tornanddesperate wrote: > > Hi its me again > > I don't mean to get on your nerves, but the use of R proofs to be a bit > more complicated than envisaged. > > I would like to calculate the mean of a group of values, here > "wage_accepted". The group is determined by the stage and period, so in > the end there should be a column with the values of the wages in period 1 > stage1, period 1 stage 2, period 2 stage1... Unfortunately, I haven't much > of a clue on how to program this. Could you tell me how the function > should roughly look like – if-else, loops included or not – in the end ? >
A couple of possible approaches .... # read in your data lines <-"treatment session period stage wage_accepted type 1 1 1 1 25 low 1 1 1 1 19 low 1 1 1 1 15 low 1 1 1 2 32 high 1 1 1 2 13 low 1 1 1 2 14 low 1 1 2 1 17 low 1 1 2 1 12 low" d <- read.table(textConnection(lines), header = TRUE) closeAllConnections() # 1. using the aggregate function aggregate(d$wage_accepted, list(period=d$period, stage=d$stage), FUN=mean) # 2. using the by function by(d$wage_accepted,list(d$period,d$stage),FUN=mean) As for tutorial resources, I would recommend visiting CRAN at http://cran.r-project.org/ ... follow the "Manuals" link on the left hand side of the page. HTH Pete -- View this message in context: http://r.789695.n4.nabble.com/how-to-calculate-the-mean-of-a-group-in-a-table-tp3505986p3506024.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.
