Monthly Archives: November 2007

Pulling the goalie

Don Elgee, a retired teacher of mathematics and computer science from Ottawa, sends the following inquiry: In hockey, when a team is down by a goal with about one minute to go, the goalie is pulled in favor of another … Continue reading

Posted in computing, games, mathematics | 6 Comments

Last name first

Saturday’s New York Times had a story by Sam Roberts about a newly released Census Bureau study of the frequency of surnames in the U.S. The Times story was mainly about the names at the top of the list, and … Continue reading

Posted in biology, mathematics, modern life | 6 Comments


I have a few questions for the complexity theorists among us. Have you ever tried to explain to your grandmother why NP is named NP? Does she get it when you say that problems labeled NP-complete are the hardest problems … Continue reading

Posted in computing | 6 Comments

A New Yorker theorem

Barry Cipra, my friend and former neighbor, and a frequent bit-player commentator, is the Talk of the Town this week. A story in The New Yorker by Lizzie Widdicombe highlights Barry’s work on the mathematics of the following calendrical problem. … Continue reading

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Above: A throbbing, wheeling mob of several thousand restless starlings, near a strip mall in Clayton, North Carolina, 27 October 2007. Below: Snow geese on maneuvers near Ashburn, Missouri, 12 November 2004. In the 1930s, Edmund Selous argued that flocking … Continue reading

Posted in biology, computing | Comments Off