On Wed, 12 Jan 2011, [big5] ������ ������ wrote: When you choose "/Variable/X-12-ARIMA analysis" in gretl, an X-12-ARIMA spec file is created for the variable in question. It's possible to grab and modify this file but it may not be easy to find, on MS Windows in particular. However, in current CVS gretl and snapshots (see http://gretl.sourceforge.net/win32/ ) there's an easier mechanism. Now if you do "/Variable/X-12-ARIMA analysis" you get the option of having gretl open the spec file in an editor window. (The exact option text is "Make X-12-ARIMA command file".) From there you can modify it and save it to whatever location you like. Allin Cottrell