would appear to be a typo in the package manual that appears on 
CRAN.  Doing ?Frechet (it would be nice to have this aliased also to 
"frechet") points you immediately to frechet.  With "frechet2" 
substituted for "frechet" your code, everything works.

cheers,

Rolf Turner

        
On 06/11/14 22:34, Katherine Gobin wrote:

            

      
      
      
    

        

  
    

      
      
    

  


  


      

    

    

      
      

        


  

        

      Thomas Yee
    

    

      
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Hello,

a day or two ago I submitted VGAM 0.9-5 to CRAN, which has
myriads of changes to family functions---their names, their
arguments, and their order thereof. Especially regarding
family functions for discrete and continuous distributions.

In a nutshell, I found lots of inconsistencies while writing
my book, and it was deemed necessary to standardize things.
I just had to bite the bullet, so to speak. I have tried
to summarize all changes in the NEWS file, however, a few
might have gone undocumented. Users of previous versions
of VGAM are cautioned to check their code. My apologies
for this inconvenience.

I have always tried to make it plain that while the
version number was less than 1.0-0, everything was subject
to change. But the book "Vector Generalized Linear and
Additive Models", for Springer, should appear next year,
it is synchronized with version 1.0-0, so that should end
most of these disruptive changes :) Or at least, curtail them
(hopefully).

cheers

Thomas

ps. for this particular problem, only frechet() remains.

        
On 06/11/14 23:12, Rolf Turner wrote: