open-ended questions - a gold mine of data

That's not too hard. Just pick a constant (e.g.: say, all the editors with more than 1000 edits, or all the editors who thought that complexity was a factor in why they left) and pick a random sample of 20 surveys. From those 20 surveys, aggregate their answers about their best/worst experience, and the "miscellaneous question" at the end. From there, we could easily look for common themes, as well as significant differences.

Randomran23:18, 31 January 2010