Hi,

Hopefully a simple question for you. I have a large data set on transactions, and I need to identify (and at some point remove) observations where the variable Postcode occurs only once. The data can be represented by the small example below:

Code:
* Example generated by -dataex-. To install: ssc install dataex
clear
input long Price str1 Postcode
    40000 "A"
   325000 "B"
 54325345 "C"
     4523 "D"
 73655235 "E"
    67547 "A"
356456367 "C"
   525423 "D"
  3456254 "F"
    34563 "H"
   325234 "E"
    63562 "H"
   235426 "G"
end
In this case, I'd like to create an indicator variable equal to 1 when Postcode is B, F or G. Thanks for your help.

Jack