|
Structural Equation Modeling
Structural equation modeling (SEM) is a label for a diverse set of methods used by scientists in both experimental and observational research across the sciences, business, and other fields. It is used most in the social and behavioral sciences. A definition of SEM is difficult without reference to highly technical language, but a good starting place is the name itself. SEM involves the construction of a '' model'', to represent how various aspects of an observable or theoretical phenomenon are thought to be causally structurally related to one another. The '' structural'' aspect of the model implies theoretical associations between variables that represent the phenomenon under investigation. The postulated causal structuring is often depicted with arrows representing causal connections between variables (as in Figures 1 and 2) but these causal connections can be equivalently represented as equations. The causal structures imply that specific patterns of connections should ap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Example Structural Equation Model
Example may refer to: * '' exempli gratia'' (e.g.), usually read out in English as "for example" * .example, reserved as a domain name that may not be installed as a top-level domain of the Internet ** example.com, example.net, example.org, example.edu, second-level domain names reserved for use in documentation as examples * HMS ''Example'' (P165), an Archer-class patrol and training vessel of the Royal Navy Arts * ''The Example'', a 1634 play by James Shirley * ''The Example'' (comics), a 2009 graphic novel by Tom Taylor and Colin Wilson * Example (musician), the British dance musician Elliot John Gleave (born 1982) * ''Example'' (album), a 1995 album by American rock band For Squirrels See also * * Exemplar (other), a prototype or model which others can use to understand a topic better * Exemplum, medieval collections of short stories to be told in sermons * Eixample The Eixample (; ) is a district of Barcelona between the old city ( Ciutat Vella) an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Intelligence
Human intelligence is the intellectual capability of humans, which is marked by complex cognitive feats and high levels of motivation and self-awareness. High intelligence is associated with better outcomes in life. Through intelligence, humans possess the cognitive abilities to learn, form concepts, understand, apply logic and reason, including the capacities to recognize patterns, plan, innovate, solve problems, make decisions, retain information, and use language to communicate. There are conflicting ideas about how intelligence is measured, ranging from the idea that intelligence is fixed upon birth, or that it is malleable and can change depending on an individual's mindset and efforts. Several subcategories of intelligence, such as emotional intelligence or social intelligence, are heavily debated as to whether they are traditional forms of intelligence. They are generally thought to be distinct processes that occur, though there is speculation that they tie into tradit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Expectation–maximization Algorithm
In statistics, an expectation–maximization (EM) algorithm is an iterative method to find (local) maximum likelihood or maximum a posteriori (MAP) estimates of parameters in statistical models, where the model depends on unobserved latent variables. The EM iteration alternates between performing an expectation (E) step, which creates a function for the expectation of the log-likelihood evaluated using the current estimate for the parameters, and a maximization (M) step, which computes parameters maximizing the expected log-likelihood found on the ''E'' step. These parameter-estimates are then used to determine the distribution of the latent variables in the next E step. History The EM algorithm was explained and given its name in a classic 1977 paper by Arthur Dempster, Nan Laird, and Donald Rubin. They pointed out that the method had been "proposed many times in special circumstances" by earlier authors. One of the earliest is the gene-counting method for estimating allele ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Covariance Matrix
In probability theory and statistics, a covariance matrix (also known as auto-covariance matrix, dispersion matrix, variance matrix, or variance–covariance matrix) is a square matrix giving the covariance between each pair of elements of a given random vector. Any covariance matrix is symmetric and positive semi-definite and its main diagonal contains variances (i.e., the covariance of each element with itself). Intuitively, the covariance matrix generalizes the notion of variance to multiple dimensions. As an example, the variation in a collection of random points in two-dimensional space cannot be characterized fully by a single number, nor would the variances in the x and y directions contain all of the necessary information; a 2 \times 2 matrix would be necessary to fully characterize the two-dimensional variation. The covariance matrix of a random vector \mathbf is typically denoted by \operatorname_ or \Sigma. Definition Throughout this article, boldfaced unsub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Point
In statistics, a unit of observation is the unit described by the data that one analyzes. A study may treat groups as a unit of observation with a country as the unit of analysis, drawing conclusions on group characteristics from data collected at the national level. For example, in a study of the demand for money, the unit of observation might be chosen as the individual, with different observations (data points) for a given point in time differing as to which individual they refer to; or the unit of observation might be the country, with different observations differing only in regard to the country they refer to. Unit of observation vs unit of analysis The unit of observation should not be confused with the unit of analysis. A study may have a differing unit of observation and unit of analysis: for example, in community research, the research design may collect data at the individual level of observation but the level of analysis might be at the neighborhood level, drawing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Recursive Definition
