Karl Pearson: biography of this mathematician and biostatistician

Karl Pearson has been one of the most important statesmen, despite the fact that at first he did not plan to end up being one. Actually he studied a bit of everything, going from the pure sciences, like physics, through biology, studying about law and, oddly enough, German history.

To him we owe many statistical tools that both psychologists and other science workers of health and social sciences we use for practically everything, such as the chi square or the correlation linear.

In this biography of Karl Pearson we will see the life of this great historical figure that, with their light and dark, have determined the history of all that discipline that considers itself scientific.

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Short biography of Karl Pearson

Karl Pearson was an English historian, lawyer, mathematician, biometer, teacher, and biographer.. His interests include writing about folklore, researching philosophy, learning about German culture and also following socialist theses and admiring Karl Marx a lot. But apart from all this, what stands out most about Pearson was being a contributor to the birth of the applied statistics and use it as a fundamental tool in all knowledge that is considered scientist.

Pearson's contributions to statistics as we know it today are many, the most notable being linear correlation and the χ2 method. Besides, he is considered one of the promoters of incorporating women in science and intellectual debates, knowledge at that time reserved for the male gender. However, he also has controversial aspects such as being a supporter of eugenics influenced by Francis Galton.

Early years and education

He was born as Carl Pearson, with C, on March 27, 1857 in London, England.. His family was originally from Yorkshire, upper-middle class and puritanical in tendency. His father was a lawyer, something that may have influenced Pearson's life years later when he decided to study law. Young Pearson was educated in his home until he was nine years old. After that he began studies at the University College School of London until he was sixteen.

Due to health problems he had to temporarily stop his training at school, being assigned a private tutor at home. Despite adversity, he was able to win a scholarship to the prestigious King's College, Cambridge University to study mathematics, which he would finish in 1879.

Despite coming from a fairly religious background, at the age of 22 Karl he rejected Christianity and adopted freethought interpreting it as a kind of faith but not religious. Despite being a freethinker, he preferred to distinguish his beliefs from those of traditional freethinkers.

visit to germany

After finishing his studies at Cambridge he traveled to Germany with the intention of studying physics and he metaphysics at the University of Heidelberg and, also, stepped foot in the University of Berlin, place where he studied law. But he would not only devote himself to laws and exact sciences in this period, but also to medieval history and German literature between 1879 and 1880.

In fact, His eagerness and interest in learning about the German Middle Ages made him a great acquaintance in this matter., so much so that some time later he was offered a position in Germanic studies at the University of Cambridge upon his return to England. One of his works from this period, the result of his passionate interest in Germany, is "The New Werther", greatly influenced by Johann Wolfgang von Goethe.

It is around this time that, by chance in life, his original name, Carl, became Karl at the age of 23. The reason is due to a simple typo made at the University of Heidelberg. As the young Karl Pearson was an admirer of Karl Marx, he made this small confusion a hallmark, thus acquiring the name of Karl, with K in German, the rest of his life.

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Tour of England: the Men and Women's Club

In the year 1881 he began to study law although he never became a lawyer. Later, in 1885, he obtained a position as professor of mathematics at University College where he gained a reputation as a good if somewhat unorthodox teacher. In that period he published "The Common Sense of the Exact Sciences" and "History of the Theory of Elasticity".

Karl Pearson, Apart from being a great mathematician and scientist, he was interested in ethics and the history of Christianity., in addition to considering that gender should not be an obstacle to discuss intellectual issues. For this reason, in 1885 he founded the Men and Women's Club (Club de Hombres y Mujeres), a debate forum whose purpose was to allow free discussion between both genders.

It was at the Men and Women's Club that he would meet his later wife, Maria Sharpe. With Maria he had three children, Sigrid Loetitia, Helga and Egon, and they lived happily until she passed away in 1928, the following year Karl Pearson married a colleague from the University of London, Margaret Child.

Pearson, Galton and Welton

It is in 1890, when Karl Pearson was 33 years old, when a very important event occurred in his life, life in which he had studied mathematics but had not delved into statistics still. He became interested in statistics thanks to Charles Darwin's cousin, Francis Galton., who a year earlier had published his book “Natural Inheritance”.

In 1891 he became professor of geometry at Gresham College, where he would make contact. with one of the most important zoologists of the 19th century, Walter Frank Raphael Weldon, founder of the biometrics. The relationship between Pearson and Weldon was fruitful, making Karl acquire knowledge in biometrics and evolutionary theory. Weldon was the one who introduced Pearson to Galton.

