6,052 articles
Angle bisector theorem
The angle bisector theorem states that the bisector of an angle in a triangle divides the opposite side in the ratio of the two adjacent sides.
Annals of Statistics
The Annals of Statistics is a bimonthly peer-reviewed statistics journal published by the Institute of Mathematical Statistics since 1973, traditionally ranked among the four leading statistics journals.
Anonymous function
An anonymous function, also called a function literal, is a function definition that is not bound to an identifier, usable inline as a value in languages like Python and JavaScript.
ANOVA gauge R&R
ANOVA gauge R&R (also ANOVA Gage R&R) is a method for gauge repeatability and reproducibility studies that estimates measurement variability by fitting an ANOVA model with parts and operators as factors.
Anscombe's quartet
Anscombe's quartet is a set of four small datasets constructed by statistician Francis J. Anscombe in 1973, sharing nearly identical summary statistics while their scatter plots show completely different patterns.
Antennae search algorithm
The antennae search algorithm, usually called beetle antennae search (BAS), is a beetle-inspired metaheuristic for continuous optimization that iterates a single candidate solution, reported by Jiang and Li in 2018.
Anthony J. Kearsley
Anthony José Kearsley is an American research mathematician at NIST who develops large-scale numerical optimization methods for solving partial differential equations, and received the 1998 PECASE award.
Antichain
An antichain is a subset of a partially ordered set in which no two distinct elements are comparable; its maximum size is called the poset's width.
Antiderivative
An antiderivative, also called an indefinite integral, is a differentiable function F whose derivative F′ equals a given function f; any two antiderivatives differ only by a constant C.
Antonim
Antonim is an impartial combinatorial game, a variant of Nim in which no two heaps may have the same size, changing the legal positions and the winning strategy.
Anytime-valid inference
Anytime-valid inference, also called safe anytime-valid inference (SAVI), is a statistical framework using e-processes and confidence sequences whose error guarantees hold at any stopping time, useful in A/B testing.
AP Calculus
AP Calculus, or Advanced Placement Calculus, is the Advanced Placement program's pair of high school courses, AB and BC, that can earn students college credit or advanced placement.
APACHE II
APACHE II (Acute Physiology and Chronic Health Evaluation II) is a severity scoring system for critically ill ICU patients, published in 1985 by Knaus and colleagues.
Aperiodic tiling
An aperiodic tiling, or aperiodic tessellation, is a nonperiodic tiling of the plane containing no arbitrarily large periodic patches, best exemplified by Roger Penrose's tiles.
Apéry's constant
Apéry's constant, the value of the Riemann zeta function at 3, equals about 1.2020569 and is the sum of the reciprocals of the cubes of the positive integers.
Applications of martingales
Applications of martingales, via the optional stopping theorem, prove betting systems fail in unfavorable games, give gambler's ruin probabilities and game durations, and power Wald's sequential probability ratio test.
Applications of p-adic numbers
Applications of p-adic numbers are uses of p-adic number systems outside core p-adic analysis, in physics, cryptography and coding theory, data analysis, and dynamical systems, dating to 1987.
Applied mathematics
Applied mathematics, also called applied math or applied maths, is the branch of mathematics that develops and applies mathematical tools to problems in science, engineering, industry, and society.
Approximate Bayesian computation
Approximate Bayesian computation, also known as likelihood-free inference, is a family of simulation-based statistical methods that estimates posterior distributions by comparing simulated data with observed data, without evaluating a likelihood function.
Approximate message passing
Approximate message passing (AMP) is a class of iterative algorithms for high-dimensional statistical estimation, introduced for compressed sensing in 2009, whose error is exactly predicted by state evolution.
Approximation error
Approximation error is the difference between an exact mathematical quantity and its approximation, arising in numerical computation and split into truncation error and roundoff error.
Approximation property
The approximation property (AP) is a property of Banach spaces stating that the identity operator can be approximated uniformly on compact sets by finite-rank operators.
Approximations of π
Approximations of π, also called numerical approximations of pi, are values used in place of π, from Archimedes' 22/7 around 250 BC to a 2025 record of 314 trillion digits.
Arakelov theory
Arakelov theory, also called Arakelov geometry, is an intersection theory on arithmetic varieties introduced by Suren Arakelov in 1974 and extended by Gillet and Soulé in 1990.
Arb (software)
Arb is a C library for arbitrary-precision real and complex arithmetic that tracks numerical errors using ball arithmetic, created by Fredrik Johansson and merged into FLINT in 2023.
Arbitrary-precision arithmetic
Arbitrary-precision arithmetic, also known as bignum arithmetic, is computation on numbers whose precision is limited only by machine memory, supporting integers, rationals, and floats in cryptography, computer algebra, and record calculations.
Arc routing
Arc routing is a class of combinatorial optimization problems seeking minimum-cost routes that traverse a network's edges rather than visit its nodes, as in snowplowing and mail delivery.
Archetypal analysis
Archetypal analysis is a statistical matrix factorization method that represents each data point as a convex mixture of extreme points called archetypes, introduced by Cutler and Breiman in 1994.
Archimedean copula
An Archimedean copula is a copula constructed from a single univariate generator function, popular in applied work for its analytic tractability, with families like Clayton, Gumbel, and Frank.
Archimedean property
The Archimedean property, also known as Eudoxus' axiom, is a property of ordered fields stating that no element exceeds every natural number; Archimedes stated it in On the Sphere and Cylinder.