# On the probability of coincidences (but not really)

I am teaching statistics at Berkeley, where we use the Freedman, Pisani, and Purves text for many of the introductory courses. Since the text is titled Statistics, like a lot of other books, it’s referred to by the names of its authors. But “Freedman, Pisani, and Purves” is too long, so generally we call it “FPP”.

I’ve heard some people who have been around the department for a while call it “Freedman”, and indeed it does have some stylistic similarities with Freedman’s other books, such as Statistical Models: Theory and Practice. And since we’re talking about coincidences, I believe Pisani is not the CNBC correspondent of the same name, or the financial trainer, or any of various others with the same name. (Pisani’s reminiscences upon the death of Blackwell tell us that he was a lecturer at Berkeley for a long time, which seems like something these people would mention in their bios; he also got his PhD in 1970, and these two Pisanis seem younger.) While I’m on the subject, this is a wonderful, well-written book for introductory statistics classes, although sometimes it suffers from using language too well… my sense is that Kids These Days1 aren’t used to reading, and some are more comfortable with cookbook-style textbooks that will just tell them what to do. I try to break this down in my classes, but as anyone who’s taught (or learned!) knows, that’s not easy.

I also participate on the “community weblog” metafilter. There FPP refers to a “front page post”, i. e. a post made to the “front page” of the site, usually consisting of links to one or more related web sites. It would be hopelessly meta to make a front page post about Freedman, Pisani, and Purves, but I don’t have it in me. An interesting question: how many three-letter acronyms should we expect exist in my life, given that there’s a collision between two of them? By analogy with the birthday problem, the number must be at least on the order of the square root of the number of possible such acronyms, i. e. a hundred or so — surprisingly small.

The text doesn’t abbreviate “simple random sample” to SRS, but I’m tempted to sometimes in my lecture notes. But of course that conflicts with the abbreviation for “stratified random sample”. Or for “sexual reassignment surgery”.

(On titles of books: there are at least three books in my library entitled Algebra, namely those by Artin, Hungerford, and Lang. This barely counts as a coincidence, because that is the most obvious title for an algebra book.)

1. I use “Kids These Days” ironically, being still in my twenties.

## One thought on “On the probability of coincidences (but not really)”

1. Hey, I have the same 3 Algebra books. Coincidence?