Ronald Fisher

Sir Ronald Fisher
File:R. A. Fischer.jpg
Born	(1890-02-17)17 February 1890 East Finchley, London, England
Died	29 July 1962(1962-07-29) (aged 72) Adelaide, South Australia
Nationality	British
Alma mater	University of Cambridge
Known for	Fisher's fundamental theorem Maximum likelihood Fisher information Analysis of variance The Fisher-Kolmogorov equation Fisher's equation Fisher's geometric model Coining the term "null hypothesis" Fiducial inference Fisher's exact test Fisher's principle Fisherian runaway The F-distribution
Awards	Fellow of the Royal Society (1929) Royal Medal (1938) Guy Medal in Gold (1946) Copley Medal (1955) Linnean Society of London's Darwin–Wallace Medal (1958)
Scientific career
Fields	Statistics, Genetics, and Evolutionary biology
Institutions	Rothamsted Experimental Station University College London Cambridge University University of Adelaide, and CSIRO
Academic advisors	Sir James Jeans and F. J. M. Stratton
Doctoral students	C. R. Rao, D. J. Finney, and Walter Bodmer
Notes
He was the father-in-law of George E. P. Box.

Not to be confused with Irving Fisher or Michael Fisher.

Sir Ronald Aylmer Fisher FRS (17 February 1890 – 29 July 1962), known as R.A. Fisher, was an English statistician, evolutionary biologist, mathematician, geneticist, and eugenicist. Fisher is known as one of the chief architects of the modern evolutionary synthesis, where he outlined Fisher's principle as well as the Fisherian runaway theory of sexual selection, for his important contributions to statistics, including the analysis of variance (ANOVA), method of maximum likelihood, fiducial inference, and the derivation of various sampling distributions, and for being one of the three principal founders of population genetics. Anders Hald called him "a genius who almost single-handedly created the foundations for modern statistical science", while Richard Dawkins named him "the greatest biologist since Darwin".

Biography

Early life

Fisher was born in East Finchley in London, England, to George and Katie Fisher. His father was a successful auctioneer and fine arts dealer at one time. He had a happy childhood, being doted on by three older sisters, an older brother, and his mother, but she died from acute peritonitis when he was 14. His father lost his business in several ill-considered transactions only 18 months later.

From 1896 until 1904 the family lived at Inverforth House in north London, on the edge of Hampstead Heath, where English Heritage installed a blue plaque in 2002 to mark Ronald Fisher's boyhood residency.

Although Ronald Fisher had quite poor eyesight, he was a precocious student, winning the Neeld Medal (a competitive essay in mathematics) at Harrow School at the age of 16. Because of his poor eyesight, he was tutored in mathematics without the aid of paper and pen, which developed his ability to visualize problems in geometrical terms, without contributing to his interest in writing proper derivations of mathematical solutions, especially proofs. He amazed his peers with his ability to conjecture mathematical solutions without justifying his conclusions by showing intermediate steps. He also developed a strong interest in biology, and especially evolutionary biology.

In 1909, he won a scholarship to the Gonville and Caius College, Cambridge. There he formed many friendships and became enthralled with the heady intellectual atmosphere. At Cambridge, Fisher learned of the newly rediscovered theory of Mendelian genetics. He saw biometry and its growing corpus of statistical methods as a potential way to reconcile the discontinuous nature of Mendelian inheritance with continuous variation and gradual evolution. However, his foremost concern was eugenics, which he saw as a pressing social as well as scientific issue that encompassed both genetics and statistics.

Fisher as a steward at the First International Eugenics Conference in 1912

In 1911, Fisher was involved in the forming of the University of Cambridge Eugenics Society with John Maynard Keynes, R. C. Punnett, and Horace Darwin (the son of Charles Darwin). This group was active, and it held monthly meetings, often featuring addresses by leaders of mainstream eugenics organizations, such as the Eugenics Education Society of London, founded by Charles Darwin's half-cousin, Francis Galton in 1909.

Close to Fisher's graduation in 1912, his tutor told his student that—despite his enormous aptitude for scientific work and his mathematical potential—his disinclination to show calculations or to prove propositions rendered him unsuited for a career in applied mathematics, which required greater thoroughness. His tutor gave him a "lukewarm" recommendation, stating that if Fisher "had stuck to the ropes he would have made a first-class mathematician, but he would not."

