Ronald Fisher (Born on this day in history)
A foundational contributor to the field of statistics
On this day (February 17) in 1890, Ronald Fisher was born in London, England. He was a statistician and geneticist who spent most of his life in Britain before moving to Australia in his final years. During his career, he worked at The Rothamsted Experimental Station, University College London, The University of Cambridge, and The Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Adelaide, Australia.
Ronald Fisher made numerous foundational contributions to the field of statistics; here are several of the most familiar ones to statisticians:
1. Analysis of variance (ANOVA): Fisher developed the technique of ANOVA, which allows researchers to test for differences between group means. This is a very useful framework in experimental design, and it is still widely used in many scientific fields.
2. Maximum likelihood estimation (MLE): Fisher introduced the method of maximum likelihood estimation, which estimates the parameters of a statistical model by maximizing the likelihood function. MLE remains a cornerstone of modern statistical theory.
3. Fisher's exact test: He developed this statistical test to determine if there are non-random associations between two categorical variables, and this is especially useful in small sample sizes. (With large sample sizes, this test can take a long time to compute.)
3. Design of experiments: Fisher made significant advancements in experimental design (particularly the principles of randomization and blocking) to ensure valid and efficient experiments. His 1935 book "The Design of Experiments" laid out these methods, which are still key to scientific research.
4. Statistical significance and P-values: Fisher popularized the use of P-values to assess the significance of statistical results, defining the concept of statistical significance in hypothesis testing. (Unfortunately, many people misuse and misinterpret P-values today. To resolve this massive confusion, I encourage you to read the 2016 statement about P-values by the American Statistical Association - ASA.)
5. Fisher information: He introduced the concept of Fisher information, which measures the amount of information that an observable random variable carries about an unknown parameter.
6. F-distribution: Fisher introduced the F-distribution, a continuous probability distribution that arises frequently in regression analysis and ANOVA.
If you are reading my posts for the first time: I'm Eric Cai, a statistician based in Toronto, Canada. I write about statistics, communication, and career development for professionals in data & analytics. Subscribe to get my articles delivered to your inbox at 9:30 AM Eastern time on Monday to Friday.