Thanks again. I guess I have been fitting in splus gui and in R Commander, not really calling it myself. I was thinking maybe there was a way to define it as a class or something.
I will have to look at segments. Any thoughts if this might be easy to use with years on an axis? From: Peter Ehlers [via R] [mailto:ml-node+3349445-1733968405-216...@n4.nabble.com] Sent: Friday, March 11, 2011 06:38 PM To: Anthony Seeman Subject: Re: Kendall Theil line as fit? On 2011-03-11 14:43, jonbfish wrote: > Thanks for the response, sorry I didn't post it initially. > > kt.mat<- > function(x,y,z){ > for(i in 1:length(x)){for(j in > 1:length(y)){z[i,j]<-(y[j]-y[i])/(x[j]-x[i])}} > return(z)} > > > kt.slope<- > function(x,y,z,s){ > count<-0 > for(i in 1:length(x)){for(j in 1:length(y)){ > if(j>= i+1) { > count<-count+1 > s[count]<-z[i,j]} > }} > print(count) > return(s)} > > #Site23 > > x<- c(1999,2000,2001,2002,2003,2004,2005,2006,2007,2008,2009,2010) > y<- > c(17.942,3.43,14.062,14.814,13.778,13.706,9.748,13.088,12.1309728,9.644646671,9.134,8.84) > > z<-matrix(0:0,length(x),length(y)) > z<-kt.mat(x,y,z) > z > > s<-c(1:(length(x)*(length(x)-1)/2)) > s<-kt.slope(x,y,z,s) > s > slope=median(s) > intercept=median(y)-slope*median(x) > cbind(slope,intercept) > plot(x,y) > > abline(intercept,slope) Okay, you're using abline() for the KT line. But I still don't know what you're after. From your original post: Is there a way to make it appear like a regression fit instead of a line that extends from the edges of the plot? I would like to have the OLS appear as a dotted line and the KT a solid line but as it is the KT line is longer. So how are plotting your 'regression fit'? abline( lm( y ~ x ) ) would also extend across the plot. I suppose that you could use segments() with the range of x-values. BTW, here's a shorter version of your code: yy <- outer(y, y, "-") xx <- outer(x, x, "-") z <- yy / xx s <- z[lower.tri(z)] slope <- median(s) intercept <- median(y) - slope * median(x) Peter Ehlers > > > -- > View this message in context: > http://r.789695.n4.nabble.com/Kendall-Theil-line-as-fit-tp3344617p3349277.html<http://r.789695.n4.nabble.com/Kendall-Theil-line-as-fit-tp3344617p3349277.html?by-user=t> > Sent from the R help mailing list archive at Nabble.com. ______________________________________________ [hidden email]</user/SendEmail.jtp?type=node&node=3349445&i=0&by-user=t> 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. ________________________________ If you reply to this email, your message will be added to the discussion below: http://r.789695.n4.nabble.com/Kendall-Theil-line-as-fit-tp3344617p3349445.html To unsubscribe from Kendall Theil line as fit?, click here<http://r.789695.n4.nabble.com/template/NamlServlet.jtp?macro=unsubscribe_by_code&node=3344617&code=YXNlZW1hbkBpYXNveWJlYW5zLmNvbXwzMzQ0NjE3fDI0NTMyMDgxOQ==>. -- View this message in context: http://r.789695.n4.nabble.com/Kendall-Theil-line-as-fit-tp3344617p3349497.html Sent from the R help mailing list archive at Nabble.com. [[alternative HTML version deleted]] ______________________________________________ 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.