After his graduation, Fisher was eager to join the British Army in anticipation of the entry of Great Britain into World War I. However, he failed the medical examinations repeatedly because of his poor eyesight. Over the next six years, he worked as a statistician for the City of London. For part of his war work, he took up teaching physics and mathematics at a sequence of public schools, including Bradfield College in Berkshire, as well as aboard H.M. Training Ship Worcester. Major Leonard Darwin (another son of Charles Darwin) and an unconventional and vivacious friend he called Gudruna were almost his only contacts with his Cambridge circle. They sustained him through this difficult period.

A bright spot in his life then was his marriage to Gudruna's sister Eileen Guinness. They were married in 1917 when she was only 17 years old. With her sister's help, he set up a subsistence farming operation on the Bradfield estate, where they had a large garden and raised animals, learning to make do on very little. They lived through the rest of the war without using their food coupons.

During this period, Fisher started writing book reviews for the Eugenic Review and gradually increased his interest in genetic and statistical work. He volunteered to undertake all such reviews for the journal, and was hired to a part-time position by Major Darwin. He published several articles on biometry during this period, including the ground-breaking paper "The Correlation Between Relatives on the Supposition of Mendelian Inheritance", written in 1916 and published in 1918. This paper laid foundation for what came to be known as biometrical genetics, and it introduced the methodology of the analysis of variance, which was a considerable advance over the correlation methods used earlier. This paper showed that the inheritance of traits measurable by real values (i.e., continuous or dimensional traits) is consistent with Mendelian principles. This forms the basis of the genetics of complex trait inheritance and mitigated debates between biometricians and Mendelians, and the compatibility of particulate inheritance with natural selection. In this paper was also the first use of the term "variance" in statistics.

After the end of World War I, Fisher went looking for a new job in low hopes, calling himself "an egregious failure in two professions" as a commercial statistician and as a teacher. He was offered a position at the Galton Laboratory led by Karl Pearson, the founder of mathematical statistics in Great Britain. Because he saw the developing rivalry with Pearson as a professional obstacle, however, he accepted a temporary job instead as a statistician with a small agricultural station in the countryside in 1919.

Stained glass window in the dining hall of Caius College, in Cambridge, commemorating Ronald Fisher and representing a Latin square.

Early professional years

In 1919, Fisher started work at Rothamsted Experimental Station in Harpenden, Hertfordshire, England. Here he started a major study of the extensive collections of data recorded over many years. This resulted in a series of reports under the general title Studies in Crop Variation. This began a period of great productivity. Over the next seven years, he pioneered the principles of the design of experiments and elaborated his studies of analysis of variance. He furthered his studies of the statistics of small samples. Perhaps even more important, he began his systematic approach of the analysis of real data as the springboard for the development of new statistical methods. He developed computational algorithms for analyzing data from his balanced experimental designs. In 1925, this work resulted in the publication of his first book, Statistical Methods for Research Workers. This book went through many editions and translations in later years, and it became the standard reference work for scientists in many disciplines. In 1935, this book was followed by The Design of Experiments, which was also widely used.

In addition to analysis of variance, Fisher named and promoted the method of maximum likelihood estimation. Fisher also originated the concepts of sufficiency, ancillary statistics, Fisher's linear discriminator and Fisher information. His article On a distribution yielding the error functions of several well known statistics (1924) presented Pearson's chi-squared test and William Gosset's t in the same framework as the Gaussian distribution, and his own parameter in the analysis of variance Fisher's z-distribution (more commonly used decades later in the form of the F distribution). These contributions made him a major figure in 20th century statistics. He was a prominent opponent of Bayesian statistics, and was even the first to use the term "Bayesian".

His work on the theory of population genetics also made him one of the three great figures of that field, together with Sewall Wright and J. B. S. Haldane, and as such was one of the founders of the neo-Darwinian modern evolutionary synthesis. In addition to founding modern quantitative genetics with his 1918 paper, he was the first to use diffusion equations to attempt to calculate the distribution of gene frequencies among populations. He pioneered the estimation of genetic linkage and gene frequencies by maximum likelihood methods, and wrote early papers on the wave of advance of advantageous genes and on clines of gene frequency. His 1950 paper on gene frequency clines is notable as the first application of a computer, the EDSAC, to biology.

