I want to fit a function to time series. If I had: x <- 1:4 y <- 1:4
lm(y~x) This would fit a simple line to the four points. But if it is represented as a time series x <- 1:4 t <- ts(x) lm(????) So I have a time series in the object t. How do I write a formula for lm? What do I put in the formula for x and y when I only have t (the time series). Kevin ---- stephen sefick <[EMAIL PROTECTED]> wrote: > what do you want to do? > > On Fri, Sep 5, 2008 at 3:22 PM, <[EMAIL PROTECTED]> wrote: > > I am sorry but I looked at ?lm and could not see any guidance on writting a > > formula. If I have two arrays or a data set then I know how to do that (y ~ > > x) but for a time series I am not sure how to write y or x. > > > > Thank you. > > > > Kevin > > > > ---- Gabor Grothendieck <[EMAIL PROTECTED]> wrote: > >> The Time Series section in ?lm should be self explanatory. If you are > >> using > >> diff's and lag's then look at the dyn package. > >> > >> On Fri, Sep 5, 2008 at 12:25 PM, <[EMAIL PROTECTED]> wrote: > >> > I did a ?lm and it said basically to be careful when using lm and a time > >> > series. But my question is probably more to do with my inexperience that > >> > anything. If I have a time series object 'ti' how do I write the > >> > formula? The response is the value at any particular time and the time > >> > is basically the index of the time series. But I don't know how to put > >> > that into a formula. > >> > > >> > Thank you. > >> > > >> > Kevin > > > > ______________________________________________ > > 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. > > > > > > -- > Stephen Sefick > Research Scientist > Southeastern Natural Sciences Academy > > Let's not spend our time and resources thinking about things that are > so little or so large that all they really do for us is puff us up and > make us feel like gods. We are mammals, and have not exhausted the > annoying little problems of being mammals. > > -K. Mullis ______________________________________________ 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.
