thanks, it works! well, now it shows 1s instead of 0s and 2s instead of 1s, which fine with me...but could you explain me what this function actually does?
Gabor Grothendieck wrote: > > Iff dd is your data frame then: > > dd$prev <- ave(dd$of, dd$Id, FUN = function(x) c(NA, head(x, -1))) > > > On Wed, Oct 21, 2009 at 2:55 AM, clion <birt...@hotmail.com> wrote: >> >> Dear Rlers, >> in the following dataset I would like to insert a new column that refers >> to >> the data of the previous row. >> My question is whether the probability of a female (Id) changes if she >> had >> given birth to a pup in the previous year. So my dataframe consists of >> the >> column Id, year (2003-2007 for each Id) and offspring (=of; 1-0): >> Id year of >> 1 2003 1 >> 1 2004 0 >> 1 2005 1 >> 1 2006 1 >> 1 2007 0 with 1= female (Id) gave birth to offspring (same year) >> 2 2003 0 and 0 = female didn't pup >> 2 2004 1 >> 2 2005 1 >> 2 2006 0 >> 2 2007 1 >> 3 2003 1 >> 3 2004 1 >> 3 2005 1 >> 3 2006 0 >> 3 2007 0 >> Now I want to add the column "offspring in the previous year - >> yes/no(1-0)" >> the output now should look like this: >> >> Id year of of_inPreviousYear >> 1 2003 1 NA >> 1 2004 0 1 >> 1 2005 1 0 >> 1 2006 1 1 >> 1 2007 0 1 >> 2 2003 0 NA >> 2 2004 1 0 >> 2 2005 1 1 >> 2 2006 0 1 >> 2 2007 1 0 >> 3 2003 1 NA >> 3 2004 1 1 >> 3 2005 1 1 >> 3 2006 0 1 >> 3 2007 0 0 >> >> any idea how I could program that? >> >> thanks a lot, >> clion >> -- >> View this message in context: >> http://www.nabble.com/referring-to-data-of-previous-rows-tp25987364p25987364.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://www.nabble.com/referring-to-data-of-previous-rows-tp25987364p26004769.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.