His ground-breaking book The Genetical Theory of Natural Selection was started in 1928 and published in 1930. He developed ideas on sexual selection, including Fisher's principle and the Fisherian runaway]], mimicry and the evolution of dominance. He famously showed that the probability of a mutation increasing the fitness of an organism decreases proportionately with the magnitude of the mutation. He also proved that larger populations carry more variation so that they have a larger chance of survival. It was in this book that he set forth the foundations of what was to become known as population genetics. The book was reviewed, among others, by physicist Charles Galton Darwin, a grandson of Charles Darwin's, and following publication of his review, C. G. Darwin sent Fisher his copy of the book, with notes in the margin. The marginal notes became the food for a correspondence running at least three years. Fisher's book also had a major influence on the evolutionary biologist W. D. Hamilton and the development of his later theories on the genetic basis for the existence of kin selection.

Fisher had a long and successful collaboration with E. B. Ford in the field of ecological genetics. The outcome of this work was the general recognition that the force of natural selection was often much stronger than had been appreciated before, and that many ecogenetic situations (such as polymorphism) were not selectively neutral, but were maintained by the force of selection. Fisher was the original author of the idea of heterozygote advantage, which was later found to play a frequent role in genetic polymorphism. The discovery of indisputable cases of natural selection in nature was one of the main strands in the modern evolutionary synthesis.

His later years

Fisher received the recognition of his peers in 1929 when he was inducted into the Royal Society. His fame grew and he began to travel more and lecture to wider circles. In 1931, he spent six weeks at the Statistical Laboratory at Iowa State College in Ames, Iowa. He gave three lectures per week on his work, and he met many of the active American statisticians, including George W. Snedecor. He returned to Iowa State again for another visit in 1936.

In 1933 he left Rothamsted to become a Professor of Eugenics at the University College London. In 1937, he visited the Indian Statistical Institute in Calcutta, which at the time consisted of one part-time employee, P. C. Mahalanobis. He visited there often in later years, encouraging its development. He was the guest of honour at its 25th anniversary in 1957 when it had grown to 2000 employees.

In 1939, when World War II broke out for the British Empire, the University tried to dissolve the eugenics department, and it ordered all of the animals destroyed. Fisher fought back, but then he was dispatched back to Rothamsted with a much reduced staff and resources. He was unable to find any really suitable war work, and though he kept very busy with various small projects, he became discouraged of any real progress. His marriage disintegrated. His oldest son George, an aviator, was killed in combat.

In 1943, Fisher was offered the Balfour Chair of Genetics at the University of Cambridge, his alma mater. During the war, this department was almost destroyed, but the University promised him that he would be charged with rebuilding it after the war. Fisher accepted this offer, but the promises were largely unfulfilled, and the department grew very slowly. A notable exception was the recruitment in 1948 of the Italian researcher Cavalli-Sforza, who established a one-man unit of bacterial genetics. He continued his work on mouse chromosome mapping—breeding the mice in laboratories in his own house— and other projects. These culminated in the publication in 1949 of The Theory of Inbreeding. In 1947, Fisher cofounded the journal Heredity: An International Journal of Genetics with Cyril Darlington.

He opposed the UNESCO Statement of Race. He believed that evidence and everyday experience showed that human groups differ profoundly "in their innate capacity for intellectual and emotional development" and concluded that the "practical international problem is that of learning to share the resources of this planet amicably with persons of materially different nature", and that "this problem is being obscured by entirely well-intentioned efforts to minimize the real differences that exist". The revised statement titled "The Race Concept: Results of an Inquiry" (1951) was accompanied by Fisher's dissenting commentary.

Fisher eventually received many awards for his work, and he was dubbed a Knight Bachelor by Queen Elizabeth II in 1952. He was also awarded the Linnean Society of London's prestigious Darwin–Wallace Medal in 1958.

