R help - Feb 2005 - estimate the parameter of exponential distribution, etc.

Given a numeric vector of observations, does R have any generic way to estimate
the parameters of commonly used distributions (exponential, gamma, etc.) without
numerically optimizing the likelihood function?

Thanks,
David
_______________________________________
David R. Bickel  http://davidbickel.com
Research Scientist
Pioneer Hi-Bred International
Bioinformatics & Exploratory Research
7250 NW 62nd Ave., PO Box 552
Johnston, Iowa 50131-0552
515-334-4739 Tel
515-334-6634 Fax
david.bickel at pioneer.com, bickel at prueba.info



This communication is for use by the intended recipient and ...{{dropped}}

Le 22 F?vrier 2005 18:01, Bickel, David a ?crit :
> Given a numeric vector of observations, does R have any generic way to
> estimate the parameters of commonly used distributions (exponential, gamma,
> etc.) without numerically optimizing the likelihood function?
Assuming you want to use maximum likelihood estimation, look into
'fitdistr'
in package MASS.

Hope this helps!

-- 
  Vincent Goulet, Professeur agr?g?
  ?cole d'actuariat
  Universit? Laval, Qu?bec 
  Vincent.Goulet at act.ulaval.ca   http://vgoulet.act.ulaval.ca

Hi David,

You can estimate parameters using fitdistr() in MASS
package. 
I suggest also to read my contribute "Fitting
distributions with R" available on CRAN:
http://cran.r-project.org/doc/contrib/Ricci-distributions-en.pdf
Best regards,
Vito



you wrote:

Given a numeric vector of observations, does R have
any generic way to estimate the parameters of commonly
used distributions (exponential, gamma, etc.) without
numerically optimizing the likelihood function?

Thanks,
David
_______________________________________
David R. Bickel  http://davidbickel.com
Research Scientist
Pioneer Hi-Bred International
Bioinformatics & Exploratory Research
7250 NW 62nd Ave., PO Box 552
Johnston, Iowa 50131-0552
515-334-4739 Tel
515-334-6634 Fax
david.bickel at pioneer.com, bickel at prueba.info

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