Re: [R] Select random observation from a group

Hi, May be this helps: set.seed(42) indx <- with(df,tapply(seq_along(IndividualID), FamilyID,FUN=sample,1))  df[indx,] # FamilyID IndividualID DadID MomID Sex #4    1  104 0 0   2 #8    2  204   202   203   2 #or library(plyr)  ddply(df,.(FamilyID),function(x) x[w

Re: [R] Select random observation from a group

2014 10:11 a.m. To: r-help@r-project.org Subject: [R] Select random observation from a group Hello, I have a dataset with family data. For an analysis, I need to select one subject per family at random. Here is an example of what my data look like: FamilyID IndividualID DadID

[R] Select random observation from a group

Hello, I have a dataset with family data. For an analysis, I need to select one subject per family at random. Here is an example of what my data look like: FamilyID IndividualID DadIDMomID Sex 1101103 104 1 1