st: may not use time-series operators on string variables

["Lee Chuntao" <chtl@econ.hku.hk>]

Hi Listers

   In my dataset there is a variable v1, which is a string variable. I try to use l.v1, after i set the time variable (eg, tsset time). I don't know why stata do not permit timeseries operators on string variables, it seems not reasonable for the lag or lead operators, beyond the difference operators

i wonder if there is some sort way so that i can use the laged string variable?


thanks

chuntao 

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