st: how can I group airport markets

[dluo1@uci.edu]

I have a large dataset on flights with information about origins and
destinations.
For example: origin - destination
             LAX    -    MIA
             LAX    -    MIA
             MIA    -    LAX
             MIA    -    LAX
             MIA    -    LAX
             LAS    -    LAX
             LAX    -    LAS
             ...         ...
How can I group LAX-MIA and MIA-LAX into the same market? If I use
egen market = group (origin destination), they will be grouped into 2
different markets. Another way is to sort the data into the same origins
to the same destinations, but I don't know how to do that either.
For example: origin - destination
             LAX    -    MIA
             LAX    -    MIA
             LAX    -    MIA
             LAX    -    MIA
             LAX    -    MIA
             LAX    -    LAS
             LAX    -    LAS
             ...         ...
Thanks!


Dan Luo
PhD in Economics
University of California, Irvine


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