On Wed, 2005-10-12 at 12:01 -0700, t c wrote: > I have a dataset with three variables: date, var1, var2
> How can I calculate the correlation, by date, between var1 and var2? > > e.g. > > > date var1 var2 > 1/1/2001 5 4 > 1/1/2001 8 5 > 1/1/2001 9 7 > > > > 2/1/2001 7 2 > 2/1/2001 2 1 > 2/1/2001 4 6 > > > > 3/1/2001 3 5 > 3/1/2001 4 3 > 3/1/2001 6 9 > 3/1/2001 7 -1 > > > > the results I want: > 1/1/2001 0.891042111 > 2/1/2001 0.075093926 > 3/1/2001 -0.263117406 t c, Given your series of posts here, I would highly recommend that before you consider spending money on a tutor or other similar resource, you take the time to read the freely available documentation that both R Core and useRs have kindly provided to the Community. The R Core manuals are all available with your downloaded installation of R and/or from the main R web site under Documentation as are the Contributed documents. You will find that your time will be well invested in that effort. If you read the Posting Guide for the e-mail lists, a link to which is provided at the bottom of every e-mail that comes through, you will find an excellent guide to the resources that are available to assist you in using R. Trying to learn R (as with any technical endeavor) without reading at least a basic set of the growing list of documents, books and publications on R is going to be problematic. A hint for you here: See ?by, ?tapply, ?split and ?lapply for guidance on how to generate summary statistics on subsets of data. HTH, Marc Schwartz ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html