Thank you very much Murray! Greatly appreciated. :] Chris
Murray Cooper wrote: > > Chris, > > I haven't seen anyone post a reply yet so thought I'd > throw in my thoughts. I'm no R expert! > > When you talk about an exponential trend line are you > refering to: > > 1) y=ax^b > or > 2) y=ae^(bx) > > If 1) then take base10 logs of y and x and then fit them > with simple linear regression. Then calculate the antilog > of the residulas and plot these as your trendline. > > If 2) then take natural logs of y and x and follow the rest > of the procedure described in 1). > > Hope this helps. > > Murray M Cooper, Ph.D. > Richland Statistics > 9800 N 24th St > Richland, MI, USA 49083 > Mail: richs...@earthlink.net > > ----- Original Message ----- > From: "chrisli1223" <chri...@austwaterenv.com.au> > To: <r-help@r-project.org> > Sent: Thursday, January 07, 2010 10:33 PM > Subject: [R] R exponential regression > > >> >> Hi all, >> >> I have a dataset which consists of 2 columns. I'd like to plot them on a >> x-y >> scatter plot and fit an exponential trendline. I'd like R to determine >> the >> equation for the trendline and display it on the graph. >> >> Since I am new to R (and statistics), any advice on how to achieve this >> will >> be greatly appreciated. >> >> Many thanks, >> Chris >> -- >> View this message in context: >> http://n4.nabble.com/R-exponential-regression-tp1009449p1009449.html >> Sent from the R help mailing list archive at Nabble.com. >> >> ______________________________________________ >> R-help@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. >> > > ______________________________________________ > R-help@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. > > -- View this message in context: http://n4.nabble.com/R-exponential-regression-tp1009449p1010914.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@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.
