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# random variables

Philosophy dictionary. . 2011.

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• Convergence of random variables — In probability theory, there exist several different notions of convergence of random variables. The convergence of sequences of random variables to some limit random variable is an important concept in probability theory, and its applications to …   Wikipedia

• Algebra of random variables — In the algebraic axiomatization of probability theory, the primary concept is not that of probability of an event, but rather that of a random variable. Probability distributions are determined by assigning an expectation to each random variable …   Wikipedia

• Exchangeable random variables — An exchangeable sequence of random variables is asequence X 1, X 2, X 3, ... of random variables such that for any finite permutation sigma; of the indices 1, 2, 3, ..., i.e. any permutation sigma; that leaves all but finitely many indices fixed …   Wikipedia

• Sum of normally distributed random variables — In probability theory, if X and Y are independent random variables that are normally distributed, then X + Y is also normally distributed; i.e. if :X sim N(mu, sigma^2),and :Y sim N( u, au^2),and X and Y are independent, then:Z = X + Y sim N(mu + …   Wikipedia

• Independent and identically-distributed random variables — IID or iid redirects here. For other uses, see: IID (disambiguation).In probability theory, a sequence or other collection of random variables is independent and identically distributed (i.i.d.) if each has the same probability distribution as… …   Wikipedia

• Taylor expansions for the moments of functions of random variables — In probability theory, it is possible to approximate the moments of a function f of a random variable X using Taylor expansions, provided that f is sufficiently differentiable and that the moments of X are finite. This technique is often used by… …   Wikipedia

• Random variable — A random variable is a rigorously defined mathematical entity used mainly to describe chance and probability in a mathematical way. The structure of random variables was developed and formalized to simplify the analysis of games of chance,… …   Wikipedia

• Random walk — A random walk, sometimes denoted RW, is a mathematical formalization of a trajectory that consists of taking successive random steps. The results of random walk analysis have been applied to computer science, physics, ecology, economics and a… …   Wikipedia

• Random matrix — In probability theory and mathematical physics, a random matrix is a matrix valued random variable. Many important properties of physical systems can be represented mathematically as matrix problems. For example, the thermal conductivity of a… …   Wikipedia

• Random sequence — A random sequence is a kind of stochastic process. In short, a random sequence is a sequence of random variables. Random sequences are essential in statistics. The statistical analysis of any experiment usually begins with the words let X 1,...,… …   Wikipedia