What you don’t know won’t hurt me: Costly (but quiet) exit in dictator games

We used simple economic games to examine pro-social behavior and the lengths that people will take to avoid engaging in it. Over two studies, we found that about one-third of participants were willing to “exit” a $10 dictator game and take $9 instead. The exit option left the receiver nothing, but also ensured that the receiver never knew that a dictator game was to be played. Because most social utility models are defined over monetary outcomes, they cannot explain choosing the ($9, $0) exit outcome over the dominating $10 dictator game, since the game includes outcomes of ($10, $0) and ($9, $1). We also studied exiting using a “private” dictator game. In the private game, the receiver never knew about the game or from where any money was received. Gifts in this game were added innocuously to a payment for a separate task. Almost no dictators exited from the private game, indicating that receivers’ beliefs are the key factor in the decision to exit. When, as in the private game, the receivers’ beliefs and expectations cannot be manipulated by exit, exit is seldom taken. We conclude that giving often reflects a desire not to violate others’ expectations rather than a concern for others’ welfare per se. We discuss the implications of our results for understanding ethical decisions and for testing and modeling social preferences. An adequate specification of social preferences should include “psychological” payoffs that directly incorporate beliefs about actions into the utility function.     

Radical Semantics: A New Theory of Meaning

This paper extends Parikh’s earlier work in semantics with games of partial information and attempts to derive and represent the full content of an utterance from first principles. It also discusses various ways in which this content may be indeterminate.     

Getting less than their fair share: Maltreated youth are hyper‐cooperative yet vulnerable to exploitation in a public goods game

Human cooperative behavior has long been thought to decline under adversity. However, studies have primarily examined perceived patterns of cooperation, with little eye to actual cooperative behavior embedded within social interaction. Game‐theoretical paradigms can help close this gap by unpacking subtle differences in how cooperation unfolds during initial encounters. This study is the first to use a child‐appropriate, virtual, public goods game to study actual cooperative behavior in 329 participants aged 9–16 years with histories of maltreatment (n = 99) and no maltreatment (n = 230) while controlling for psychiatric symptoms. Unlike work on perceived patterns of cooperation, we found that maltreated participants actually contribute more resources to a public good during peer interaction than their nonmaltreated counterparts. This effect was robust when controlling for psychiatric symptoms and peer problems as well as demographic variables. We conclude that maltreatment may engender a hyper‐cooperative strategy to minimize the odds of hostility and preserve positive interaction during initial encounters. This, however, comes at the cost of potential exploitation by others.     

博弈论视角下的超扫描多人互动任务新模型

超扫描指同时记录多个被试脑活动, 以探索其社会互动脑机制的研究手段。从博弈论视角, 可区分超扫描任务中的冲突、合作与协作三类任务, 分离已有研究中未严格界定的“协作”与“合作”概念, 为超扫描研究的多人互动范式建立新模型。任务所包含协作因素的多少, 与任务是否涉及心理理论功能是影响个体脑间活动同步现象的重要条件。未来研究可结合进化博弈论等理论模型, 进一步探索合作与协作行为的差异及规范形成的心理与神经机制。     

Infinitary Action Logic: Complexity, Models and Grammars

Action logic of Pratt [21] can be presented as Full Lambek Calculus FL [14, 17] enriched with Kleene star *; it is equivalent to the equational theory of residuated Kleene algebras (lattices). Some results on axiom systems, complexity and models of this logic were obtained in [4, 3, 18]. Here we prove a stronger form of *-elimination for the logic of *-continuous action lattices and the –completeness of the equational theories of action lattices of subsets of a finite monoid and action lattices of binary relations on a finite universe. We also discuss possible applications in linguistics. Presented by Jacek Malinowski     

Emergence of Information Transfer by Inductive Learning

We study a simple game theoretic model of information transfer which we consider to be a baseline model for capturing strategic aspects of epistemological questions. In particular, we focus on the question whether simple learning rules lead to an efficient transfer of information. We find that reinforcement learning, which is based exclusively on payoff experiences, is inadequate to generate efficient networks of information transfer. Fictitious play, the game theoretic counterpart to Carnapian inductive logic and a more sophisticated kind of learning, suffices to produce efficiency in information transfer.     

Constructive Logic with Strong Negation is a Substructural Logic. II

The goal of this two-part series of papers is to show that constructive logic with strong negation N is definitionally equivalent to a certain axiomatic extension NFL _ew of the substructural logic FL _ew . The main result of Part I of this series [41] shows that the equivalent variety semantics of N (namely, the variety of Nelson algebras) and the equivalent variety semantics of NFL _ew (namely, a certain variety of FL _ew -algebras) are term equivalent. In this paper, the term equivalence result of Part I [41] is lifted to the setting of deductive systems to establish the definitional equivalence of the logics N and NFL _ew . It follows from the definitional equivalence of these systems that constructive logic with strong negation is a substructural logic. Presented by Heinrich Wansing     

Interpolation in computing science: the semantics of modularization

The Interpolation Theorem, first formulated and proved by W. Craig fifty years ago for predicate logic, has been extended to many other logical frameworks and is being applied in several areas of computer science. We give a short overview, and focus on the theory of software systems and modules. An algebra of theories TA is presented, with a nonstandard interpretation of the existential quantifier . In TA, the interpolation property of the underlying logic corresponds with the quantifier combination property . It is shown how the Modularization Theorem, the Factorization Lemma and the Normal Form Theorem for module expressions can be proved in TA. Dedicated to the 50th anniversary of William Craig’s Interpolation Theorem.     

爱荷华博弈任务(IGT)与决策的认知神经机制

爱荷华博弈任务(IGT)是一项检查情感性决策机制的常用实验范式。据此, Damasio等人提出了躯体标记假设(SMH)解释情绪影响决策的神经生理机制。近期, 大量研究在IGT究竟是模糊决策还是风险决策、与情绪和认知的关系、与工作记忆和陈述性记忆的关系以及IGT的神经网络与分子遗传机制等方面积累了丰富资料。结果显示, IGT加工的早期由模糊决策主导, 情绪性躯体信号对引导决策选项的偏好可能起关键作用, 后期则倾向是一种风险决策, 认知评价和预期对选项偏向逐渐占优势; IGT与工作记忆的加工成分有相互重叠, 也需陈述性记忆的参与; IGT的加工不仅依赖于杏仁核、腹内侧前额皮层、眶额皮层等组成的情绪脑网络的活动, 还与背外侧前额皮层、海马、腹侧纹状体、岛叶皮层、辅助运动前区、扣带回皮层等许多脑区的活动有关; COMT和5-HTT的基因多态性会调节IGT相关的决策加工。总之, IGT是一项需要多重神经系统协同活动的决策加工任务, 且模糊与风险决策可能具有不同的遗传基础。     

Simulating Turing machines on Maurer machines

In a previous paper, we used Maurer machines to model and analyse micro-architectures. In the current paper, we investigate the connections between Turing machines and Maurer machines with the purpose to gain an insight into computability issues relating to Maurer machines. We introduce ways to simulate Turing machines on a Maurer machine which, dissenting from the classical theory of computability, take into account that in reality computations always take place on finite machines. In one of those ways, multi-threads and thread forking have an interesting theoretical application.