hawk

Sranan Tongo: aka

From Middle English hauk, hauke, hawke, havek, from Old English hafoc (“hawk”), from Proto-West Germanic *habuk, from Proto-Germanic *habukaz, controversially derived from Proto-Indo-European *kopuǵos, perhaps ultimately derived from *keh₂p- (“seize”).
See also West Frisian hauk, German Low German Haavke, Dutch havik, German Habicht, Swedish hök, Danish høg, Norwegian Bokmål hauk, Norwegian Nynorsk hauk, Faroese heykur, Icelandic haukur, Finnish haukka, Estonian haugas; also Latin capys, capus (“bird of prey”), Albanian gabonjë, shkabë (“eagle”), Russian ко́бец (kóbec, “falcon”), Polish kobuz (“Eurasian Hobby”)).

(game theory) An uncooperative or purely selfish participant in an exchange or game, especially when untrusting, acquisitive or treacherous. Refers specifically to the prisoner's dilemma, a.k.a. the Hawk-Dove game.


core

en-noun

core (countable and uncountable, plural cores)

desc

Translingual: core eudicots, core Malvales

From Middle English core, kore, coor (“apple-core, pith”), of obscure and uncertain origin. Possibly of native English origin, from Old English *cor, related to Old English *coruc, *corc (diminutive) (> Middle English cork, crok (“core of an apple or other fruit, heart of an onion”)) and Old English corn (“seed", also "grain”); or alternatively perhaps from Old French cuer (“heart”), from Latin cor (“heart”); or from Old French cors (“body”), from Latin corpus (“body”). Compare also Middle English colk, coke, coll (“the heart or centre of an apple or onion, core”), Dutch kern (“core”), German Kern (“core”). See also heart, corpse.

unc

obscure and uncertain

non-rhotic, without the horse–hoarse merger

The most important part of a thing or aggregate of things wherever located and whether of any determinate location at all; the essence.

A technical term for classification of things denoting those parts of a category that are most easily or most likely understood as within it.

(game theory) The set of feasible allocations that cannot be improved upon by a subset (a coalition) of the economy's agents.


focal point

(game theory) A solution that people will tend to use in the absence of communication, because it seems natural, special, or relevant.


imputation

en-noun

imputation (countable and uncountable, plural imputations)

From Middle French imputation, from Latin imputatio.

(game theory) A distribution that is efficient and individually rational.


zero-sum game

Dalio is right, but somewhat self-serving. If hedge-fund managers are playing a zero-sum game, what is their social utility? […] Can it really be in America’s interest to have so much of its young talent playing a zero-sum game?

2011 July 18, John Cassidy, “Mastering the Machine”, in The New Yorker, →ISSN:

A zero-sum game, as its name suggests, is one in which, whatever the outcome, the payoffs to the players add up to zero, which means that what one player gains, the other(s) must necessarily lose.

2013, Andrew M. Colman, Game Theory and its Applications: In the Social and Biological Sciences, Psychology Press, →ISBN, page 55:

Listen, I know it's been hard / You know it’s no different for me / We’re less than a zero-sum game now / And baby, we both know that's not how it's supposed to be

2014, “The Writing's On the Wall”, in Hungry Ghosts, performed by OK Go:

He said turning a lab-created animal into a wild population would be an “enormous challenge”, but the financial support for de-extinction research should not be seen as a “zero sum game”.

2022 August 16, Adam Morton, “De-extinction: scientists are planning the multimillion-dollar resurrection of the Tasmanian tiger”, in The Guardian:

On the flight home after their first talks, a deflated Merkel concluded that Trump “looked at everything like the real estate developer he was before he entered politics” – as a zero-sum game.

2024 November 21, Deborah Cole, “Merkel: I mistook Trump for ‘someone completely normal’”, in The Guardian, →ISSN:

(game theory) A game (or a similar political or economic system) in which the gains of some players must equal the losses of others.

零和博弈

system in which one player's winnings must equal losses of others


battle of the sexes

battle of the sexes (plural battles of the sexes)

(game theory) A situation in which two people want to do different things, but do them together.


negative-sum

(game theory) of a situation in which there is a net loss


strictly better

(game theory, of a strategy) That leads to a better outcome no matter what the other player does.


kingmaker

LL-Q1860 (eng)-I learned some phrases-kingmaker.wav

/ˈkɪŋˌmeɪkɚ/

Richard Neville, 16th Earl of Warwick
Tewkesbury Abbey
Wars of the Roses

From king + maker, originally used in the 16th century in “Warwick the Kingmaker”, an epithet of Richard Neville, 16th Earl of Warwick (1428–1471), a key figure in the Wars of the Roses whose actions led to King Henry VI being deposed in 1461 and Edward IV appointed in his place, then Edward IV being replaced by Henry VI again in 1470.

