Re: [R] force glm estimates to be nonnegative

From: Samu Mäntyniemi <samu.mantyniemi_at_helsinki.fi>
Date: Fri, 25 Apr 2008 11:03:57 +0300

You could use the BRugs package and formulate your prior knowledge about   slopes in terms of a probability distribution.

Michele Christina Itten kirjoitti:
> Is there a way to force certain formula parameters to be nonnegative?
>
> What I want to do is to estimate student capacity over time, namely by
>

>>  capacity ~ Student + Student:Day

>
> I add this formula to a glm call and obtain negative learning slope estimates (Student:Day) in some cases.
> However, I don't want to allow for that. In such a case, glm should solve
>
>> capacity ~ Student

>
> and I will set the slope to zero.
>
> Is there an option to constrain a parameter set to nonnegative values?
>
>
>
>
> Many thanks in advance!
>
> Michele Itten,
> BS. Carnegie Mellon
>
> ______________________________________________
> R-help_at_r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
>
-- 
------------------------------------------
Samu Mäntyniemi
Researcher
Fisheries and Environmental Management Group (FEM)
Department of Biological and Environmental Sciences
Biocenter 3, room 4414
Viikinkaari 1
P.O. Box 65
FIN-00014 University of Helsinki

Phone: +358 9 191 58710
Fax: +358 9 191 58257

email: samu.mantyniemi_at_helsinki.fi
personal webpage: http://www.helsinki.fi/people/samu.mantyniemi/
FEM webpage: http://www.helsinki.fi/science/fem/

______________________________________________
R-help_at_r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Received on Fri 25 Apr 2008 - 08:06:03 GMT

Archive maintained by Robert King, hosted by the discipline of statistics at the University of Newcastle, Australia.
Archive generated by hypermail 2.2.0, at Fri 25 Apr 2008 - 08:30:33 GMT.

Mailing list information is available at https://stat.ethz.ch/mailman/listinfo/r-help. Please read the posting guide before posting to the list.

list of date sections of archive