Pearson's original paper uses both \chi and \chi^2 frequently but never spells out how to pronounce the latter. Try another question: when talking about \sigma^2 do you say "sigma-square" (which sounds rather odd) or "sigma-squared" (which sounds more natural)? If you say sigma-square, say chi-square. If you say sigma-squared, say chi-squared. For what it's worth, the multu=i-volume "Encyclopedia of Statistical Sciences", 2nd edition, uses both variants. And so does Kendal & Stuart, volume 2, 1961, although "-squared" seems to predominate.
On Sat, 19 Oct 2019 at 11:27, Dalthorp, Daniel via R-help <r-help@r-project.org> wrote: > > oh my... > > I'd like to see the statistics on it before jumping to a conclusion that > the American preference is "chi-square" and the British preference is > "chi-squared". I don't see that at all. > > ------ > In keeping with the pronunciation of x^2 and 3^2, maybe "chi-squared" makes > the most sense,. > > The "chi-square"? Because the iterated dentals in "chi-squared > distribution" and "chi-squared test" are a little cumbersome to pronounce, > an even slightly lazy pronunciation would sound like "chi-square > distribution" and "chi-square test". There's no need to write it that way > though. > > -Dan > > > > On Fri, Oct 18, 2019 at 2:28 PM Richard M. Heiberger <r...@temple.edu> wrote: > > > What a delightful question. Bill Cochran discussed this in class > > one day about 50 years ago. He said the British usage (which I think > > he said was chi-squared, > > as is consistent with the other memories in this thread) > > is what he learned and previously used. But he had been in the US for > > so long that he was now using > > the American preference (chi-square). > > > > Rich > > > > On Fri, Oct 18, 2019 at 8:51 AM Martin Maechler > > <maech...@stat.math.ethz.ch> wrote: > > > > > > As it's Friday .. > > > > > > and I also really want to clean up help files and similar R documents, > > > both in R's own sources and in my new 'DPQ' CRAN package : > > > > > > As a trained mathematician, I'm uneasy if a thing has > > > several easily confusable names, .. but as somewhat > > > humanistically educated person, I know that natural languages, > > > English in this case, are much more flexible than computer > > > languages or math... > > > > > > Anyway, back to the question(s) .. which I had asked myself a > > > couple of months ago, and already remained slightly undecided: > > > > > > The 0-th (meta-)question of course is > > > > > > 0. Is it worth using only one written form for the > > > χ² - distribution, e.g. "everywhere" in R? > > > > > > The answer is not obvious, as already the first few words of the > > > (English) Wikipedia clearly convey: > > > > > > The URL is https://en.wikipedia.org/wiki/Chi-squared_distribution > > > and the main title therefore also > > > "Chi-squared distribution" > > > > > > Then it reads > > > > > > > This article is about the mathematics of the chi-squared > > > > distribution. For its uses in statistics, see chi-squared > > > > test. For the music [...] > > > > > > > In probability theory and statistics, the chi-square > > > > distribution (also chi-squared or χ2-distribution) with k > > > > degrees of freedom is the distribution of a sum of the squares > > > > of k independent standard normal random variables. > > > > > > > The chi-square distribution is a special case of the gamma > > > > distribution and is one of the most widely used probability > > > > distributions in inferential statistics, notably in hypothesis > > > > testing [........] > > > > [........] > > > > > > So, in title and 1st paragraph its "chi-squared", but then > > > everywhere(?) the text used "chi-square". > > > > > > Undoubtedly, Wilson & Hilferty (1931) has been an important > > > paper and they use "Chi-square" in the title; > > > also Johnson, Kotz & Balakrishnan (1995) > > > see R's help page ?pchisq use "Chi-square" in the title of > > > chapter 18 and then, diplomatically for chapter 29, > > > "Noncentral χ²-Distributions" as title. > > > > > > So it seems, that historically and using prestigious sources, > > > "chi-square" to dominate (notably if we do not count "χ²" as an > > > alternative). > > > > > > Things look a bit different when I study R's sources; on one > > > hand, I find all 4 forms (s.Subject); then in the "R source > > > history", I see > > > > > > $ svn log -c11342 > > > > > ------------------------------------------------------------------------ > > > r11342 | <....> | 2000-11-14 ... > > > > > > Use `chi-squared'. > > > > > ------------------------------------------------------------------------ > > > > > > which changed 16 (if I counted correctly) cases of 'chi-square' to > > 'chi-squared'. > > > > > > I have not found any R-core internal (or public) reasoning about > > > that change, but had kept it in mind and often worked along that "goal". > > > > > > As a consequence, "statistically" speaking, much of R's own use has been > > > standardized to use "chi-squared"; but as I mentioned, I still > > > find all 4 variants even in "R base" package help files > > > (which of course I now could quite quickly change (using Emacs M-x > > grep, plus a script); > > > but > > > > > > ... "as it is Friday" ... I'm interested to hear what others > > > think, notably if you are native English (or "American" ;-) > > > speaking and/or have some extra good knowledge on such > > > matters... > > > > > > Martin Maechler > > > ETH Zurich > > > > > > ______________________________________________ > > > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > > > https://stat.ethz.ch/mailman/listinfo/r-help > > > PLEASE do read the posting guide > > http://www.R-project.org/posting-guide.html > > > and provide commented, minimal, self-contained, reproducible code. > > > > ______________________________________________ > > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > > https://stat.ethz.ch/mailman/listinfo/r-help > > PLEASE do read the posting guide > > http://www.R-project.org/posting-guide.html > > and provide commented, minimal, self-contained, reproducible code. > > > > > -- > Dan Dalthorp, PhD > USGS Forest and Rangeland Ecosystem Science Center > Forest Sciences Lab, Rm 311 > 3200 SW Jefferson Way > Corvallis, OR 97331 > ph: 541-750-0953 > ddalth...@usgs.gov > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