(by extension, game theory) A player who is unable to win but powerful enough to decide which of the other viable players will eventually win.


payoff function

payoff function (plural payoff functions)

(game theory) A mathematical function describing the award given to a single player at the outcome of a game.


utility function

utility function (plural utility functions)

(game theory) A mathematical function that assigns a real number to every element of the outcome space in a way that captures the agent's preferences over both simple and compound lotteries.


common knowledge

(logic, game theory) A special kind of knowledge for a group of agents, such that when all the agents in a group G know p, they all know that they know p, they all know that they all know that they know p, and so on ad infinitum.


Nash equilibrium

Nash equilibrium (plural Nash equilibria)

Named after American mathematician John Forbes Nash Jr.

named-after

(game theory) The set of choices of players' strategies for which no player can benefit by changing his or her strategy assuming that the other players keep theirs unchanged.


Pareto improvement

en-noun

Pareto improvement (plural Pareto improvements)

Pareto improvements (plural)
Pareto-improvement (alternative)

(game theory, economics) A change in the allocation of a resource to a set of individuals that is an improvement for at least one and no worse for any other.


Pareto efficient

en-adj

Pareto efficient (comparative more Pareto efficient, superlative most Pareto efficient)

more Pareto efficient (comparative)
most Pareto efficient (superlative)

(game theory, economics) Describing a situation in which the profit of one party cannot be increased without reducing the profit of another.


Pareto optimal

(game theory) Describing a strategy that cannot be made to perform better against one opposing strategy without performing less well against another.


Shapley value

Named in honour of Lloyd Shapley, who introduced it in 1953.

ϕᵢ(v)=∑_(S⊆N⧵i)(|S|!;(n-|S|-1)!)/(n!)(v(S∪i)-v(S)),

given a coalitional game with a set N of n players and a worth function v;:;𝒫(N);→ℜ.

(game theory) A real number determined for the player i as


normal form game

en-noun

normal form game (plural normal form games)

(game theory) Formally, a structure (P, mathbf S, mathbf F) where P = {1,2, ...,m} is a set of players, mathbf S=(S_1,S_2,…,S_m) is an m-tuple of pure strategy sets, one for each player, and mathbf F=(F_1,F_2,…,F_m) is an m-tuple of payoff functions.


extensive form game

extensive form game (plural extensive form games)

(game theory) Informally, a representation of a game as a tree of decision nodes, with the game beginning at a unique initial node, and flowing through the tree along a path determined by the players until a terminal node is reached, where play ends and payoffs are assigned to all players; each non-terminal node belongs to a player; that player chooses among the possible moves at that node, each possible move is an edge leading from that node to another node.


cooperative game

cooperative game (plural cooperative games)

characteristic function
characteristic function

(game theory) Informally, a game formalized using a function (called the characteristic function) that assigns to each coalition of players a real number representing the payoff that the coalition can gain if it is formed, without specifying how the outcome is divided among the participants of the coalition; upon the execution of the game, each player can be a member of at most one coalition.


diverter

The diverter clearly gains from a successful diversion but pays a heavy price if caught.

2012, Morton D. Davis, Game Theory: A Nontechnical Introduction, page 47:

The game theory also requires a precise statement of all the conceivable moves the diverter might make and counter-moves available to the defender.

1980, LBL Newsmagazine, volumes 5-9, page 20:

(game theory) One who uses diversionary tactics.


minimax

(decision theory, game theory) A decision rule used for minimizing the maximum possible loss, or maximizing the minimum gain.


maximin

(decision theory, game theory) A rule to identify the worst outcome of each possible option to find one's best (maximum payoff) play.


backward induction

backward induction (usually uncountable, plural backward inductions)

Simple game theory tells us that a process of backward induction should, really, at some point, induce the smart money to get out. And were that to happen, investors really should be prepared to lose everything.

2021 December 14, Richard Partington, quoting Thomas Belsham, “Bitcoin could become ‘worthless’, Bank of England warns”, in The Guardian:

(game theory) The process of reasoning backwards in time, from the end of a problem or situation, to determine a sequence of optimal actions.


saddle point

(game theory) Such a point in the graphical representation of the possible outcomes of a game.


normal form

(game theory) A matrix that represents the possible outcomes of a game

normaalimuoto

game theory: matrix of possible outcomes


subgame

LL-Q1860 (eng)-Flame, not lame-subgame.wav

A subgame is a piece of a game—the piece that remains to be played beginning at any point at which the complete history of the game thus far is common knowledge among the players.

1992, Robert Gibbons, A Primer in Game Theory, Prentice-Hall, page 94:

(game theory) A subset of a game that can be considered a game in its own right.


kayles

From Middle English keyles, plural of Middle English keyle (see Dutch kegel, German Kegel, Danish kegle, and Swedish kegla).

