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Reciprocal Altruism Summary
Reciprocal may refer to: In mathematics * Multiplicative inverse, in mathematics, the number 1/''x'', which multiplied by ''x'' gives the product 1, also known as a ''reciprocal'' * Reciprocal polynomial, a polynomial obtained from another polynomial by reversing its coefficients * Reciprocal rule, a technique in calculus for calculating derivatives of reciprocal functions * Reciprocal spiral, a plane curve * Reciprocal averaging, a statistical technique for aggregating categorical data In science and technology * Reciprocal aircraft heading, 180 degrees (the opposite direction) from a stated heading * Reciprocal lattice, a basis for the dual space of covectors, in crystallography * Reciprocal length, a measurement used in science * Reciprocating engine or piston engine * Reciprocating oscillation in physical wave theory Life sciences and medicine * Hybrid (biology), in genetics, the result of a reciprocal pair of crossings, forming ''reciprocal hybrids'' * Reciprocal altru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiplicative Inverse
In mathematics, a multiplicative inverse or reciprocal for a number ''x'', denoted by 1/''x'' or ''x''−1, is a number which when Multiplication, multiplied by ''x'' yields the multiplicative identity, 1. The multiplicative inverse of a rational number, fraction ''a''/''b'' is ''b''/''a''. For the multiplicative inverse of a real number, divide 1 by the number. For example, the reciprocal of 5 is one fifth (1/5 or 0.2), and the reciprocal of 0.25 is 1 divided by 0.25, or 4. The reciprocal function, the Function (mathematics), function ''f''(''x'') that maps ''x'' to 1/''x'', is one of the simplest examples of a function which is its own inverse (an Involution (mathematics), involution). Multiplying by a number is the same as Division (mathematics), dividing by its reciprocal and vice versa. For example, multiplication by 4/5 (or 0.8) will give the same result as division by 5/4 (or 1.25). Therefore, multiplication by a number followed by multiplication by its reciprocal yiel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reciprocal Altruism
In evolutionary biology, reciprocal altruism is a behaviour whereby an organism acts in a manner that temporarily reduces its fitness while increasing another organism's fitness, with the expectation that the other organism will act in a similar manner at a later time. The concept was initially developed by Robert Trivers to explain the evolution of cooperation as instances of mutually altruistic acts. The concept is close to the strategy of "tit for tat" used in game theory. In 1987 Trivers told a symposium on reciprocity that he had originally submitted his article under the title "The Evolution of Delayed Return Altruism", but reviewer W. D. Hamilton suggested that he change the title to "The Evolution of Reciprocal Altruism". Trivers changed the title, but not the examples in the manuscript, which has led to confusion about what were appropriate examples of reciprocal altruism for the last 50 years. In their contribution to that symposium, Rothstein and Pierotti (1988) ad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reciprocal Public License
The Reciprocal Public License (RPL) is a copyleft software license released in 2001. Version 1.5 of the license was published on July 15, 2007, and was approved by the Open Source Initiative as an open-source license. Description The RPL was authored in 2001 by Scott Shattuck, a software architect for Technical Pursuit Inc. for use with that company's TIBET product line. The RPL was inspired by the GNU General Public License (GPL) and authored to explicitly remove what the RPL's authors have referred to as the GPL's "privacy loophole". The GPL privacy loopholes allows recipients of GPL'd code to: #make changes to source code which are never released to the open source community (by virtue of not deploying "to a third party"), and #derive financial or other business benefit from that action, violating what some might consider a simple concept of "fairness". Because of its " viral" nature, the RPL is often found in dual-licensing models in which it is paired with more traditio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reciprocal License
Copyleft is the legal technique of granting certain freedoms over copies of copyrighted works with the requirement that the same rights be preserved in derivative works. In this sense, ''freedoms'' refers to the use of the work for any purpose, and the ability to modify, copy, share, and redistribute the work, with or without a fee. Licenses which implement copyleft can be used to maintain copyright conditions for works ranging from computer software, to documents, art, scientific discoveries and even certain patents. Copyleft software licenses are considered ''protective'' or ''reciprocal'' in contrast with permissive free software licenses, and require that information necessary for reproducing and modifying the work must be made available to recipients of the software program, which are often distributed as binary executables. This information is most commonly in the form of source code files, which usually contain a copy of the license terms and acknowledge the authors of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reciprocal Construction
A reciprocal construction (abbreviated ) is a grammatical pattern in which each of the participants occupies both the role of agent and patient with respect to the other. An example is the English sentence ''John and Mary criticized each other'': John criticized Mary, and Mary criticized John. Reciprocal constructions can be said to express mutual relationships. Many languages, such as Semitic languages, Altaic languages or Bantu languages, have special reciprocal affixes in verbs. Other languages, including English, use reciprocal pronouns such as ''"each other"'' to indicate a mutual relation. Latin uses the preposition ''inter'' and its reflexive pronoun ''inter se'' (between themselves) when the verb is third person. Most Indo-European languages do not have special reciprocal affixes on verbs, and mutual relations are expressed through reflexive constructions or other mechanisms. For example, Russian reciprocal constructions have the suffix -sja (-ся, 'self'), which a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reciprocal Determinism
