Posted on Categories Expository Writing, MathematicsTags , , , ,

Some puzzles about boxes

This article is a break from data-science, and is instead about the kind of problem you can try on the train. It is problem 70 in Bollobas’s “The art of mathematics” (though I forgot that and re-worked the problem crudely from memory when writing this article).

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One of the many irritating things about airlines is the fact that the cary-on bag restrictions are often stated as “your maximum combined linear measurement (length + width + height) must not exceed 45 inches” when they really mean your bag must fit into a 14 inch by 9 inch by 22 inch box (so they actually may not accept a 43 inch by one inch by one inch pool spear as your carry-on). The “total linear measure” seems (at first glance) “gameable,” but can (through some hairy math) at least be seen to at least be self-consistent. It turns out you can’t put a box with longer total linear measurements into a box with smaller total linear measurements.

Let’s work out why this could be problem and then why the measure works. Continue reading Some puzzles about boxes

Posted on Categories Administrativia, data scienceTags 2 Comments on Just spoke at The Berkeley R Language Beginner Study Group

Just spoke at The Berkeley R Language Beginner Study Group

Just spoke at The Berkeley R Language Beginner Study Group. Great audience, very bright. Here are my slides: StartR.pdf .