(uncountable, game theory) A simple impartial game in combinatorial game theory, in which players take turns to knock out one pin or two adjacent pins from a line of imagined bowling pins.


truel

To effect a yet more complex and challenging truel, we can void the simplification that each player knows his order of firing ab initio.

2014, Richard A. Epstein, The Theory of Gambling and Statistical Logic, Gulf Professional Publishing, →ISBN, page 324:

(game theory) A duel fought between three people.


positive-sum

Morality […] is a consequence of the interchangeability of perspectives and the opportunity the world provides for positive-sum games.

2011, Steven Pinker, The Better Angels of Our Nature, Penguin, published 2012, page 220:

(game theory) Pertaining to a game or situation where overall benefits to all participants can increase.


Sir Philip Sidney game

Sir Philip Sidney game (plural Sir Philip Sidney games)

Named after a story about Sir Philip Sidney, who allegedly, when fatally wounded, gave his water to another, saying, "Thy necessity is greater than mine."

(biology, game theory) A model for the evolution and maintenance of informative communication between relatives, developed to explain begging behaviour in chicks.

Sir Philip Sidney
Sir Philip Sidney game


Schelling point

Schelling point (plural Schelling points)

The concept was introduced by American economist Thomas Schelling in his book The Strategy of Conflict (1960).


parity game

(game theory) A type of game played on a directed graph whose nodes are coloured by priority.


Grundy number

Named after P. M. Grundy, who studied an analogous concept for directed graphs in 1939.


strategyproof

(game theory) Of an asymmetric game where players have private information: such that there is no incentive for any of the players to hide or lie about their private information from the other players.


hyperfair

Meanwhile, selection strongly favored responders that accepted fair or hyperfair offers.

2015 July 31, “Rational Constraints and the Evolution of Fairness in the Ultimatum Game”, in PLOS ONE, →DOI:

(game theory) Excessively fair, typically describing an offer involving more than fifty percent of the stake.


antigame

The principle is the same as in kicking the provocative boxer or using strategic weapons in response to a tactical nuclear challenge. A strategy designed for refusing to play a game might be called an antigame strategy.

1962, Klaus Eugen Knorr, Limited strategic war:

When capacity to respond to any aggression at a corresponding level of violence does not exist, the strategy of antigame is recommended.

1966, Y. Harkabi, Nuclear War and Nuclear Peace, Transaction Publishers, →ISBN, page 105:

Should either side adopt an uncooperative or "antigame" stance and attempt to destroy its opponent's high command, then the strategy defeats itself and the side that attempted to maintain communications and hold the door open for war termination is disadvantaged.

1988, Stephen J. Cimbala, Rethinking Nuclear Strategy, Scholarly Resources, Incorporated:

(game theory) A strategy in which a player refuses to participate in a game or replaces it with a game with different rules.


evolutionarily stable strategy

evolutionarily stable strategy (plural evolutionarily stable strategies)

evolutionarily stable strategies (plural)
evolutionary stable strategy (alternative)

Coined by British biologist John Maynard Smith in 1972 in his paper Game Theory and The Evolution of Fighting.

coin

1986 John Maynard Smith: Evolution and the Theory of Games. Cambridge University Press
In this chapter, I introduce the concept of an "evolutionarily stable strategy", or ESS. A 'strategy' is a behavioural phenotype; i.e. it is a specification of what an individual will do in any situation in which it may find itself. An ESS is a strategy such that, if all the members of a population adopt it, then no mutant strategy could invade the population under the influence of natural selection. The concept is couched in terms of a "strategy" because it arose in the context of animal behaviour. The idea, however, can be applied equally well to any kind of phenotypic variation, and the word strategy could be replaced by the word phenotype; for example, a strategy could be the growth form of a plant, or the age at first reproduction, or the relative numbers of sons and daughters produced by a parent.

To be an evolutionarily stable strategy, remember, a strategy must not be invadable, when it is common, by a rare mutant strategy.

1976, Richard Dawkins, The Selfish Gene:

An evolutionarily stable strategy is a strategy that does well against copies of itself.

(evolutionary theory, game theory) A strategy that, when adopted by a population, is effective and not foreseeably likely to be replaced by another strategy.


semivalue

(game theory) A function on a vector space of all coalitional games which verifies linearity, anonymity, positivity, and inessential games.


dollar auction

Among the most terrifying of all dollar auctions followed World War II, when the United States and the Soviet Union entered into an arms race to produce more sophisticated and destructive weapons.

