Hello, I understand that the/ demean/ argument in the *ar()* function to fit an autoregressive model selects the best AR model fitted to the mean deleted observations. What is the purpose of using this demean procedure at all? Its seems silly as the post doesn't deal with R problems.... Thanks -- View this message in context: http://r.789695.n4.nabble.com/Demean-argument-in-ar-function-tp4661304.html Sent from the R help mailing list archive at Nabble.com.