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Samuel S. Wilks
Samuel Stanley Wilks (June 17, 1906 – March 7, 1964) was an American mathematician and academic who played an important role in the development of mathematical statistics, especially in regard to practical applications. Early life and education Wilks was born in Little Elm, Texas and raised on a farm. He studied Industrial Arts at the North Texas State Teachers College in Denton, Texas, obtaining his bachelor's degree in 1926. He received his master's degree in mathematics in 1928 from the University of Texas. He obtained his Ph.D. at the University of Iowa under Everett F. Lindquist; his thesis dealt with a problem of statistical measurement in education, and was published in the ''Journal of Educational Psychology''. Career Wilks became an instructor in mathematics at Princeton University in 1933; in 1938 he assumed the editorship of the journal '' Annals of Mathematical Statistics'' in place of Harry C. Carver. Wilks assembled an advisory board for the journal that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Little Elm, Texas
Little Elm is a city in Denton County, Texas, United States, and a part of the Dallas–Fort Worth metroplex. It is an extended suburb of Denton; its population was 46,453 as of the 2020 census. In 2000, the census population was at 3,646. By the 2010 census, the city total had jumped to 25,898, making Little Elm one of the fastest-growing municipalities by percentage in Texas since 2000. History Little Elm was established along Lewisville Lake by C.C. "Kit" King, son of John and Delilah King, in 1844. King named the community after the creek banks where it was located. King helped organize mail service for the area and in 1852 was named the postmaster of Denton County's first post office. The population was very low throughout the first half of the 20th century but in 1966 was able to officially incorporate. The first official census for the town came in 1970 which recorded 363 persons. Geography Little Elm is generally located along the northern and eastern shores of Lewis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Educational Psychology
The ''Journal of Educational Psychology'' is a peer-reviewed academic journal that was established in 1910 and covers educational psychology. It is published by the American Psychological Association. The current editor-in-chief is Steve Graham (Arizona State University). The journal publishes original psychological research on education at all ages and educational levels, as well as occasional theoretical and review articles deemed of particular importance. According to the ''Journal Citation Reports'', the journal has a 2020 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as i ... of 5.805. The journal has implemented the Transparency and Openness Promotion (TOP) Guidelines. The TOP Guidelines provide structure to research planning and reporting and aim to make research ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Probability Distribution
In probability theory and statistics, a probability distribution is the mathematical function that gives the probabilities of occurrence of different possible outcomes for an experiment. It is a mathematical description of a random phenomenon in terms of its sample space and the probabilities of events (subsets of the sample space). For instance, if is used to denote the outcome of a coin toss ("the experiment"), then the probability distribution of would take the value 0.5 (1 in 2 or 1/2) for , and 0.5 for (assuming that the coin is fair). Examples of random phenomena include the weather conditions at some future date, the height of a randomly selected person, the fraction of male students in a school, the results of a survey to be conducted, etc. Introduction A probability distribution is a mathematical description of the probabilities of events, subsets of the sample space. The sample space, often denoted by \Omega, is the set of all possible outcomes of a random phe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Walter Shewhart
Walter Andrew Shewhart (pronounced like "shoe-heart"; March 18, 1891 – March 11, 1967) was an American physicist, engineer and statistician, sometimes known as the ''father of statistical quality control'' and also related to the Shewhart cycle. W. Edwards Deming said of him: As a statistician, he was, like so many of the rest of us, self-taught, on a good background of physics and mathematics. Born in New Canton, Illinois to Anton and Esta Barney Shewhart, he attended the University of Illinois at Urbana–Champaign before being awarded his doctorate in physics from the University of California, Berkeley in 1917. He married Edna Elizabeth Hart, daughter of William Nathaniel and Isabelle "Ibie" Lippencott Hart on August 4, 1914 in Pike County, Illinois. Work on industrial quality Bell Telephone’s engineers had been working to improve the reliability of their transmission systems. In order to impress government regulators of this natural monopoly with the high quality of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Tukey
John Wilder Tukey (; June 16, 1915 – July 26, 2000) was an American mathematician and statistician, best known for the development of the fast Fourier Transform (FFT) algorithm and box plot. The Tukey range test, the Tukey lambda distribution, the Tukey test of additivity, and the Teichmüller–Tukey lemma all bear his name. He is also credited with coining the term 'bit' and the first published use of the word 'software'. Biography Tukey was born in New Bedford, Massachusetts in 1915, to a Latin teacher father and a private tutor. He was mainly taught by his mother and attended regular classes only for certain subjects like French. Tukey obtained a BA in 1936 and MSc in 1937 in chemistry, from Brown University, before moving to Princeton University, where in 1939 he received a PhD in mathematics after completing a doctoral dissertation titled "On denumerability in topology". During World War II, Tukey worked at the Fire Control Research Office and collaborated wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Likelihood-ratio Test