Memorial plaque over remains of Ronald Aylmer Fisher, lectern-side aisle of St Peter's Cathedral, Adelaide

An inveterate pipe-smoker, Fisher was opposed to the conclusions of Richard Doll and Austin Bradford Hill that smoking causes lung cancer. He compared the correlations in their papers to a correlation between the import of apples and the rise of divorce in order to show that correlation does not imply causation. To quote his biographers Yates and Mather, "It has been suggested that the fact that Fisher was employed as consultant by the tobacco firms in this controversy casts doubt on the value of his arguments. This is to misjudge the man. He was not above accepting financial reward for his labours, but the reason for his interest was undoubtedly his dislike and mistrust of puritanical tendencies of all kinds; and perhaps also the personal solace he had always found in tobacco."

After retiring from the University of Cambridge in 1957, Fisher emigrated, and he spent some time as a senior research fellow at the Australian CSIRO in Adelaide, South Australia. He died in Adelaide in 1962. His remains were interred within St Peter's Anglican Cathedral, North Adelaide

Personality and beliefs

Fisher was noted for his loyalty to his friends. Once he had formed a favourable opinion of any man, he was loyal to a fault. A similar sense of loyalty bound him to his culture. He was a patriot, a member of the Church of England, politically conservative, and a scientific rationalist. Much sought after as a brilliant conversationalist and dinner companion, he very early on developed a reputation for carelessness in his dress and, sometimes, his manners. In later years he was the archetype of the absent-minded professor.

He knew the scriptures well and H. Allen Orr describes him in the Boston Review as a "deeply devout Anglican who, between founding modern statistics and population genetics, penned articles for church magazines". But he was not dogmatic in his religious beliefs. In a 1955 broadcast on Science and Christianity, he said:

The custom of making abstract dogmatic assertions is not, certainly, derived from the teaching of Jesus, but has been a widespread weakness among religious teachers in subsequent centuries. I do not think that the word for the Christian virtue of faith should be prostituted to mean the credulous acceptance of all such piously intended assertions. Much self-deception in the young believer is needed to convince himself that he knows that of which in reality he knows himself to be ignorant. That surely is hypocrisy, against which we have been most conspicuously warned.

Fisher was an ardent promoter of eugenics, which also stimulated and guided much of his work in the genetics of humans. The last third of his book The Genetical Theory concerned the applications of these ideas to humans, and presented the data available at that time. He presented a theory that attributed the decline and fall of civilizations to its arrival at a state where the fertility of the upper classes is forced down. Using the census data of 1911 for Britain, he showed that there was an inverse relationship between fertility and social class. This was partly due, he believed, to the rise in social status of families who were not capable of producing many children but who rose because of the financial advantage of having a small number of children. Therefore he proposed the abolition of the economic advantage of small families by instituting subsidies (he called them allowances) to families with larger numbers of children, with the allowances proportional to the earnings of the father. He himself had two sons and six daughters. According to Yates and Mather, "His large family, in particular, reared in conditions of great financial stringency, was a personal expression of his genetic and evolutionary convictions."

Between 1929 and 1934 the Eugenics Society also campaigned hard for a law permitting sterilization on eugenic grounds. They believed that it should be entirely voluntary, and a right, not a punishment. They published a draft of a proposed bill, and it was submitted to Parliament. Although it was defeated by a 2:1 ratio, this was viewed as progress, and the campaign continued. Fisher played a major role in this movement, and served in several official committees to promote it. In 1934, Fisher moved to increase the power of scientists within the Eugenics Society, but was ultimately thwarted by members with an environmentalist point of view, and he, along with many other scientists, resigned.

See also

• Analysis of variance
• Fisher information (often used as a Fisher matrix)
• Fisher's equation (also known as the Fisher–Kolmogorov equation, whose solution is a Fisherian wave of advance)
• Fisher's exact test
• Fisher's Linear Discriminant
• Fisher's geometric model
• Fisher's inequality
• Fisher's iris
• Fisher's method for combining independent tests of significance
• Fisher's permutation test
• Fisher's theory of the evolution of the sex ratio
• Fisher's z-distribution
• Fisher kernel
• Fisherian runaway
• Fisher–Bingham distribution
• Fisher–Tippett distribution
• Fisher–Yates shuffle
• Behrens–Fisher problem
• Inverse probability
• R. A. Fisher Lectureship
• von Mises–Fisher distribution

