[R-sig-eco] Calculating EC50s

[Nicholas Lewin-Koh]

Hi,
Short answer: fit a 4 parameter logistic model using nls in base or use
the
package drm. The parameter names differ, but the third parameter is the
ec50.

Longer Answer: Need more information from you to give you a longer
answer.

Nicholas

PS: I changed the title of this thread. Something informative is much
more
 likely to get you useful answers.

> From: Manjunatha Reddy <ahmreddy at yahoo.com>
> Subject: Re: [R-sig-eco] Ordering of nominal or categorical variables
> 	in	randomForest?
> To: Griffith.Michael at epamail.epa.gov, cottenie at uoguelph.ca
> Cc: r-sig-ecology at r-project.org
> Message-ID: <43749.56741.qm at web31811.mail.mud.yahoo.com>
> Content-Type: text/plain
> 
> Dear R Group
> I would like to know about EC50 and its calculation, kindly help me out
> and if you have any information please pass it on to ahmreddy at
> gmail.com, 
> Thanking you with regards
> 
> Dr. A. H. Manjunatha Reddy
> Lecturer, 
> Department of Biotechnology
> R V College of Engineering
> Mysore Rd
> Bangalore – 560 059
> INDIA
> Ph: +91 98445 73697
> 
> --- On Tue, 8/7/08, Karl Cottenie <cottenie at uoguelph.ca> wrote:
> 
> *******************************************