In mathematics and computer science, a recursive definition, or inductive definition, is used to define the elements in a set in terms of other elements in the set ( Aczel 1977:740ff). Some examples of recursively-definable objects include factorials, natural numbers, Fibonacci numbers, and the Cantor ternary set. A recursive definition of a function defines values of the function for some inputs in terms of the values of the same function for other (usually smaller) inputs. For example, the factorial function ''n''! is defined by the rules :0! = 1. :(''n'' + 1)! = (''n'' + 1)·''n''!. This definition is valid for each natural number ''n'', because the recursion eventually reaches the base case of 0. The definition may also be thought of as giving a procedure for computing the value of the function ''n''!, starting from ''n'' = 0 and proceeding onwards with ''n'' = 1, ''n'' = 2, ''n'' = 3 etc. The recursion theorem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alex Liu
The Independent Federation of Chinese Students and Scholars (IFCSS) was founded on August 1, 1989, when over 1000 Chinese student representatives from more than 200 Chinese Students and Scholars Association in major U.S. universities held their First Congress of Chinese Students and Scholars in the United States at the University of Illinois at Chicago. The mission of IFCSS was to promote democracy in China and to protect the interests of the Chinese students and scholars studying in the United States, as a response to Tiananmen Square protests of 1989. Since its birth, IFCSS had become one of the most influential overseas Chinese students groups in history. It had lobbied successfully in U.S. Congress for many bills including the Chinese Student Protection Act of 1992, organized the well-known "Washington March for Chinese Democracy" in 1989, and united tens of thousands of Chinese students together for many years since 1989. However, its relevance and importance have been decl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Denis Sargan
John Denis Sargan, FBA (23 August 1924 – 13 April 1996) was a British econometrician who specialized in the analysis of economic time-series. Sargan was born in Doncaster, Yorkshire in 1924, and was educated at Doncaster Grammar School and St John's College, Cambridge. He made many contributions, notably in instrumental variables estimation, Edgeworth expansions for the distributions of econometric estimators, identification conditions in simultaneous equations models, asymptotic tests for overidentifying restrictions in homoskedastic equations and exact tests for unit roots in autoregressive and moving average models. At the LSE, Sargan was Professor of Econometrics from 1964–1984.https://www.independent.co.uk/news/people/obituary--professor-denis-sargan-1305657.html Obituary: Professor Denis Sargan Friday, 19 April 1996 Sargan was President of the Econometric Society, a Fellow of the British Academy and an (honorary foreign) member of the American Academy of Arts ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert Basmann
Robert Leon Basmann (born January 15, 1926) is an American econometrician. He was a Professor of Econometrics at Texas A&M University until his retirement. He served as a lecturer at Binghamton University after his retirement. As of at least as recently as 2019 Basmann was still listed on Binghamton Universities listing of emeritus professors. Basmann held academic appointments at Northwestern University, University of Chicago and Purdue University prior to joining the faculty at Texas A&M. Basmann earned a Ph.D. in economics from Iowa State University Iowa State University of Science and Technology (Iowa State University, Iowa State, or ISU) is a public land-grant research university in Ames, Iowa. Founded in 1858 as the Iowa Agricultural College and Model Farm, Iowa State became one of the ... in 1955. He is credited, along with Henri Theil, for deriving two stage least squares estimation. References External links Website at Binghamton University 1926 birth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henri Theil
Henri (Hans) Theil (October 13, 1924 – August 20, 2000) was a Dutch econometrician and professor at the Netherlands School of Economics in Rotterdam, known for his contributions to the field of econometrics. Biography Born in Amsterdam, Theil started to study mathematics and physics at Utrecht University in 1942. Later in World War II he was arrested and was imprisoned in Vught. After the war he started to study economics at the Gemeente-Universiteit Amsterdam, where in 1951 he received his PhD under Pieter Hennipman.Raj, Baldev. "Henri Theil’s Biography and his Contributions to Economics and Econometrics: An Overview." Henri Theil’s Contributions to Economics and Econometrics. Springer Netherlands, 1992. 3–16. After graduation Theil started working as researcher for the Bureau for Economic Policy Analysis under Jan Tinbergen. In 1953 he was appointed Professor of Econometrics at the Netherlands School of Economics as successor of Jan Tinbergen. Here he founded the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LISREL
LISREL (linear structural relations) is a proprietary statistical software package used in structural equation modeling (SEM) for manifest and latent variables. It requires a "fairly high level of statistical sophistication". History LISREL was developed in the 1970s by Karl Jöreskog, then a scientist at Educational Testing Service in Princeton, New Jersey, and Dag Sörbom, later both professors of Uppsala University in Sweden. The most current version is LISREL 11 and can be downloaded from https://ssicentral.com/index.php/products/lisrel/. Command language, graphical user interface and delivery LISREL is mainly syntax-based, although recent versions have featured a graphical user interface (GUI). SSI (Scientific Software International) has recently changed from e-Academy to a "home-built" solution for distributing the rental (6- or 12-month) versions of their software. See also * Confirmatory factor analysis * Multivariate analysis * Path analysis (statistics) * Structural ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karl Gustav Jöreskog
Karl Gustav Jöreskog (born 25 April 1935) is a Swedish statistician. Jöreskog is a Professor Emeritus at Uppsala University, and a co-author (with Dag Sörbom) of the LISREL statistical program. He is also a member of the Royal Swedish Academy of Sciences. Jöreskog received his bachelor's, master's, and doctoral degrees in Uppsala University. He is also a former student of Herman Wold. He was a statistician at Educational Testing Service (ETS) and a visiting professor at Princeton University. Research Jöreskog proposed a reliable numerical method for computing maximum-likelihood estimates in factor analysis; similarly reliable methods were also proposed by Gerhard Derflinger, Robert Jennrich, and Stephen M. Robinson at roughly the same time. Jöreskog's Fortran codes helped to popularize factor analysis around the world. While working at the Educational Testing Service and giving lectures at Princeton University, Jöreskog proposed a linear model for the analysis of covar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
