st: geocode command and google query limit

[Rüdiger Vollmeier <ruediger.vollmeier@googlemail.com>]

Dear Stata users,

I ve used the -geocode- command/.ado to locate institutions using the
fulladdress option (using number, street, city, country information).
However, for a high percentage of requests I made I got the error code
620 (Google query limit reached). I am wondering what the best
procedure is to deal with this issue.

So far I did loops over requests until a sufficiently high share of
observations were geolocated and then I discretionally geocoded the
unlocated observations using the Google web interface. However, I feel
that this procedure is highly frustrating and there might be better
procedures. Hence, the following questions popped into my mind:

1. Does anybody have a better idea how to deal with this issue (or, in
other words, how to game Google's query limit)?
2. Does anybody know how this query limit is set by Google? The number
of successful requests is decreasing in the requests requested so far
- but which which requests in the past does Google take into
consideration? What is the critical number of requests when the limit
is applied strictly?
3. Is it helpful to pause in between the requests (e.g. using the
-sleep- command)? How long should I pause it?

Thankful for any suggestions.
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