[R] Collapsing a factor in R
I'm trying to collapse the following table along the sub-group factor. In this case, collapsing means taking the average ages within a subgroup and creating a new table. I seem to be running into trouble trying to create this new data frame. I can use the ave() function to find averages within a subgroup but how do I maintain the Group/Gender factors after collapsing? (see bottom table) Can anyone help?? Thanks in advance!! Here's the starting point (table) Age Group SubGroup Gender 12 g1 a f 32 g1 a f 81 g1 a f 63 g1 b m 24 g1 b m 24 g1 b m 70 g1 c f 82 g1 c f 71 g1 c f 61 g1 c f 25 g2 d m 29 g2 d m 43 g2 e f 17 g2 e f 42 g2 e f 55 g2 e f 52 g2 f f 19 g2 f f 12 g2 f f The following is what I'm trying to achieve (as a new dataframe) AvgAgeSubgroup Group SubgroupGender 41.67 g1 a f 37 g1 b m 71 g1 c f 27 g2 d m 39.25 g2 e f 27.67 g2 f f Can anyone help? -Scott [[alternative HTML version deleted]] __ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Re: [R] Collapsing a factor in R
Will aggregate() do what you want? -roger Scott Norton wrote: I'm trying to collapse the following table along the sub-group factor. In this case, collapsing means taking the average ages within a subgroup and creating a new table. I seem to be running into trouble trying to create this new data frame. I can use the ave() function to find averages within a subgroup but how do I maintain the Group/Gender factors after collapsing? (see bottom table) Can anyone help?? Thanks in advance!! Here's the starting point (table) Age Group SubGroup Gender 12 g1 a f 32 g1 a f 81 g1 a f 63 g1 b m 24 g1 b m 24 g1 b m 70 g1 c f 82 g1 c f 71 g1 c f 61 g1 c f 25 g2 d m 29 g2 d m 43 g2 e f 17 g2 e f 42 g2 e f 55 g2 e f 52 g2 f f 19 g2 f f 12 g2 f f The following is what I'm trying to achieve (as a new dataframe) AvgAgeSubgroup Group SubgroupGender 41.67 g1 a f 37 g1 b m 71 g1 c f 27 g2 d m 39.25 g2 e f 27.67 g2 f f Can anyone help? -Scott [[alternative HTML version deleted]] __ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html __ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
