Thanks Michael, But I can't see the dates on the NEWS so I have no idea what changed from last version or from whichever version we actually have installed. Do you see what I mean? Thanks, Xu -- View this message in context: http://r.789695.n4.nabble.com/changelog-for-MASS-tp4034473p4040941.html Sent from the R help mailing list archive at Nabble.com.