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Tightness (other)
Tightness may refer to: In mathematics, * Tightness of (a collection of) measures is a concept in measure (and probability) theory * Tightness (topology) is also a cardinal function used in general topology In economics, * Tightness refers to the degree to which the number of unemployed workers exceed the number of posted job vacancies (or vice versa). * Market tightness, a point in time where it is very difficult to invest, but it is far easier to sell or to remove investments in return of monetary rewards In other fields, * Tightness of a rope indicates the rope is under tension * Tightness of a sealing means it is impermeable, that it seals well * Tightness is the art of being 'tight' (i.e., stingy or miserly) * Tightness can refer to something being cool See also * Tight (other) Tight may refer to: Clothing * Skin-tight garment, a garment that is held to the skin by elastic tension * Tights, a type of leg coverings fabric extending from the waist to fee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mathematics
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics with the major subdisciplines of number theory, algebra, geometry, and analysis, respectively. There is no general consensus among mathematicians about a common definition for their academic discipline. Most mathematical activity involves the discovery of properties of abstract objects and the use of pure reason to prove them. These objects consist of either abstractions from nature orin modern mathematicsentities that are stipulated to have certain properties, called axioms. A ''proof'' consists of a succession of applications of deductive rules to already established results. These results include previously proved theorems, axioms, andin case of abstraction from naturesome basic properties that are considered true starting poin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tightness Of Measures
In mathematics, tightness is a concept in measure theory. The intuitive idea is that a given collection of measures does not "escape to infinity". Definitions Let (X, T) be a Hausdorff space, and let \Sigma be a σ-algebra on X that contains the topology T. (Thus, every open subset of X is a measurable set and \Sigma is at least as fine as the Borel σ-algebra on X.) Let M be a collection of (possibly signed or complex) measures defined on \Sigma. The collection M is called tight (or sometimes uniformly tight) if, for any \varepsilon > 0, there is a compact subset K_ of X such that, for all measures \mu \in M, :, \mu, (X \setminus K_) 1 - \varepsilon. \, If a tight collection M consists of a single measure \mu, then (depending upon the author) \mu may either be said to be a tight measure or to be an inner regular measure. If Y is an X-valued random variable whose probability distribution on X is a tight measure then Y is said to be a separable random variable ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tightness (topology)
In mathematics, a cardinal function (or cardinal invariant) is a function that returns cardinal numbers. Cardinal functions in set theory * The most frequently used cardinal function is a function that assigns to a set ''A'' its cardinality, denoted by , ''A'' , . * Aleph numbers and beth numbers can both be seen as cardinal functions defined on ordinal numbers. * Cardinal arithmetic operations are examples of functions from cardinal numbers (or pairs of them) to cardinal numbers. * Cardinal characteristics of a (proper) ideal ''I'' of subsets of ''X'' are: :(I)=\min\. ::The "additivity" of ''I'' is the smallest number of sets from ''I'' whose union is not in ''I'' any more. As any ideal is closed under finite unions, this number is always at least \aleph_0; if ''I'' is a σ-ideal, then \operatorname(I) \ge \aleph_1. :\operatorname(I)=\min\. :: The "covering number" of ''I'' is the smallest number of sets from ''I'' whose union is all of ''X''. As ''X'' it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Economics
Economics () is the social science that studies the production, distribution, and consumption of goods and services. Economics focuses on the behaviour and interactions of economic agents and how economies work. Microeconomics analyzes what's viewed as basic elements in the economy, including individual agents and markets, their interactions, and the outcomes of interactions. Individual agents may include, for example, households, firms, buyers, and sellers. Macroeconomics analyzes the economy as a system where production, consumption, saving, and investment interact, and factors affecting it: employment of the resources of labour, capital, and land, currency inflation, economic growth, and public policies that have impact on these elements. Other broad distinctions within economics include those between positive economics, describing "what is", and normative economics, advocating "what ought to be"; between economic theory and applied economics; between ratio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Market Tightness
