Thank you all for the help. After I used proper subsetting, it all worked fine. And yes, I am open to receiving a prize for the most ancient version of R in use... Best, alina -- View this message in context: http://r.789695.n4.nabble.com/problem-with-xyplot-tp3391822p3398070.html Sent from the R help mailing list archive at Nabble.com.