[R] locfit smoothing question (package maintainer not reachable)

Suresh Krishna madzientist at gmail.com
Tue Mar 3 21:26:48 CET 2009


David Winsemis wrote:

> I think you should read (or re-read)  the locfit help page and *also*  
> the links from that page to the help pages for locfit.raw and rv. I  
> would have thought that since family= is not an argument to locfit per  
> se, but rather is documented in locfit.raw that you have yet done so,  
> but perhaps not?

I did read the help pages for locfit.raw, and found:

"Local likelihood family; "gaussian"; "binomial"; "poisson"; "gamma" and  
"geom". Density and rate estimation families are "dens", "rate" and  
"hazard" (hazard rate). If the family is preceded by a 'q' (for example,  
family="qbinomial"), quasi-likelihood variance estimates are used.  
Otherwise, the residual variance (rv) is fixed at 1. The default family is  
"qgauss" if a response y is provided; "density" if no response is  
provided. "

However, since the fake data were generated from a known gaussian  
distribution, I did not imagine that using family=gaussian would lead to  
such wildly different results. This is what I was hoping to understand,  
without having to struggle with Catherine's Loader book in order to  
understand the above paragraph deeply enough that this behavior makes  
sense.

Thanks again, Suresh




More information about the R-help mailing list