Market tightness is a measure of the liquidity of a market. High market tightness indicates relatively low liquidity and high transaction costs, whereas low market tightness indicates high liquidity and low transaction costs. For example, during the dotcom bubble, information technology companies were very difficult and expensive to buy a part of, through stock, loan, or other methods, due to the tightness of competition in the market. Equity markets In equity markets, market tightness is measured using percentage relative spread. Housing markets In housing markets, measures of market tightness include the probability of achieving a sale and house price appreciation. Tighter housing markets result in greater seller bargaining power and higher sale prices. Labour markets Labour market tightness is measured as the ratio of job vacancies per unemployed Unemployment, according to the OECD (Organisation for Economic Co-operation and Development), is people above a specified ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tension (physics)
In physics, tension is described as the pulling force transmitted axially by the means of a string, a rope, chain, or similar object, or by each end of a rod, truss member, or similar three-dimensional object; tension might also be described as the action-reaction pair of forces acting at each end of said elements. Tension could be the opposite of compression. At the atomic level, when atoms or molecules are pulled apart from each other and gain potential energy with a restoring force still existing, the restoring force might create what is also called tension. Each end of a string or rod under such tension could pull on the object it is attached to, in order to restore the string/rod to its relaxed length. Tension (as a transmitted force, as an action-reaction pair of forces, or as a restoring force) is measured in newtons in the International System of Units (or pounds-force in Imperial units). The ends of a string or other object transmitting tension will exert forces on the o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permeation
In physics and engineering, permeation (also called imbuing) is the penetration of a permeate (a fluid such as a liquid, gas, or vapor) through a solid. It is directly related to the concentration gradient of the permeate, a material's intrinsic permeability, and the materials' mass diffusivity. Permeation is modeled by equations such as Fick's laws of diffusion, and can be measured using tools such as a minipermeameter. Description The process of permeation involves the diffusion of molecules, called the permeant, through a membrane or interface. Permeation works through diffusion; the permeant will move from high concentration to low concentration across the interface. A material can be semipermeable, with the presence of a semipermeable membrane. Only molecules or ions with certain properties will be able to diffuse across such a membrane. This is a very important mechanism in biology where fluids inside a blood vessel need to be regulated and controlled. Permeation can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miser
A miser is a person who is reluctant to spend, sometimes to the point of forgoing even basic comforts and some necessities, in order to hoard money or other possessions. Although the word is sometimes used loosely to characterise anyone who is mean with their money, if such behaviour is not accompanied by taking delight in what is saved, it is not properly miserly. Misers as a type have been a perennial object of popular fascination and a fruitful source for writers and artists in many cultures. Accounting for misers One attempt to account for miserly behaviour was Sigmund Freud's theory of anal retentiveness, attributing the development of miserly behaviour to toilet training in childhood, although this explanation is not accepted by modern evidence-based psychology. In the Christian West the attitude to those whose interest centred on gathering money has been coloured by the teachings of the Church. From its point of view, both the miser and the usurer were guilty of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cool (aesthetic)
Coolness is an aesthetic of attitude, behavior, comportment, appearance, and style that is generally admired. Because of the varied and changing interpretation of what is considered "cool," as well as its subjective nature, the word has no single meaning. Coolness has associations of composure and self-control. When being used to describe something, it is often as an expression of admiration or approval. Although commonly regarded as slang, "cool" is widely used among disparate social groups and has endured in usage for generations. Overview There is no objective expression of coolness, as it varies wildly within cultures, ideologies, interests, and individuals. One consistent aspect, however, is that being cool is widely seen as desirable.Warren & Campbell, "What Makes Things Cool? How Autonomy Influences Perceived Coolness". Article by Caleb Warren and Margaret C. Campbell; ''Journal of Consumer Research'', Vol. 41, August 2014 Although there is no single concept nor objecti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
