Dispersion may refer to:
Economics and finance
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Dispersion (finance)
In statistics, dispersion (also called variability, scatter, or spread) is the extent to which a distribution is stretched or squeezed. Common examples of measures of statistical dispersion are the variance, standard deviation, and interquart ...
, a measure for the statistical distribution of portfolio returns
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Price dispersion
In economics, price dispersion is variation in prices across sellers of the same item, holding fixed the item's characteristics. Price dispersion can be viewed as a measure of trading frictions (or, tautologically, as a violation of the law of one ...
, a variation in prices across sellers of the same item
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Wage dispersion In economics, wage dispersion is the variation in wages encountered in an economy.
See also
*Search theory
* Price dispersion
*Economic inequality
There are wide varieties of economic inequality, most notably income inequality measured usin ...
, the amount of variation in wages encountered in an economy
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Dispersed knowledge
Dispersed knowledge in economics is the notion that no single agent has information as to all of the factors which influence prices and production throughout the system. The term has been both expanded upon and popularized by American economist Th ...
, notion that any one person is unable to perceive all economic forces
Science and mathematics
Mathematics
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Statistical dispersion
In statistics, dispersion (also called variability, scatter, or spread) is the extent to which a Probability distribution, distribution is stretched or squeezed. Common examples of measures of statistical dispersion are the variance, standard de ...
, a quantifiable variation of measurements of differing members of a population
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Index of dispersion
In probability theory and statistics, the index of dispersion, dispersion index, coefficient of dispersion, relative variance, or variance-to-mean ratio (VMR), like the coefficient of variation, is a normalized measure of the dispersion of a p ...
, a normalized measure of the dispersion of a probability distribution
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Dispersion point In topology, a dispersion point or explosion point is a point in a topological space the removal of which leaves the space highly disconnected.
More specifically, if ''X'' is a connected topological space containing the point ''p'' and at least t ...
, a point in a topological space the removal of which leaves the space highly disconnected
Physics
*The dependence of wave velocity on frequency or wavelength:
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Dispersion (optics)
In optics, and by analogy other branches of physics dealing with wave propagation, dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency; sometimes the term chromatic dispersion is used for specificity to o ...
, for light waves
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Dispersion (water waves)
In fluid dynamics, dispersion of water waves generally refers to frequency dispersion, which means that waves of different wavelengths travel at different phase speeds. Water waves, in this context, are waves propagating on the water surface, ...
, for water waves
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Acoustic dispersion Acoustic dispersion is the phenomenon of a sound wave separating into its component frequencies as it passes through a material. The phase velocity of the sound wave is viewed as a function of frequency. Hence, separation of component frequencies ...
, for sound waves
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Dispersion relation
In the physical sciences and electrical engineering, dispersion relations describe the effect of dispersion on the properties of waves in a medium. A dispersion relation relates the wavelength or wavenumber of a wave to its frequency. Given t ...
, the mathematical description of dispersion in a system
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Modal dispersion
Modal dispersion is a distortion mechanism occurring in multimode fibers and other waveguides, in which the signal is spread in time because the propagation velocity of the optical signal is not the same for all modes. Other names for this phenom ...
, spreading of signals in multimode fibers and waveguides by a distortion mechanism
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Polarization mode dispersion
Polarization mode dispersion (PMD) is a form of modal dispersion where two different polarizations of light in a waveguide, which normally travel at the same speed, travel at different speeds due to random imperfections and asymmetries, causing ...
, a form of modal dispersion
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Dielectric dispersion, the dependence of the permittivity of a dielectric material on the frequency of an applied electric field
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Dispersive mass transfer
Dispersive mass transfer, in fluid dynamics, is the spreading of mass from highly concentrated areas to less concentrated areas. It is one form of mass transfer.
Dispersive mass flux is analogous to diffusion, and it can also be described using F ...
, in fluid dynamics, the spreading of mass from areas of high to low concentration
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Atmospheric dispersion modeling
Atmospheric dispersion modeling is the mathematical simulation of how air pollutants disperse in the ambient atmosphere. It is performed with computer programs that include algorithms to solve the mathematical equations that govern the pollutant ...
, mathematical simulation of how air pollutants disperse in the ambient atmosphere
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London dispersion force
London dispersion forces (LDF, also known as dispersion forces, London forces, instantaneous dipole–induced dipole forces, fluctuating induced dipole bonds or loosely as van der Waals forces) are a type of intermolecular force acting between a ...
, an instantaneous induced dipole-induced dipole
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Dispersed particle resistance, a measured parameter to characterize battery active materials
Other sciences
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Biological dispersal, the distribution of animals, spores, fruits and their seeds, etc.
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Dispersion (chemistry)
A dispersion is a system in which distributed particles of one material are dispersed in a continuous phase of another material. The two phases may be in the same or different states of matter.
Dispersions are classified in a number of diffe ...
, a system in which particles are dispersed in a continuous phase of a different composition
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Dispersion (geology)
Dispersion is a process that occurs in soils that are particularly vulnerable to erosion by water. In soil layers where clays are saturated with sodium ions ("sodic soils"), soil can break down very easily into fine particles and wash away. This ca ...
, a process whereby sodic soil disperses when exposed to water
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Dispersion (materials science) In materials science, dispersion is the fraction of atoms of a material exposed to the surface. In general:
:''D'' = ''N''S/''N''T
where ''D'' is the dispersion, ''N''S is the number of surface atoms and ''N''T is the total number of atoms of th ...
, the fraction of atoms of a material exposed to the surface
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Dispersion polymerization
In polymer science, dispersion polymerization is a heterogeneous polymerization process carried out in the presence of a polymeric stabilizer in the reaction medium. Dispersion polymerization is a type of precipitation polymerization, meaning the ...
, a polymerization process
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Velocity dispersion
In astronomy, the velocity dispersion (''σ'') is the statistical dispersion of velocities about the mean velocity for a group of astronomical objects, such as an open cluster, globular cluster, galaxy, galaxy cluster, or supercluster. By measurin ...
, the statistical variation of velocities about the mean velocity for a group of astronomical objects
Other uses
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Hellenistic Judaism#Hellenism, Jewish communities who lived amongst the gentiles in the first century CE
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''Dispersion'' (album), the second album by High Rise
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Dispersion Technology
Dispersion Technology Inc is a scientific instrument manufacturer located in Bedford Hills, New York. It was founded in 1996 by Philip Goetz (former Chairman, retired in 2010) and Dr. Andrei Dukhin (current CEO). The company develops and sells ...
, a scientific instrument manufacturer located in Bedford Hills, New York
See also
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Dispersal (disambiguation)
Dispersal may refer to:
* Biological dispersal, the movement of organisms from their birth site to their breeding site, or from one breeding site to another
** Dispersal vector, forces that carry seeds for plants
** Oceanic dispersal, the moveme ...
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Dispersive (disambiguation)
Dispersive may refer to:
*Dispersive partial differential equation, a partial differential equation where waves of different wavelength propagate at different phase velocities
* Dispersive phase from Biological dispersal
* Dispersive medium, a med ...
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Dispersity
In chemistry, the dispersity is a measure of the heterogeneity of sizes of molecules or particles in a mixture. A collection of objects is called uniform if the objects have the same size, shape, or mass. A sample of objects that have an inconsi ...
, a measure of the heterogeneity of sizes of molecules or particles in a mixture
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