[R] How can I extract information from list which class is nls

[Joshua Wiley]

Hi,

One way would be:

summary(nls.object)[["coefficients"]][, "Std. Error"]

If you have a hankering to do it yourself rather than go through the
summary formula, the code here will get you there:
getAnywhere("summary.nls")

If you are going to be doing it a lot, creating a little function might be nice:

se.coef.nls <- function(model) {
  summary(model)[["coeffficients"]][, "Std. Error"]
}

se.coef.nls(yourmodel)

I have been doing something along those lines for a number of models.
Sadly, there is not a consistent name always given to the parameter or
coefficients table, so it will not quite be one size fits all, but
generally using str(), you can figure out what the names of what you
want are so it is not much trouble to get out.

str(summary(yourmodel))

Cheers,

Josh

On Tue, Apr 26, 2011 at 11:21 AM, Schatzi <adele_thompson at cargill.com> wrote:
> How do I extract the standard error of the parameter estimates?
>
> Also, if I would like to add two parameters together (x+y), can I use this
> equation to calculate the new standard error?:
> x = parameter 1
> y = parameter 2
> xSE = SE parameter 1
> ySE = SE parameter 2
>
> NewSE=(x+y)*sqrt((xSE/x)^2+(ySE/y)^2)
>
>
>
> --
> View this message in context: http://r.789695.n4.nabble.com/How-can-I-extract-information-from-list-which-class-is-nls-tp804151p3476154.html
> Sent from the R help mailing list archive at Nabble.com.
>
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-- 
Joshua Wiley
Ph.D. Student, Health Psychology
University of California, Los Angeles
http://www.joshuawiley.com/