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Willianl Sealy Gosset I

From Wikipedia, the free encyclopedia ..........+ , :. , William Sealy Gosset (Jun~ 13, l876-october 16, 1937) is famous William Seal~ Gosset

as a statistician, best knowd by his pen name Student and for his work on Student's t-distribution. 1

Born in Canterbury, England to Agnes Sealy Vidal and Colonel Frederic Gosset, Gosset attended Winchester College before reading chemistry and mathematics_at New College, OKford. On graduating in 1899, he joined the Dublr brewery of Arthu~ Guinness & Son.

Guinness was a progressive agro-chemical business and Gosset would apply his statistical knowledge both in the brewery and on the farm-to the selection of the best yielding varieties of barley. Gosset acquired that knowledge by study, trial and error and by spending two terms in 1906-7 in the biometric laboratory oT Karl Pearson. Gosset and Pearson had a good relationship and Pearson helped Gosset with the mathematics of his papers. Pearson helped with the 1908 papers but he had little appreciation of their importance. The papers addressed the brewer's concern with small samples, fhile the biometrician typically had hundreds of observations and saw no urgency in developing small-sample methods.

Another researcher at Guinness had previously published a paper containing trade secrets of the Guinness brewery. To prevent further disclosure of confidential information, Guinness prohibited its employees from publishing any papers regardless of the contained information. This meant that Gosset was unaQle to publish his works under his own name. He therefore used the pseudonym Student for his publications to avoid their detection by his employer. Thus his most famous achievement is now referred to as Student's t-distribution, which might otherwise have been Gosset's t-distribution.

Gosset had almost all of his papers including The probable error ofa mean published in Pearson's journal Biometrika using the pseudonym Student. However, it was R. A. Fisher who appreciated the importance of Gosset's small-sample work, after Gosset had written to him to say lam sending you a copy ofStudent's Tables as you are the only man that's ever likely to use them!. Fisher believed that Gosset had effected a "logical revolution". Ironically the t-statistic for which Gosset is famous was actually Fisher's creation. Gosset's statistic was z = tl'V(n-l). Fisher introduced the t-form because it fit in with his theory of degrees of freedom. Fisher was also responsible for the applications ofthe t-distribution to regression.

Although introduced by others, Stude~tized residuals are named in Student's honor because, like the problem that led to Student's t-distribution, the idea of ~djusting for estimated standard deviations is central to that concept.

Gosset's interest in barley cultivation led him to speculate that design of experiments should aim, not only at improving the average yield, but also at breeding varieties whose yield was insensitive (robust) to variation in soil and climate. This principle only occurs in the later thought of Fisher and then in the work of Genichi Taguchi in the 1950s.

In 1935, he left Dublin to tak(( up the position ofHead Brewer, in charge of the scientific side of production, at a new Guinness brewery at Park Royal in North West London. He died in Beaconsfield, England of a heart attack.

lof2 5/1/2010 7:57 AM

Student in 1908

Born June 13, 1876 Canterbury, Kent, England

Died October 16, 1937 (aged 61) Beaconsfield, Buckingharnshire, England

''''--.1- - --~., -~- ....... -- _ ......... J~.I.vt"'''"' ........

Gosset was a friend of both Pearson and Fisher, an achievement, for each had a massive ego and a loathing for the

other. [citation neede Gosset was a modest man who cut short an admirer with the comment that "Fisher would have

discov~red it all an w - \ I B °bJi hIs\1 () \i \ J Sa V1 Sc • ~

I ograp Y J -:.l

• The application of th law oferror to the work of the Brewery (1904, nota inte~a Prfsso Guinness) • "On the error of counting with hremacytometer". Biometrika 5 (3): 351-360. Fe ruary 1907. • "The probable error of a mean" (http://www.york.ac.uk!depts/mathsihiststat/stu ent.pdf). Biometrika 6 (1):

1-25. March 1908. doi:1 0.1093/biomet/6. 1.1 (http://dx.doi.org/l0.1093%2Fbiomet%2F6.1.1) . I http://www.york.ac.uk!depts/maths/histstat/student.pdf. . I

• "Probable error of a correlation coefficient". Biometrika 6 (2/3): 302-310. September 1908. doi: 10.1 09Blbiomet 16.2-3.302 (http://dx.doi.org/1O.l093%2Fbiomet%2F6.2-3.302) . I I

• "The distribution of the means of samples which are not drawn at random". Biometrika 7 (l/2):121G-21f· July-october 1909. doi:l 0.1 0931biomet/7.1-2.210 (http://dx.doLorg/l 0.1093%2Fbiomet%2F7. ~ -2.21 0)\.

• "An experimental determination of the probable error of Dr Spearman's correlation coefficientsl'. Biom¢trika 13 (2/3): 263-282. July 1921. doi:1O.l093/biomet/13.2-3.263 (http://dx.doi.org/l0.1093%2Fbiomef%2F13(2-3.263)

• ;'Review of Statistical Methods for Research Workers (R. A. Fisher)" (http://www.economics.s~ton.ac.~staff laldrich/fisherguide/student.htm) . Eugenics Review 18: 148-150. 1926. http://www.economics'lsoton.a~.uk!staff

laldri~h/fisherguide/student.htm. I i • "On Student's 1908 Article "The Probable Error of a Mean"(S.L.Zabell)" (http://cda.mrs.umn.edu/~jongmink

IStat2611/s1.pdf). Journal of the American Statistical Association Vol. 103, No. 481: 1-7. March 2008. http://cda.mrs.umn.edu/~jongmink/Stat2611/sl.pdf.

• 'Student's 'Collected Papers (edited by E.S. Pearson and John Wishart, with a foreword by Launce McMullen), London: Biometrika Office. (1942)

Biographies , i I

• E. S. Pearson (1990) 'Student', A Statistical Biography of William Sealy Gosset, Edited and Augmented by R. L. Plackett with the Assistance ofG. A. Barnard, Oxford: University Press.

• E. S. Pearson, "'Student' as Statistician, Biometrika Vol. 30, No. 3/4 (Jan., 1939), pp. 210-250.

External links

• Biography by Heinz Kohler (http://www.swlearning.com/quant/kohler/statlbiographical_sketches/bio12.1.html) • Tales of Statisticians by E. Bruce Brooks (http://www.umass.edu/wsp/statistics/tales/gosset.html) • Student's T Distribution (http://www-stat.stanford.edu/~naras/jsm/mensity/mensity.html)

• Earliest known uses of some of the words of mathematics: S (http://jeff560.tripod.com/s.html) under the heading of "Student's t-distribution", describes briefly how Student's z became t.

• O'Connor, John 1.; Robertson, Edmund F., "William Sealy Gosset" (http://www-history.mcs.st-andrews.ac.uk lBiographies/Gosset.html) , MacTutor History ofMathematics archive, University of St Andrews, http://www­history.mcs.st-andrews.ac.ul1Biographies/Gosset.htmi.

J

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