In statistics, the likelihood-ratio test assesses the goodness of fit of two competing statistical models based on the ratio of their likelihoods, specifically one found by maximization over the entire parameter space and another found after imposing some constraint. If the constraint (i.e., the null hypothesis) is supported by the observed data, the two likelihoods should not differ by more than sampling error. Thus the likelihood-ratio test tests whether this ratio is significantly different from one, or equivalently whether its natural logarithm is significantly different from zero. The likelihood-ratio test, also known as Wilks test, is the oldest of the three classical approaches to hypothesis testing, together with the Lagrange multiplier test and the Wald test. In fact, the latter two can be conceptualized as approximations to the likelihood-ratio test, and are asymptotically equivalent. In the case of comparing two models each of which has no unknown parameters, use o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wilks' Theorem
In statistics Wilks' theorem offers an asymptotic distribution of the log-likelihood ratio statistic, which can be used to produce confidence intervals for maximum-likelihood estimates or as a test statistic for performing the likelihood-ratio test. Statistical tests (such as hypothesis testing) generally require knowledge of the probability distribution of the test statistic. This is often a problem for likelihood ratios, where the probability distribution can be very difficult to determine. A convenient result by Samuel S. Wilks says that as the sample size approaches \infty, the distribution of the test statistic -2 \log(\Lambda) asymptotically approaches the chi-squared (\chi^2) distribution under the null hypothesis H_0. Here, \Lambda denotes the likelihood ratio, and the \chi^2 distribution has degrees of freedom equal to the difference in dimensionality of \Theta and \Theta_0, where \Theta is the full parameter space and \Theta_0 is the subset of the parameter space asso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unit-weighted Regression
In statistics, unit-weighted regression is a simplified and robust version ( Wainer & Thissen, 1976) of multiple regression analysis where only the intercept term is estimated. That is, it fits a model :\hat = \hat(\mathbf) = \hat + \sum_i x_i where each of the x_i are binary variables, perhaps multiplied with an arbitrary weight. Contrast this with the more common multiple regression model, where each predictor has its own estimated coefficient: :\hat = \hat(\mathbf) = \hat + \sum_i \hat_i x_i In the social sciences, unit-weighted regression is sometimes used for binary classification, i.e. to predict a yes-no answer where \hat < 0 indicates "no", "yes". It is easier to interpret than multiple linear regression (known as in the classification case). Unit ...
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Office Of Naval Research
The Office of Naval Research (ONR) is an organization within the United States Department of the Navy responsible for the science and technology programs of the U.S. Navy and Marine Corps. Established by Congress in 1946, its mission is to plan, foster, and encourage scientific research to maintain future naval power and preserve national security. It carries this out through funding and collaboration with schools, universities, government laboratories, nonprofit organizations, and for-profit organizations, and overseeing the Naval Research Laboratory, the corporate research laboratory for the Navy and Marine Corps. NRL conducts a broad program of scientific research, technology and advanced development. ONR Headquarters is in the Ballston neighborhood of Arlington, Virginia. ONR Global has offices overseas in Santiago, Sao Paulo, London, Prague, Singapore, and Tokyo. Overview ONR was authorized by an Act of Congress, Public Law 588, and subsequently approved by President ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing military alliances: the Allies and the Axis powers. World War II was a total war that directly involved more than 100 million personnel from more than 30 countries. The major participants in the war threw their entire economic, industrial, and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. Aircraft played a major role in the conflict, enabling the strategic bombing of population centres and deploying the only two nuclear weapons ever used in war. World War II was by far the deadliest conflict in human history; it resulted in 70 to 85 million fatalities, mostly among civilians. Tens of millions died due to genocides (including the Holocaust), starvation, ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Egon Pearson
Egon Sharpe Pearson (11 August 1895 – 12 June 1980) was one of three children of Karl Pearson and Maria, née Sharpe, and, like his father, a leading British statistician. Career He was educated at Winchester College and Trinity College, Cambridge, and succeeded his father as professor of statistics at University College London and as editor of the journal ''Biometrika''. Pearson is best known for development of the Neyman–Pearson lemma of statistical hypothesis testing. He was elected a Fellow of the Econometric Society in 1948. He was President of the Royal Statistical Society in 1955–56, and was awarded its Guy Medal in gold in 1955. He was appointed a CBE in 1946. He was elected a Fellow of the Royal Society in March 1966. His candidacy citation read: Family life Pearson married Eileen Jolly in 1934 and the couple had two daughters, Judith and Sarah. Eileen died of pneumonia in 1949. Pearson subsequently married Margaret Theodosia Scott in 1967 and the couple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jerzy Neyman
Jerzy Neyman (April 16, 1894 – August 5, 1981; born Jerzy Spława-Neyman; ) was a Polish mathematician and statistician who spent the first part of his professional career at various institutions in Warsaw, Poland and then at University College London, and the second part at the University of California, Berkeley. Neyman first introduced the modern concept of a confidence interval into statistical hypothesis testing and co-revised Ronald Fisher's null hypothesis testing (in collaboration with Egon Pearson). Life and career He was born into a Polish family in Bendery, in the Bessarabia Governorate of the Russian Empire, the fourth of four children of Czesław Spława-Neyman and Kazimiera Lutosławska. His family was Roman Catholic and Neyman served as an altar boy during his early childhood. Later, Neyman would become an agnostic. Neyman's family descended from a long line of Polish nobles and military heroes. He graduated from the Kamieniec Podolski gubernial gymnasium for boys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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