Computing Baseball Stats using Riak Map/Reduce
First, grab the game event files by decade from the Retrosheet archive: http://www.retrosheet.org/game.htm. Unzip them into usefully-named directories (e.g. “1950s”).
Setup Riak, then clone luwak_mr and this project, build them, and add them to Riak’s code path.
Load the Retrosheet data into Riak by attaching to the Riak console and using baseball:load_events(Directory), where Directory is the path to one of your unzipped archives (e.g. “/home/bryan/baseball/1950s”).
Compute the batting average for any player by attaching to the Riak console and using baseball:batting_average(File, PlayerID), where File is the last component of the path that you used in your load_events call (e.g. 1950s), and PlayerID is the 8-character identifier of any player (see the .ROS files in your unpacked archive, or the Retrosheet docs for information about player IDs).