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Counterexample

In logic, a counterexample is an exception to a proposed general rule or law, and often appears as an example which disproves a universal statement. For example, the statement "all students are lazy" is a universal statement which makes the claim ...

Covering cherub

Covering cherub is the obstructing presence for the artist of the inherited tradition, and cultural predecessors, with which they are faced.

Descriptive interpretation

According to Rudolf Carnap, in logic, an interpretation is a descriptive interpretation if at least one of the undefined symbols of its formal system becomes, in the interpretation, a descriptive sign. In his Introduction to Semantics he makes a ...

Interpretations of quantum mechanics

An interpretation of quantum mechanics is an attempt to explain how the mathematical theory of quantum mechanics "corresponds" to reality. Although quantum mechanics has held up to rigorous and extremely precise tests in an extraordinarily broad ...

Michael Krausz

Michael Krausz is a Swiss-born American philosopher as well as an artist and orchestral conductor. His philosophical works focus on the theory of interpretation, theory of knowledge, philosophy of science, philosophy of history, and philosophy of ...

Philosophical interpretation of classical physics

Classical Newtonian physics has, formally, been replaced by quantum mechanics on the small scale and relativity on the large scale. Because most humans continue to think in terms of the kind of events we perceive in the human scale of daily life, ...

Valuation (logic)

In logic and model theory, a valuation can be: In propositional logic, an assignment of truth values to propositional variables, with a corresponding assignment of truth values to all propositional formulas with those variables. In first-order lo ...

Actuarial Society of South Africa HIV/AIDS models

The Actuarial Society of South Africa HIV/AIDS models, also known as ASSA AIDS models, are a series of mathematical models developed to assist the actuarial profession and the Actuarial Society of South Africa in assessing and addressing the impa ...

AIMMS

AIMMS is a prescriptive analytics software company with offices in the Netherlands, United States, China and Singapore. It has two main product offerings that provide modeling and optimization capabilities across a variety of industries. The AIMM ...

Analytica (software)

Analytica is a visual software package developed by Lumina Decision Systems for creating, analyzing and communicating quantitative decision models. It combines hierarchical influence diagrams for visual creation and view of models, intelligent ar ...

Apparent infection rate

Apparent infection rate is an estimate of the rate of progress of a disease, based on proportional measures of the extent of infection at different times. Firstly, a proportional measure of the extent of infection is chosen as the disease extent ...

Arditi–Ginzburg equations

The Arditi–Ginzburg equations describes ratio dependent predator–prey dynamics. Where N is the population of a prey species and P that of a predator, the population dynamics are described by the following two equations: d N d t = f N − g N P d P ...

Automated efficiency model

An automated efficiency model is a mathematical model that estimates a real estate property’s efficiency by using details specific to the property which are available publicly and/or housing characteristics which are aggregated over a given area ...

Backtesting

Backtesting is a term used in modeling to refer to testing a predictive model on historical data. Backtesting is a type of retrodiction, and a special type of cross-validation applied to previous time period.

Boolean delay equation

As a novel type of semi-discrete dynamical systems, Boolean delay equations are models with Boolean-valued variables that evolve in continuous time. Since at the present time, most phenomena are too complex to be modeled by partial differential e ...

Boolean model of information retrieval

The Boolean model of information retrieval is a classical information retrieval model and, at the same time, the first and most-adopted one. It is used by many IR systems to this day. The BIR is based on Boolean logic and classical set theory in ...

Bounded growth

Bounded growth occurs when the growth rate of a mathematical function is constantly increasing at a decreasing rate. Asymptotically, bounded growth approaches a fixed value. This contrasts with exponential growth, which is constantly increasing a ...

Breath gas analysis

Breath gas analysis is a method for gaining information on the clinical state of an individual by monitoring volatile organic compounds present in the exhaled breath. Exhaled breath is naturally produced by the human body through expiration and t ...

Bueno-Orovio–Cherry–Fenton model

The Bueno-Orovio–Cherry–Fenton model, also simply called Bueno-Orovio model, is a minimal ionic model for human ventricular cells. It belongs to the category of phenomenological models, because of its characteristic of describing the electrophysi ...

Calculus of voting

Calculus of voting refers to any mathematical model which predicts voting behaviour by an electorate, including such features as participation rate. A calculus of voting represents a hypothesized decision-making process. These models are used in ...

Cebeci–Smith model

The Cebeci–Smith model is a 0-equation eddy viscosity model used in computational fluid dynamics analysis of turbulent boundary layer flows. The model gives eddy viscosity, μ t {\displaystyle \mu _{t}}, as a function of the local boundary layer v ...

The Chemical Basis of Morphogenesis

The Chemical Basis of Morphogenesis is an article written by the English mathematician Alan Turing in 1952 describing the way in which natural patterns such as stripes, spots and spirals may arise naturally out of a homogeneous, uniform state. Th ...

Chemical reaction model

Chemical reaction models transform physical knowledge into a mathematical formulation that can be utilized in computational simulation of practical problems in chemical engineering. Computer simulation provides the flexibility to study chemical p ...

Classical control theory

Classical control theory is a branch of control theory that deals with the behavior of dynamical systems with inputs, and how their behavior is modified by feedback, using the Laplace transform as a basic tool to model such systems. The usual obj ...

