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How the six-letter bird code system came about

The new coding system presented here was invented by the author for use in preparing a database of Christmas Bird Count (CBC) data. We found that using the banders' four-letter code to enter data was very frustrating, as we spent far too much time consulting the list of exceptions.

After some experimentation, we found a six-letter system to be a good tradeoff. Even though each code takes two extra keystrokes, the number of special cases went down by an order of magnitude. This greatly reduces thinking time, making the work flow more smoothly, and significantly increases the throughput measured in records per hour.

We have used these codes to enter over three million historical CBC records: all the North American and Hawaiian counts from the 1st CBC, in 1900, through the 90th CBC in 1989 (except for ten years, the 63rd-72nd counts, which were provided by Dr. Carl Bock's project at the University of Colorado). As an example, the 89th CBC, with 1523 count circles and about 115,000 records, took less than 50 hours to enter at a keying rate of about 65 words per minute. This translates to a rate of well over 2,000 records per hour.

Many refinements in this system were suggested by Greg Butcher and Jim Lowe of the Cornell Lab of Ornithology. The author greatly appreciates their contributions.


Next: Rules for the six-letter bird code system
See also: A robust bird code system: the six-letter code
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John W. Shipman, john@nmt.edu
Last updated: 1999/10/02 19:12:25
URL: http://www.nmt.edu/~shipman/z/nom/6hist.html