Notes

• Aldrich, John (1997). "R.A. Fisher and the making of maximum likelihood 1912–1922". Statistical Science. 12 (3): 162–176. doi:10.1214/ss/1030037906.
• Box, Joan Fisher (1978) R. A. Fisher: The Life of a Scientist, New York: Wiley, ISBN 0-471-09300-9.
• William H. Kruskal: "The significance of Fisher: A review of R. A. Fisher. The Life of a Scientist, by Joan Fisher Box," Journal of the American Statistical Association, 75 (1980), 1019–1030.
• David Howie, "Interpreting Probability: Controversies and Developments in the Early Twentieth Century" (Cambridge University Press, 2002)
• Salsburg, David (2002) The Lady Tasting Tea: How Statistics Revolutionized Science in the Twentieth Century, ISBN 0-8050-7134-2

Bibliography

Main article: Ronald Fisher bibliography

A selection from Fisher's 395 articles

These are available on the University of Adelaide website:

• "Frequency distribution of the values of the correlation coefficient in samples from an indefinitely large population". Biometrika. 10: 507–521. 1915. doi:10.1093/biomet/10.4.507.
• "The correlation between relatives on the supposition of Mendelian inheritance". Trans. Roy. Soc. Edinb. 52: 399–433. 1918. doi:10.1017/s0080456800012163. It was in this paper that the word variance was first introduced into probability theory and statistics.
• "On the mathematical foundations of theoretical statistics" (PDF). Philosophical Transactions of the Royal Society, A. 222: 309–368. 1922. doi:10.1098/rsta.1922.0009.
• "On the dominance ratio". Proc. Roy. Soc. Edinb. 42: 321–341. 1922.
• "On a distribution yielding the error functions of several well known statistics". Proc. Int. Cong. Math. 2: 805–813. 1924.
• "Theory of statistical estimation" Proceedings of the Cambridge". Philosophical Society. 22: 700–725. 1925. doi:10.1017/S0305004100009580.
• "Applications of Student's distribution" (PDF). Metron. 5: 90–104. 1925.
• "The arrangement of field experiments". J. Min. Agric. G. Br. 33: 503–513. 1926.
• "The general sampling distribution of the multiple correlation coefficient". Proceedings of Royal Society, A. 121: 654–673. 1928. doi:10.1098/rspa.1928.0224.
• "Two new properties of mathematical likelihood". Proceedings of Royal Society, A. 144: 285–307. 1934. doi:10.1098/rspa.1934.0050.

Books by Fisher

Full publication details are available on the University of Adelaide website:

• Statistical Methods for Research Workers (1925) ISBN 0-05-002170-2.
• The Genetical Theory of Natural Selection (1930) ISBN 0-19-850440-3.
• The Design of Experiments (1935) ISBN 0-02-844690-9
• The use of multiple measurements in taxonomic problems (in Annals of Eugenics 7/1936)
• Statistical tables for biological, agricultural and medical research (1938, coauthor:Frank Yates)
• The theory of inbreeding (1949) ISBN 0-12-257550-4, ISBN 0-05-000873-0
• Contributions to mathematical statistics, John Wiley, (1950)
• Statistical methods and scientific inference (1956) ISBN 0-02-844740-9
• Collected Papers of R.A. Fisher (1971–1974). Five Volumes. University of Adelaide.

Biographies of Fisher

• Box, Joan Fisher (1978) R. A. Fisher: The Life of a Scientist, New York: Wiley, ISBN 0-471-09300-9. Preface

Secondary literature

• Edwards, A.W.F., 2005, "Statistical methods for research workers" in Grattan-Guinness, I., ed., Landmark Writings in Western Mathematics. Elsevier: 856–70.

External links

• O'Connor, John J.; Robertson, Edmund F., "Ronald Fisher", MacTutor History of Mathematics Archive, University of St Andrews
• A Guide to R. A. Fisher by John Aldrich
• Earliest Known Uses of Some of the Words of Mathematics for Fisher’s contribution to the language of statistics
• University of Adelaide Library for bibliography, biography, 2 volumes of correspondence and many articles
• Classics in the History of Psychology for the first edition of Statistical Methods for Research Workers
• A collection of Fisher quotations compiled by A. W. F. Edwards