Color model

A color model is an abstract mathematical model describing the way colors can be represented as tuples of numbers, typically as three or four values or color components. When this model is associated with a precise description of how the componen ...

Compartmental modelling of dendrites

Compartmental modelling of dendrites deals with multi-compartment modelling of the dendrites, to make the understanding of the electrical behavior of complex dendrites easier. Basically, compartmental modelling of dendrites is a very helpful tool ...

Complex system

A complex system is a system composed of many components which may interact with each other. Examples of complex systems are Earths global climate, organisms, the human brain, infrastructure such as power grid, transportation or communication sys ...

Computational model

A computational model is a mathematical model in computational science that requires extensive computational resources to study the behavior of a complex system by computer simulation. The system under study is often a complex nonlinear system fo ...

Cumulative accuracy profile

The cumulative accuracy profile is used in data science to visualize the discriminative power of a model. The CAP of a model represents the cumulative number of positive outcomes along the y -axis versus the corresponding cumulative number of a c ...

Deterministic simulation

In mathematical modeling, deterministic simulations contain no random variables and no degree of randomness, and consist mostly of equations, for example difference equations. These simulations have known inputs and they result in a unique set of ...

Effective selfing model

The effective selfing model is a mathematical model that describes the mating system of a plant population in terms of the degree of self-fertilisation present. It was developed in the 1980s by Kermit Ritland, as an alternative to the simplistic ...

Electoral Calculus

Electoral Calculus is a political forecasting web site which attempts to predict future United Kingdom general election results. It considers national factors but excludes local issues.

Empirical modelling

This article deals with the use of the term in computer science. For the use in economics, see Econometric model. For uses in other contexts, see Types of scientific modeling. Empirical modelling refers to any kind of modelling based on empirical ...

Equation-free modeling

Equation-free modeling is a method for multiscale computation and computer-aided analysis. It is designed for a class of complicated systems in which one observes evolution at a macroscopic, coarse scale of interest, while accurate models are onl ...

Excitable medium

An excitable medium is a nonlinear dynamical system which has the capacity to propagate a wave of some description, and which cannot support the passing of another wave until a certain amount of time has passed. A forest is an example of an excit ...

Exponential growth

Exponential growth is a specific way that a quantity may increase over time. It occurs when the instantaneous rate of change of a quantity with respect to time is proportional to the quantity itself. Described as a function, a quantity undergoing ...

Extended Mathematical Programming

Algebraic modeling languages like AIMMS, AMPL, GAMS, MPL and others have been developed to facilitate the description of a problem in mathematical terms and to link the abstract formulation with data-management systems on the one hand and appropr ...

Fractional-order system

In the fields of dynamical systems and control theory, a fractional-order system is a dynamical system that can be modeled by a fractional differential equation containing derivatives of non-integer order. Such systems are said to have fractional ...

Generalised logistic function

The generalised logistic function or curve, also known as Richards curve, originally developed for growth modelling, is an extension of the logistic or sigmoid functions, allowing for more flexible S-shaped curves: Y t = A + K − A C + Q e − B t 1 ...

Global cascades model

Global cascades models are a class of models aiming to model large and rare cascades that are triggered by exogenous perturbations which are relatively small compared with the size of the system. The phenomenon occurs ubiquitously in various syst ...

Grey box model

In mathematics, statistics, and computational modelling, a grey box model combines a partial theoretical structure with data to complete the model. The theoretical structure may vary from information on the smoothness of results, to models that n ...

History of network traffic models

Design of robust and reliable networks and network services relies on an understanding of the traffic characteristics of the network. Throughout history, different models of network traffic have been developed and used for evaluating existing and ...

Landscape evolution model

A landscape evolution model is a physically based numerical model that simulates changing terrain over the course of time. This can be due to glacial erosion and deposition; erosion, sediment transport, and deposition in fluvial systems such as r ...

Linear seismic inversion

Inverse modeling is a mathematical technique where the objective is to determine the physical properties of the subsurface of an earth region that has produced a given seismogram. Cooke and Schneider defined it as calculation of the earths struct ...

LINGO (mathematical modeling language)

LINGO is a mathematical modeling language designed for formulating and solving optimization problems, including linear, integer, and nonlinear programming problems.

Logan plot

A Logan plot is a graphical analysis technique based on the compartment model that uses linear regression to analyze pharmacokinetics of tracers involving reversible uptake. It is mainly used for the evaluation of nuclear medicine imaging data af ...

Lotka–Volterra equations

The Lotka–Volterra equations, also known as the predator–prey equations, are a pair of first-order nonlinear differential equations, frequently used to describe the dynamics of biological systems in which two species interact, one as a predator a ...

Maas–Hoffman model

The Maas–Hoffman model is a mathematical tool to characterize the relation between crop production and soil salinity. It describes the crop response by a broken line of which the first part is horizontal and the second is sloping downward. The br ...

Macroscopic traffic flow model

A Macroscopic traffic flow model is a mathematical traffic model that formulates the relationships among traffic flow characteristics like density, flow, mean speed of a traffic stream, etc. Such models are conventionally arrived at by integratin ...

MAgPIE

MAgPIE is a non-linear, recursive, dynamic-optimization, global land and water-use model with a cost-minimization objective function. MAgPIE was developed and is employed by the land-use group working at the Potsdam Institute for Climate Impact R ...