2012, Robert Dodge, Schelling's Game Theory: How to Make Decisions, page 117:

(game theory) A non-zero-sum sequential game designed to illustrate a paradox brought about by traditional rational-choice theory in which players are compelled to make an ultimately irrational decision based entirely on a sequence of apparently rational choices made throughout the game. It involves an auction for a dollar bill where the second-highest bidder loses the amount that they bid, making them the biggest loser in the auction.


Parrondo's paradox

(game theory) The paradox whereby a combination of losing strategies (such as alternating between two games that each, played individually, would result in an overall loss) may give a winning strategy.


Bondareva-Shapley theorem

Formulated independently by Olga Bondareva and Lloyd Shapley in the 1960s.

(game theory) A theorem that describes a necessary and sufficient condition for the non-emptiness of the core of a cooperative game in characteristic function form. The game's core is non-empty if and only if the game is balanced.


hyperfairness

(game theory) The property of being hyperfair.


fair division

(mathematics, economics, game theory) the problem of dividing a set of resources among several people who have an entitlement to them, such that each person receives their due share


fair cake-cutting

(game theory) A kind of fair division problem in which there is a divisible heterogeneous resource that must be divided among several partners in a subjectively fair way.


divide and choose

(game theory) a procedure for envy-free fair cake-cutting in which one person divides a heterogeneous resource in two and the other person chooses one of those two


cut and choose

divide and choose
divide and choose#English

(game theory) Synonym of divide and choose.


winner's curse

(auctions, game theory) The phenomenon whereby the winner of an auction is likely to overpay, since each bid represents a bidder's estimate of the item's value, and one would expect the average bid to be the most accurate.


Zermelo's theorem

Ernst Zermelo
Zermelo's theorem
Zermelo's theorem (game theory)

(game theory) A theorem about finite two-person games of perfect information in which the players move alternately and chance does not affect the decision-making process. It states that if the game cannot end in a draw, then one of the two players must have a winning strategy, i.e. force a win.


preplay

a preplay negotiation period


gametype

Many varieties of gametype exist and are in use in popular and obscure games – but as we explore the issue of virtual worlds, it's only really the gametypes that use some form of 'interactive fiction' that concern us.

2011, Woody Evans, Information Dynamics in Virtual Worlds: Gaming and Beyond, page 27:

For each parameter value of a we distinguish four different gametypes. The setup of the experiment was designed in such a way that each player played four times each of the four possible gametypes (H,H), (H,L), (L,H), and (L,L), […]

2012, Bettina Kuon, Two-Person Bargaining Experiments with Incomplete Information, page 65:


centipede game

(game theory) An extensive form game in which two players take turns choosing either to take a slightly larger share of an increasing pot, or to pass the pot to the other player. The payoffs are arranged so that if one passes the pot to one's opponent and the opponent takes the pot on the next round, one receives slightly less than if one had taken the pot on this round, but after an additional switch the potential payoff will be higher. Therefore, although at each round a player has an incentive to take the pot, it would be better for them to wait.


hypergame

Now, the first move of hypergame is to state which normal game is to be played. For example, if you and I were playing hypergame and I had the first move, I might say, “Let's play chess.”

1983, Raymond Smullyan, Five Thousand B.C. and Other Philosophical Fantasies:

Using this approach, hypergame analysis has been applied to business, water resources, and military conflicts.

2009, Keith William Hipel, Conflict Resolution - Volume II, page 169:

In a hypergame situation each player behaves as an autonomous agent who makes a decision based on his own "internal model" that describes individually and independently the complex situation where he is involved.

2013, Hessam S. Sarjoughian, Francois E. Cellier, Discrete Event Modeling and Simulation Technologies:

A hypergame models the situation where different players perceive their interaction with other players differently and consequently play different games in their own minds depending on their perception.

2021, Charles A. Kamhoua, Christopher D. Kiekintveld, Fei Fang, Game Theory and Machine Learning for Cyber Security, page 102:

(game theory) A game that is played by a player based on their own knowledge of game states and their perception of other players' knowledge of game states.


grim trigger

(game theory) A strategy that always cooperates as long as the opponent does not defect, in which case thereafter the strategy always defects.


dynamic inconsistency

(economics, game theory) A situation in which a decision maker's preferences change over time in such a way that a preference can become inconsistent at another point in time.


IPD

en-noun

IPD (countable and uncountable, plural IPDs)

iterated prisoner's dilemma
iterated prisoner's dilemma#English

(game theory) Initialism of iterated prisoner's dilemma.


economic equilibrium

economic equilibrium (plural economic equilibriums or economic equilibria)

economic equilibriums (plural)
economic equilibria (plural)

(game theory) A situation where economic forces are balanced, and without external influences, the value of economic variables will not change.


maxipok

(game theory, philosophy) A strategy that aims to maximise the probability of an acceptable outcome.