R help - Nov 2003 - MASS fitdistr()

Dear R experts,

I am trying to use the R MASS library fitdistr() to fit the following
list:

k21stsList<-c(0.76697,0.57642,0.75938,0.82616,0.93706,0.77377,0.58923,0.37157,0.60796,1.00070,0.97529,0.62858,0.63504,0.68697,0.61714,0.75227,1.16390,0.66702,0.83578)

as follows,

library(MASS)
fitdistr(k21stsList, "normal")

But, I get

Error in fitdistr(k21stsList, "normal") : 'start' must be a
named list

What am I doing wrong (probably alot!)

Thanks,

Oscar

On Thu, 27 Nov 2003, Oscar Linares wrote:
> Dear R experts,
> 
> I am trying to use the R MASS library fitdistr() to fit the following
> list:
Well, that is not a list!
>
k21stsList<-c(0.76697,0.57642,0.75938,0.82616,0.93706,0.77377,0.58923,0.37157,0.60796,1.00070,0.97529,0.62858,0.63504,0.68697,0.61714,0.75227,1.16390,0.66702,0.83578)
> 
> as follows,
> 
> library(MASS)
> fitdistr(k21stsList, "normal")
> 
> But, I get
> 
> Error in fitdistr(k21stsList, "normal") : 'start' must be
a named list
You omitted the `start' argument, and "normal" is not in the list 
specified in the Details section.
> What am I doing wrong (probably alot!)
It always helps to read through the whole help page rather than guessing.

Given that the MLEs for a normal are known explicitly, why are you doing 
this?

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595

At 15:49 27-11-2003, you wrote:
>Dear R experts,
>
>I am trying to use the R MASS library fitdistr() to fit the following
>list:
>
>k21stsList<-c(0.76697,0.57642,0.75938,0.82616,0.93706,0.77377,0.58923,0.37157,0.60796,1.00070,0.97529,0.62858,0.63504,0.68697,0.61714,0.75227,1.16390,0.66702,0.83578)
>
>as follows,
>
>library(MASS)
>fitdistr(k21stsList, "normal")
>
>But, I get
>
>Error in fitdistr(k21stsList, "normal") : 'start' must be
a named list
Hi

You don?t put the start list, something like this

fitdistr(k21stsList, "normal",list(mean = 0.5 sd = 0.1))

      mean          sd    
  0.74584591   0.17908744 
 (0.04108548) (0.02904255)




Bernardo Rangel Tura, MD, MSc
National Institute of Cardiology Laranjeiras
Rio de Janeiro Brazil