I have data like this
aap sc
met p1 34
met p1 56
met p2 45
met p2 33
ser p1 34
ser p1 56
ser p2 45
ser p2 33
...
I want to estimate the following variances for:
sc in p1 for met
sc in p2 for met
sc between p1 and p2 for met
sc for met
sc in p1 for ser
sc in p2 for ser
sc
assuming your data is called dat, you can use:
tapply(dat$sc, INDEX=list(p=dat$p, aa=dat$aa), var)
see ?tapply and ?var
I hope this helps
Francisco
Aimin Yan wrote:
I have data like this
aap sc
met p1 34
met p1 56
met p2 45
met p2 33
ser p1 34
ser p1 56
ser p2
