[R] Calculating Mean

[Rui Barradas]

Hello,

Like Ivan said, you should give us a data example, the best way is to do 
it is to paste the output of ?dput in a post. If your data frame is 
named 'dat' use the following.

dput(head(dat, 50))  # paste the output of this in a post

As for the question, here is an example using ?aggregate, with fake data.


dat <- data.frame(X = rnorm(100), A = sample(8, 100, TRUE))

aggregate(X ~ A, data = dat, FUN = mean)


Hope this helps,

Rui Barradas

Em 03-06-2013 10:15, Laura Thomas escreveu:
> Hi All,
>
> Sorry about this quite basic, but I am very new to R.
>
> I have a data file which has a dependent variable (reaction time) and a couple of independent variables, one of which is coded 1-8; I want to calculate the reaction time for each of the 8 codes of the independent variable.
>
> Thanks for any help,
>
> Laura
>
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