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Urban Scaling
Urban scaling is an area of research within the study of cities as complex systems. It examines how various urban indicators change systematically with city size. The literature on urban scaling was motivated by the success of scaling theory in biology, itself motivated in turn by the success of scaling in physics. Crucial insights from scaling analysis applied to a system can emerge from finding power-law function relationships between variables of interest and the size of the system (as opposed to finding power-law probability distributions). Power-laws have an implicit self-similarity which suggests universal mechanisms at work, which in turn support the search for fundamental laws. The study of power-laws is closely linked to the study of critical phenomena in physics, in which emergent properties and scale invariance are central and organizing concepts. These concepts resurface in the study of complex systems, and are of particular importance in the urban scaling framework. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Complex System
A complex system is a system composed of many components that may interact with one another. Examples of complex systems are Earth's global climate, organisms, the human brain, infrastructure such as power grid, transportation or communication systems, complex software and electronic systems, social and economic organizations (like cities), an ecosystem, a living Cell (biology), cell, and, ultimately, for some authors, the entire universe. The behavior of a complex system is intrinsically difficult to model due to the dependencies, competitions, relationships, and other types of interactions between their parts or between a given system and its environment. Systems that are "Complexity, complex" have distinct properties that arise from these relationships, such as Nonlinear system, nonlinearity, emergence, spontaneous order, Complex adaptive system, adaptation, and Feedback, feedback loops, among others. Because such systems appear in a wide variety of fields, the commonalities am ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Santa Fe Institute
The Santa Fe Institute (SFI) is an independent, nonprofit theoretical research institute located in Santa Fe, New Mexico, United States and dedicated to the multidisciplinary study of the fundamental principles of complex adaptive systems, including physical, computational, biological, and social systems. The institute is ranked 24th among the world's "Top Science and Technology Think Tanks" and 24th among the world's "Best Transdisciplinary Research Think Tanks" according to the 2020 edition of the ''Global Go To Think Tank Index Reports'', published annually by the University of Pennsylvania. The institute consists of a small number of resident faculty and postdoctoral researchers, a large group of external faculty whose primary appointments are at other institutions, and a number of visiting scholars. The institute is advised by a group of eminent scholars, including several Nobel Prize-winning scientists. Although theoretical scientific research is the institute's primary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urban Economics
Urban economics is broadly the economic study of urban areas; as such, it involves using the tools of economics to analyze urban issues such as crime, education, public transit, housing, and local government finance. More specifically, it is a branch of microeconomics that studies the urban spatial structure and the location of households and firms . Historically, much like economics generally, urban economics was influenced by multiple schools of thought, including original institutional economics and Marxist economics. These heterodox economic currents continue to be used in contemporary political-economic analyses of cities. But, most urban economics today is neoclassical in orientation and centred largely around urban experiences in the Global North. This dominant urban economics also influences mainstream media like ''The Economist.'' Today, much urban economic analysis relies on a particular model of urban spatial structure, the monocentric city model pioneered in the 1960s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Law Of Large Numbers
In probability theory, the law of large numbers is a mathematical law that states that the average of the results obtained from a large number of independent random samples converges to the true value, if it exists. More formally, the law of large numbers states that given a sample of independent and identically distributed values, the sample mean converges to the true mean. The law of large numbers is important because it guarantees stable long-term results for the averages of some random events. For example, while a casino may lose money in a single spin of the roulette wheel, its earnings will tend towards a predictable percentage over a large number of spins. Any winning streak by a player will eventually be overcome by the parameters of the game. Importantly, the law applies (as the name indicates) only when a ''large number'' of observations are considered. There is no principle that a small number of observations will coincide with the expected value or that a stre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extreme Value Theory
Extreme value theory or extreme value analysis (EVA) is the study of extremes in statistical distributions. It is widely used in many disciplines, such as structural engineering, finance, economics, earth sciences, traffic prediction, and Engineering geology, geological engineering. For example, EVA might be used in the field of hydrology to estimate the probability of an unusually large flooding event, such as the 100-year flood. Similarly, for the design of a breakwater (structure), breakwater, a coastal engineer would seek to estimate the 50 year wave and design the structure accordingly. Data analysis Two main approaches exist for practical extreme value analysis. The first method relies on deriving block maxima (minima) series as a preliminary step. In many situations it is customary and convenient to extract the annual maxima (minima), generating an ''annual maxima series'' (AMS). The second method relies on extracting, from a continuous record, the peak values reac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Normal Distribution
