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The Statistical Research Group Of World War II
The Statistical Research Group (SRG) was a research group at Columbia University focused on military problems during World War II. Abraham Wald, Allen Wallis, Herbert Solomon, Frederick Mosteller, George Stigler and Milton Friedman were all part of the group in which 18 researchers participated. Wallis, Stigler and Friedman met as graduate students at the University of Chicago. Despite their shared alma mater there is no evidence that Stigler and Friedman had grown close before serving on the SRG staff together in New York City. The SRG was disbanded at the end of World War II. Background Statistical analysis was widely used by Federal agencies after the New Deal. The statistical publications of the United States became more sophisticated between 1930 and 1940. During the mobilization to war (1940-1941) and continuing on during the war, statistics continued to gain in importance with applications in operations research and management information systems (MIS). The Statistical C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Columbia University
Columbia University (also known as Columbia, and officially as Columbia University in the City of New York) is a private research university in New York City. Established in 1754 as King's College on the grounds of Trinity Church in Manhattan, Columbia is the oldest institution of higher education in New York and the fifth-oldest institution of higher learning in the United States. It is one of nine colonial colleges founded prior to the Declaration of Independence. It is a member of the Ivy League. Columbia is ranked among the top universities in the world. Columbia was established by royal charter under George II of Great Britain. It was renamed Columbia College in 1784 following the American Revolution, and in 1787 was placed under a private board of trustees headed by former students Alexander Hamilton and John Jay. In 1896, the campus was moved to its current location in Morningside Heights and renamed Columbia University. Columbia scientists and scholars have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operations Research
Operations research ( en-GB, operational research) (U.S. Air Force Specialty Code: Operations Analysis), often shortened to the initialism OR, is a discipline that deals with the development and application of analytical methods to improve decision-making. It is considered to be a subfield of mathematical sciences. The term management science is occasionally used as a synonym. Employing techniques from other mathematical sciences, such as modeling, statistics, and optimization, operations research arrives at optimal or near-optimal solutions to decision-making problems. Because of its emphasis on practical applications, operations research has overlap with many other disciplines, notably industrial engineering. Operations research is often concerned with determining the extreme values of some real-world objective: the maximum (of profit, performance, or yield) or minimum (of loss, risk, or cost). Originating in military efforts before World War II, its techniques have grown to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Statistical Organizations
Statistics (from German: ''Statistik'', "description of a state, a country") is the discipline that concerns the collection, organization, analysis, interpretation, and presentation of data. In applying statistics to a scientific, industrial, or social problem, it is conventional to begin with a statistical population or a statistical model to be studied. Populations can be diverse groups of people or objects such as "all people living in a country" or "every atom composing a crystal". Statistics deals with every aspect of data, including the planning of data collection in terms of the design of surveys and experiments.Dodge, Y. (2006) ''The Oxford Dictionary of Statistical Terms'', Oxford University Press. When census data cannot be collected, statisticians collect data by developing specific experiment designs and survey samples. Representative sampling assures that inferences and conclusions can reasonably extend from the sample to the population as a whole. An expe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regression Model
In statistical modeling, regression analysis is a set of statistical processes for estimating the relationships between a dependent variable (often called the 'outcome' or 'response' variable, or a 'label' in machine learning parlance) and one or more independent variables (often called 'predictors', 'covariates', 'explanatory variables' or 'features'). The most common form of regression analysis is linear regression, in which one finds the line (or a more complex linear combination) that most closely fits the data according to a specific mathematical criterion. For example, the method of ordinary least squares computes the unique line (or hyperplane) that minimizes the sum of squared differences between the true data and that line (or hyperplane). For specific mathematical reasons (see linear regression), this allows the researcher to estimate the conditional expectation (or population average value) of the dependent variable when the independent variables take on a given set of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aircraft Engines
An aircraft engine, often referred to as an aero engine, is the power component of an aircraft propulsion system. Most aircraft engines are either piston engines or gas turbines, although a few have been rocket powered and in recent years many small UAVs have used electric motors. Manufacturing industry In commercial aviation the major Western manufacturers of turbofan engines are Pratt & Whitney (a subsidiary of Raytheon Technologies), General Electric, Rolls-Royce, and CFM International (a joint venture of Safran Aircraft Engines and General Electric). Russian manufacturers include the United Engine Corporation, Aviadvigatel and Klimov. Aeroengine Corporation of China was formed in 2016 with the merger of several smaller companies. The largest manufacturer of turboprop engines for general aviation is Pratt & Whitney. General Electric announced in 2015 entrance into the market. Development history * 1848: John Stringfellow made a steam engine for a 10-foot wingspan model ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alloys
