Hi Laura! in your last line, you have myforecast$pred instead of my.forecast$pred Hope this helps! If that's not it, try str(my.list) str(my.forecast$pred) and check to see that they are both time series Sincerely, Erin Hodgess Associate Professor Department of Computer and Mathematical Sciences University of Houston - Downtown mailto: hodgess at gator.uhd.edu From: Laura Quinn <laura at env.leeds.ac.uk> Subject: [R] Problem with predict arima I have fitted an arima(0,0,2) model to my data, and am trying to plot a forecast for the next 15 time steps, but each time i try I am given the following error message: Error in .cbind.ts(list(...), makeNames(...), dframe = dframe, union TRUE) : non-time series not of the correct length I am calculating as follows: my.arima<-arima(my.list,order=c(0,0,2)) my.forecast<-predict(my.arima,15) ts.plot(my.list,my.forecast$pred,my.forecast$pred+2*my.forecast$se, myforecast$pred-2*my.forecast$se) my.list has 1 column and 2880 rows...I don't understand why I am getting this error message - any advice? Thanks, Laura Laura Quinn Institute of Atmospheric Science School of the Environment University of Leeds Leeds LS2 9JT