In probability theory and statistics, a normal distribution or Gaussian distribution is a type of continuous probability distribution for a real-valued random variable. The general form of its probability density function is f(x) = \frac e^\,. The parameter is the mean or expectation of the distribution (and also its median and mode), while the parameter \sigma^2 is the variance. The standard deviation of the distribution is (sigma). A random variable with a Gaussian distribution is said to be normally distributed, and is called a normal deviate. Normal distributions are important in statistics and are often used in the natural and social sciences to represent real-valued random variables whose distributions are not known. Their importance is partly due to the central limit theorem. It states that, under some conditions, the average of many samples (observations) of a random variable with finite mean and variance is itself a random variable—whose distribution c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heavy-tailed Distribution
In probability theory, heavy-tailed distributions are probability distributions whose tails are not exponentially bounded: that is, they have heavier tails than the exponential distribution. Roughly speaking, “heavy-tailed” means the distribution decreases more slowly than an exponential distribution, so extreme values are more likely. In many applications it is the right tail of the distribution that is of interest, but a distribution may have a heavy left tail, or both tails may be heavy. There are three important subclasses of heavy-tailed distributions: the fat-tailed distributions, the long-tailed distributions, and the subexponential distributions. In practice, all commonly used heavy-tailed distributions belong to the subexponential class, introduced by Jozef Teugels. There is still some discrepancy over the use of the term heavy-tailed. There are two other definitions in use. Some authors use the term to refer to those distributions which do not have all their p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Complex System
A complex system is a system composed of many components that may interact with one another. Examples of complex systems are Earth's global climate, organisms, the human brain, infrastructure such as power grid, transportation or communication systems, complex software and electronic systems, social and economic organizations (like cities), an ecosystem, a living Cell (biology), cell, and, ultimately, for some authors, the entire universe. The behavior of a complex system is intrinsically difficult to model due to the dependencies, competitions, relationships, and other types of interactions between their parts or between a given system and its environment. Systems that are "Complexity, complex" have distinct properties that arise from these relationships, such as Nonlinear system, nonlinearity, emergence, spontaneous order, Complex adaptive system, adaptation, and Feedback, feedback loops, among others. Because such systems appear in a wide variety of fields, the commonalities am ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Power Law
In statistics, a power law is a Function (mathematics), functional relationship between two quantities, where a Relative change and difference, relative change in one quantity results in a relative change in the other quantity proportional to the change raised to a constant exponent: one quantity varies as a power of another. The change is independent of the initial size of those quantities. For instance, the area of a square has a power law relationship with the length of its side, since if the length is doubled, the area is multiplied by 2, while if the length is tripled, the area is multiplied by 3, and so on. Empirical examples The distributions of a wide variety of physical, biological, and human-made phenomena approximately follow a power law over a wide range of magnitudes: these include the sizes of craters on the moon and of solar flares, cloud sizes, the foraging pattern of various species, the sizes of activity patterns of neuronal populations, the frequencies of words ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Claude S
Claude may refer to: People and fictional characters * Claude (given name), a list of people and fictional characters * Claude (surname), a list of people * Claude Callegari (1962–2021), English Arsenal supporter * Claude Debussy (1862–1918), French composer * Claude Kiambe (born 2003), Congolese-born Dutch singer * Claude Lévi-Strauss (1908–2009), French anthropologist and ethnologist * Claude Lorrain (c. 1600–1682), French landscape painter, draughtsman and etcher traditionally called just "Claude" in English * Claude Makélélé (born 1973), French football manager * Claude McKay (1890–1948), Jamaican-American writer and poet * Claude Monet (1840–1926), French painter * Claude Rains (1889–1967), British-American actor * Claude Shannon (1916–2001), American mathematician, electrical engineer and computer scientist * Madame Claude (1923–2015), French brothel keeper Fernande Grudet Places * Claude, Texas, a city * Claude, West Virginia, an unincorporated communi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Louis Wirth
Louis Wirth (August 28, 1897 – May 3, 1952) was an American sociologist and member of the Chicago school of sociology. His interests included city life, minority group behavior, and mass media, and he is recognised as one of the leading urban sociologists. He spent most of his academic career at the University of Chicago. He was the first president of the International Sociological Association (1949–1952) and the 37th president of the American Sociological Association (1947). Early life Louis Wirth was born in the small village of Gemünden in the Hunsrück, Germany. He was one of seven children born to Rosalie Lorig (1868–1948, from Butzweiler/ Eifel) and Joseph Wirth. Gemünden was a pastoral community, and Joseph Wirth earned a living as a cattle dealer. The family was Jewish and both of his parents were religiously active. Wirth migrated in 1911 at the age of 14 to the United States where he lived with his older sister at his uncle's home in Omaha, Nebraska in 1911. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Émile Durkheim
David Émile Durkheim (; or ; 15 April 1858 – 15 November 1917) was a French Sociology, sociologist. Durkheim formally established the academic discipline of sociology and is commonly cited as one of the principal architects of modern social science, along with both Karl Marx and Max Weber. Much of Durkheim's work was concerned with how societies can maintain their social integration, integrity and coherence in modernity, an era in which traditional social and religious ties are much less universal, and in which new social institutions have come into being. Durkheim's conception of the scientific study of society laid the groundwork for modern sociology, and he used such scientific tools as statistics, Survey (human research), surveys, and historical observation in his analysis of suicides in Roman Catholic and Protestant groups. Durkheim's first major sociological work was (1893; ''The Division of Labour in Society''), followed in 1895 by (''The Rules of Sociological Me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
