I start everyday by doing a crossword puzzle, and I spend most of each day working on statistics (including supporting HBX CORe’s Business Analytics course). So I was excited when fellow crossword and data lover Saul Pwanson starting compiling a database of crossword puzzles published in various venues since 2003.A couple of weeks ago, puzzlemaker Ben Tausig (who edits the wonderful American Value crossword) noticed something interesting about some of the grids. A statistical analysis confirmed his suspicions: a significant number of puzzles published in USA Today or syndicated by Universal Crossword appeared to have been plagiarized. Interestingly, both the USA Today puzzle and Universal are edited by the same person, Timothy Parker.

Regular solvers know that it’s not unusual to see a specific word show up in multiple puzzles, even words like ETUI or ANILE that rarely show up anywhere else. However, the USA Today and Universal puzzles often contained long phrases that had appeared in previous puzzles. In some cases, almost the entire grid was identical to an earlier puzzle. Overall, more than one in six USA Today puzzles contained 25% or more material that had been published elsewhere. So did more than one in twenty of the Universal puzzles. For comparison, less than one in one thousand New York Times crosswords matched other puzzles that closely.

So far Parker, who is known as the most prolific editor in the crossword world, has denied any wrongdoing. However, the scandal continues to gain steam. Even the normally conflict-averse Will Shortz (editor of the New York Times crossword) has called this “an obvious case of plagiarism.” Interestingly, Parker has taken a sabbatical while his employer, Universal Uclick, investigates.

To learn more about the scandal and how crossword puzzles work, check out this great article by FiveThirtyEight: http://fivethirtyeight.com/features/a-plagiarism-scandal-is-unfolding-in-the-crossword-world/