Reciprocal determinism is the theory set forth by psychologist Albert Bandura which states that a person's behavior both influences and is influenced by personal factors and the social environment. Bandura accepts the possibility that an individual's behavior may be conditioned through the use of consequences. At the same time he asserts that a person's behavior (and personal factors, such as cognitive skills or attitudes) can impact the environment. Bandura was able to show this when he created the Bandura's Box experiment. As an example, Bandura's reciprocal determinism could occur when a child is acting out in school. The child doesn't like going to school; therefore, they act out in class. This results in teachers and administrators of the school disliking having the child around. When confronted by the situation, the child admits they hate school and other peers don't like them. This results in the child acting inappropriately, forcing the administrators who dislike having t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sherrington's Law Of Reciprocal Innervation
René Descartes (1596–1650) was one of the first to conceive a model of reciprocal innervation (in 1626) as the principle that provides for the control of agonist and antagonist muscles. Reciprocal innervation describes skeletal muscles as existing in antagonistic pairs, with contraction of one muscle producing forces opposite to those generated by contraction of the other. For example, in the human arm, the triceps acts to extend the lower arm outward while the biceps acts to flex the lower arm inward. To reach optimum efficiency, contraction of opposing muscles must be inhibited while muscles with the desired action are excited. This reciprocal innervation occurs so that the contraction of a muscle results in the simultaneous relaxation of its corresponding antagonist. A common example of reciprocal innervation, is the effect of the nociceptive (or nocifensive) reflex, or defensive response to pain, otherwise commonly known as the withdrawal reflex; a type of involuntary act ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reciprocal Cross
In genetics, a reciprocal cross is a breeding experiment designed to test the role of parental sex on a given inheritance pattern. All parent organisms must be true breeding to properly carry out such an experiment. In one cross, a male expressing the trait of interest will be crossed with a female not expressing the trait. In the other, a female expressing the trait of interest will be crossed with a male not expressing the trait. It is the cross that could be made either way or independent of the sex of the parents. For example, suppose a biologist wished to identify whether a hypothetical allele Z, a variant of some gene A, is on the male or female sex chromosome. They might first cross a Z-trait female with an A-trait male and observe the offspring. Next, they would cross an A-trait female with a Z-trait male and observe the offspring. Via principles of dominant and recessive alleles, they could then (perhaps after cross-breeding the offspring as well) make an inference as to w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hybrid (biology)
In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different breeds, varieties, species or genera through sexual reproduction. Hybrids are not always intermediates between their parents (such as in blending inheritance), but can show hybrid vigor, sometimes growing larger or taller than either parent. The concept of a hybrid is interpreted differently in animal and plant breeding, where there is interest in the individual parentage. In genetics, attention is focused on the numbers of chromosomes. In taxonomy, a key question is how closely related the parent species are. Species are reproductively isolated by strong barriers to hybridisation, which include genetic and morphological differences, differing times of fertility, mating behaviors and cues, and physiological rejection of sperm cells or the developing embryo. Some act before fertilization and others after it. Similar barriers exist in plants, with differences in flowering tim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reciprocal Polynomial
In algebra, given a polynomial :p(x) = a_0 + a_1x + a_2x^2 + \cdots + a_nx^n, with coefficients from an arbitrary field, its reciprocal polynomial or reflected polynomial,* denoted by or , is the polynomial :p^*(x) = a_n + a_x + \cdots + a_0x^n = x^n p(x^). That is, the coefficients of are the coefficients of in reverse order. They arise naturally in linear algebra as the characteristic polynomial of the inverse of a matrix. In the special case where the field is the complex numbers, when :p(z) = a_0 + a_1z + a_2z^2 + \cdots + a_nz^n, the conjugate reciprocal polynomial, denoted , is defined by, :p^(z) = \overline + \overlinez + \cdots + \overlinez^n = z^n\overline, where \overline denotes the complex conjugate of a_i, and is also called the reciprocal polynomial when no confusion can arise. A polynomial is called self-reciprocal or palindromic if . The coefficients of a self-reciprocal polynomial satisfy for all . Properties Reciprocal polynomials have several connec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reciprocating Oscillation
Reciprocating motion, also called reciprocation, is a repetitive up-and-down or back-and-forth linear motion. It is found in a wide range of mechanisms, including reciprocating engines and pumps. The two opposite motions that comprise a single reciprocation cycle are called strokes. A crank can be used to convert into reciprocating motion, or conversely turn reciprocating motion into circular motion. For example, inside an internal combustion engine (a type of reciprocating engine), the expansion of burning fuel in the cylinders periodically pushes the piston down, which, through the connecting rod, turns the crankshaft. The continuing rotation of the crankshaft drives the piston back up, ready for the next cycle. The piston moves in a reciprocating motion, which is converted into circular motion of the crankshaft, which ultimately propels the vehicle or does other useful work. The reciprocating motion of a pump piston is close to, but different from, sinusoidal simple harmon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
