From: Frank <rggefrm_at_ucl.ac.uk>

Date: Sun 01 Oct 2006 - 11:15:58 GMT

* >
*

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 and provide commented, minimal, self-contained, reproducible code. Received on Sun Oct 01 22:16:19 2006

Date: Sun 01 Oct 2006 - 11:15:58 GMT

I have some problems with the aggregate function.

I used the aggegate function to obtain the mean in V1 and V2 over the
grouping variable

Time and Day

aggregate(frame[,c(-1)],list(frame$Day,frame$Time),mean)

Group.1 Group.2 Time V1 V2 1 M 0 0 4.000000 NA 2 T 0 0 4.000000 45 3 M 1 1 NA 5 4 T 1 1 4.333333 2

My problem is now that I do not obtain a 'mean' for Day=M/Time=0 and Day=M/Time=1,

because aggregate ignores all values for a grouping variable if NA occurs.

I'm now hoping for some help so that the mean is still calculated in this group.

My table should look like:

aggregate(frame[,c(-1)],list(frame$Day,frame$Time),mean)

Group.1 Group.2 Time V1 V2 1 M 0 0 4.000000 2 2 T 0 0 4.000000 45 3 M 1 1 10 5 4 T 1 1 4.333333 2

* >
*

I hope my description makes sense and appreciate any help.

Yours

Frank

[[alternative text/enriched version deleted]]

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 and provide commented, minimal, self-contained, reproducible code. Received on Sun Oct 01 22:16:19 2006

Archive maintained by Robert King, hosted by
the discipline of
statistics at the
University of Newcastle,
Australia.

Archive generated by hypermail 2.1.8, at Sun 01 Oct 2006 - 13:30:07 GMT.

*
Mailing list information is available at https://stat.ethz.ch/mailman/listinfo/r-help.
Please read the posting
guide before posting to the list.
*