An alloy is a mixture of chemical elements of which at least one is a metal. Unlike chemical compounds with metallic bases, an alloy will retain all the properties of a metal in the resulting material, such as electrical conductivity, ductility, opacity, and luster, but may have properties that differ from those of the pure metals, such as increased strength or hardness. In some cases, an alloy may reduce the overall cost of the material while preserving important properties. In other cases, the mixture imparts synergistic properties to the constituent metal elements such as corrosion resistance or mechanical strength. Alloys are defined by a metallic bonding character. The alloy constituents are usually measured by mass percentage for practical applications, and in atomic fraction for basic science studies. Alloys are usually classified as substitutional or interstitial alloys, depending on the atomic arrangement that forms the alloy. They can be further classified as homogene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Office Of Scientific Research And Development
The Office of Scientific Research and Development (OSRD) was an agency of the United States federal government created to coordinate scientific research for military purposes during World War II. Arrangements were made for its creation during May 1941, and it was created formally by Executive Order 8807 on June 28, 1941. It superseded the work of the National Defense Research Committee (NDRC), was given almost unlimited access to funding and resources, and was directed by Vannevar Bush, who reported only to President Franklin Delano Roosevelt. The research was widely varied, and included projects devoted to new and more accurate bombs, reliable detonators, work on the proximity fuze, guided missiles, radar and early-warning systems, lighter and more accurate hand weapons, more effective medical treatments (including work to make penicillin at scale, which was necessary for its use as a drug), more versatile vehicles, and, the most secret of all, the S-1 Section, which later be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Defense Research Committee
The National Defense Research Committee (NDRC) was an organization created "to coordinate, supervise, and conduct scientific research on the problems underlying the development, production, and use of mechanisms and devices of warfare" in the United States from June 27, 1940, until June 28, 1941. Most of its work was done with the strictest secrecy, and it began research of what would become some of the most important technology during World War II, including radar and the atomic bomb. It was superseded by the Office of Scientific Research and Development in 1941, and reduced to merely an advisory organization until it was eventually terminated during 1947. Organization The NDRC was created by an order of President Franklin Delano Roosevelt on June 27, 1940. It was part of the Council of National Defense, which had been created during 1916 to coordinate industry and resources for national security purposes. Vannevar Bush, the director of the Carnegie Institution, had pressed for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Applied Mathematics Panel
The Applied Mathematics Panel (AMP) was created at the end of 1942 as a division of the National Defense Research Committee (NDRC) within the Office of Scientific Research and Development (OSRD) in order to solve mathematical problems related to the military effort in World War II, particularly those of the other NDRC divisions. The panel's headquarters were in Manhattan, and it was directed by Warren Weaver, formerly of NDRC Division 7, Fire Control. It contracted projects out to various research groups, notably at Princeton and Columbia Universities. In addition to work immediately relevant to the war effort, mathematicians involved with the panel also pursued problems of interest to them without contracts from outside organizations. Most notably, Abraham Wald developed the statistical technique of sequential analysis In statistics, sequential analysis or sequential hypothesis testing is statistical analysis where the sample size is not fixed in advance. Instead data are eva ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Air Force
The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Signal Corps, the USAF was established as a separate branch of the United States Armed Forces in 1947 with the enactment of the National Security Act of 1947. It is the second youngest branch of the United States Armed Forces and the fourth in order of precedence. The United States Air Force articulates its core missions as air supremacy, global integrated intelligence, surveillance and reconnaissance, rapid global mobility, global strike, and command and control. The United States Air Force is a military service branch organized within the Department of the Air Force, one of the three military departments of the Department of Defense. The Air Force through the Department of the Air Force is headed by the civilian Secretary of the Air Force ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Management Information Systems
A management information system (MIS) is an information system used for decision-making, and for the coordination, control, analysis, and visualization of information in an organization. The study of the management information systems involves people, processes and technology in an organizational context. In a corporate setting, the ultimate goal of using management information system is to increase the value and profits of the business. History While it can be contested that the history of management information system dates as far back as companies using ledgers to keep track of accounting, the modern history of MIS can be divided into five ''eras'' originally identified by Kenneth C. Laudon and Jane Laudon in their seminal textbook ''Management Information Systems.'' * First Era – Mainframe and minicomputer computing * Second Era – Personal computers * Third Era – Client/server networks * Fourth Era – Enterprise computing * Fifth Era – Cloud computing The ''fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Office Of War Mobilization
The Office of War Mobilization (OWM) was an independent agency of the United States government formed during World War II to coordinate all government agencies involved in the war effort. It was formed on May 27, 1943 by Executive Order 9347. It was headed by James F. Byrnes, a former U.S. Senator and Supreme Court Justice. Byrnes had previously been head of the Office of Economic Stabilization, which controlled prices and taxes. The OWM supervised the OES, and also the War Production Board and other agencies. It was re-titled the Office of War Mobilization and Reconversion on October 3, 1944. Byrnes' authority as head of the OWM was so far-reaching, he was dubbed the "assistant President". See also *Office of War Information References External linksMobilization in World War IIbrochure at the US Army Center of Military History The United States Army Center of Military History (CMH) is a directorate within the United States Army Training and Doctrine Command. The Insti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