Pearson, encouraged by Weldon, became more interested in the mathematics describing the processes of heredity and evolution and, as As a result, he published a series of articles on regression analysis, correlation coefficient, as well as introducing the χ2 (chi or chi) test. square)

The relationship between Galton, Weldon and Pearson was a beautiful one, resulting in the founding of Biometrika magazine., whose anecdote behind is worth commenting on. Pearson presented a paper at the Royal Society that, despite being very well worked, was rejected by the Academy's biologists who did not like his mathematical analysis. As a result, Weldon suggested that she start his own magazine, and with Galton's help as well, the three of them founded their own magazine.

Approach to eugenics and last years

It is here where we begin to see one of the dark parts of Pearson due to the influences of Francis Galton who is considered, by many, the founder of eugenics. Galton put Pearson in charge of his office for eugenics and she joined his Biometrics Laboratory., resulting in the founding of the Department of Applied Statistics at University College.

It should be said that we cannot deny or reject Pearson's contributions for being eugenic. In his time, this current had the support of many scientists and intellectuals, in addition to applying eugenic programs in democratic countries governed by both the right and the left. However, we must not forget that Nazism made very strong use of eugenic theses and social Darwinism, advocates of artificial selection in humans to improve our species.

Admiration for Galton lasted until his death in 1911. His admiration for Galton was such that Pearson even said that Francis Galton would be the most prodigious grandson and not Charles Darwin and that he would be the most remembered of Erasmus Darwin. It was then that Karl Pearson decided to do the biography of Darwin's cousin.

The work was published in the form of three volumes that came out in 1914, 1924, and 1930. He used multiple sources for bibliography, including Francis Galton's letters, narratives, genealogies, commentaries, and photographs. This work exalted Galton's life, his work, and his personal legacy to Pearson. Pearson himself put out of his pocket so these books could be printed.

On Galton's death, Karl Pearson left part of his estate to the University of London for a research post in eugenics. Pursuant to the late mentor's wishes, Pearson incorporated the biometric lab and Galton's lab. Karl Pearson would remain in that department until his retirement in 1933, although he continued working on different projects until his death on April 27, 1936 at the age of 79.

Works by Karl Pearson

There are several texts, articles and books by Karl Pearson. As a great intellectual of his time, with a multifaceted profile touching both pure sciences and humanities, It is not surprising that among his books, mathematics, philosophy, history and religion are addressed.. Here is a list of some of his works.

• The New Werther (1880)
• The Trinity, A Nineteenth Century Passion Play (1882)
• Die Fronica (1887)
• The Ethic of Freethought (1886)
• The Grammar of Science (1892)
• On the dissection of asymmetrical frequency curves (1894)
• Skew variation in homogeneous material (1895)
• Regression, heredity and panmixia (1896)
• On the criterion that a given system of deviations from the probable in the case of a correlated system of variables is such that it can be reasonably supposed to hove arisen from random sampling (1900)
• Tables for Statisticians and Biometricians (1914)
• Tables of Incomplete Beta Function (1934)

Bibliographic references:

• Gomez Villegas, M.A. (2005) Statistical Inference, Madrid: Díaz de Santos.
• Pearson, K. (1900) On the criterion that a given system of deviations from the probable in the case of a correlated system of variables is such that it can be reasonably supposed to have arisen from random sampling, Philosophical Magazine 5 th series, 50, 157-175.
• Pearson, K. (1978) The History of Statistics in the 17th and 18th Centuries, Edited by E.S. pearson. New York: MacMillan.
• Pearson, K. (1895) Contributions to the mathematical theory of evolution, II: skew variation. Philosophical Transactions of the Royal Society of London, A, 186, 343-414.
• Pearson, K. (1896) Contributions to the mathematical theory of evolution, III: regression, heredity and panmixia, Philosophical Transactions of the Royal Society of London, A, 187, 253-318.
• Pearson, K. and Filon, L.N.G. (1898) Contributions to the mathematical theory of evolution, IV: on the probable errors of the frequency constants and on the influence of random selection on variation and correlation. Philosophical Transactions of the Royal Society of London, A, 191, 229-311.
• Stigler, S.M. (1986) The History of Statistics: The Measurement of Uncertainty before 1900, Cambridge: Belknap Harvard.