Learning to cooperate with Pavlov an adaptive strategy for the iterated Prisoner's Dilemma with noise

Conflict of interest may be modeled, heuristically, by the iterated Prisoner's Dilemma game. Although several researchers have shown that the Tit-For-Tat strategy can encourage the evolution of cooperation, this strategy can never outscore any opponent and it does poorly against its clone in a noisy environment. Here we examine the family of Pavlovian strategies which adapts its play by positive and negative conditioning, much as many animals do. Mutual cooperation will evolve in a contest with Pavlov against a wide variety of opponents and in particular against its clone. And the strategy is quite stable in a noisy environment. Although this strategy cooperates and retaliates, as does Tit-For-Tat, it is not forgiving; Pavlov will exploit altruistic strategies until he is punished by mutual defection. Moreover, Pavlovian strategies are natural models for many real life conflict-of-interest encounters as well as human and computer simulations.     

Institutions matter! Why the Herder Problem is not a Prisoner’s Dilemma

In the game theory literature, Garrett Hardin’s famous allegory of the “tragedy of the commons” has been modeled as a variant of the Prisoner’s Dilemma, labeled the Herder Problem (or, sometimes, the Commons Dilemma). This brief paper argues that important differences in the institutional structures of the standard Prisoner’s Dilemma and Herder Problem render the two games different in kind. Specifically, institutional impediments to communication and cooperation that ensure a dominant strategy of defection in the classic Prisoner’s Dilemma are absent in the Herder Problem. Their absence does not ensure that players will achieve a welfare-enhancing, cooperative solution to the Herders Problem, but does create far more opportunity for players to alter the expected payoffs through cooperative arrangements. In a properly modeled Herder Problem—along the lines of an assurance game—defection would not always be the dominant strategy. Consequently, the Herder Problem is not in the nature of a Prisoner’s Dilemma.     

Perceptron versus automaton in the finitely repeated prisoner’s dilemma

We study the finitely repeated prisoner’s dilemma in which the players are restricted to choosing strategies which are implementable by a machine with a bound on its complexity. One player has to use a finite automaton while the other player has to use a finite perceptron. Some examples illustrate that the sets of strategies which are induced by these two types of machines are different and not ordered by set inclusion. Repeated game payoffs are evaluated according to the limit of means. The main result establishes that a cooperation at almost all stages of the game is an equilibrium outcome if the complexity of the machines the players may use is limited enough and if the length T of the repeated game is sufficiently large. This result persists when more than T states are allowed in the player’s automaton. We further consider a variant of the model in which the two players are restricted to choosing strategies which are implementable by perceptrons and prove that the players can cooperate at most of the stages provided that the complexity of their perceptrons is sufficiently reduced.     

虚拟社区知识共享中的博弈问题分析

随着网络的普及,越来越多的人通过网络、通过虚拟社区来获取信息,但并不是所有的人都愿意无条件的将自己的知识贡献出来,让所有人得益。虚拟社区需要采取激励措施才能吸引、保留社区会员的加入和一直参与。     

The Emergence of Reactive Strategies in Simulated Heterogeneous Populations

The computer simulation study explores the impact of the duration of social impact on the generation and stabilization of cooperative strategies. Rather than seeding the simulations with a finite set of strategies, a continuous distribution of strategies is being defined. Members of heterogeneous populations were characterized by a pair of probabilistic reactive strategies: the probability to respond to cooperation by cooperation and the probability to respond to defection by cooperation. This generalized reactive strategy yields the standard TFT mechanism, the All-Cooperate, All-Defect and Bully strategies as special cases. Pairs of strategies interacted through a Prisoner's Dilemma game and exerted social influence on all other members. Manipulating: (i) the initial distribution of populations' strategies, and (ii) the duration of social influence, we monitored the conditions leading to the emergence and stabilization of cooperative strategies. Results show that: (1) The duration of interactions between pairs of strategies constitutes a crucial factor for the emergence and stabilization of cooperative strategies, (2) Unless sufficient learning intervals are provided, initializing the simulations with cooperative populations does not guarantee that cooperation will sustain.     

Varieties of marketisation in the UK: examining divergence in activation markets between Great Britain and Northern Ireland 2008–2014

This article examines the sub-national diversity in activation quasi-markets in the United Kingdom (UK). Through comparison of four active labour market programmes in Great Britain and Northern Ireland between 2008 and 2014, the article clarifies and maps intra-UK diversity in employment service governance and unpacks the shifting configurations of market structures in each jurisdiction to reveal a temporally and spatially distinct patterning of marketisation. Drawing on Gingrich's approach to analysis and classification of quasi-market variation, the article proposes that between 2008 and 2014, Great Britain rapidly evolved a provider-directed activation market. In contrast, the activation market structure in Northern Ireland, up to late 2014, is better characterised as state directed. A recent reconfiguration of the activation market in Northern Ireland does however indicate some (modified) convergence on Great Britain's approach. One common and consistent feature of the configuration of activation markets in each jurisdiction is the few powers given to direct users of employment services to shape contracted out provision.     

THE IMPORTANCE OF PROCEDURAL JUSTICE IN SECURING COMPLIANCE: A STUDY OF TAX SCHEME INVESTORS

Throughout the 1990s, tens of thousands of Australian taxpayers invested in mass‐marketed tax effective schemes. They enjoyed generous tax breaks until the Australian Taxation Office (ATO) told them in 1998 that they abused the system. This study examines the circumstances surrounding taxpayers' decision to invest in scheme arrangements. It also explores investors' perceptions of the way the ATO handled the schemes issue and, perhaps more importantly, why such a large number of investors defied the ATO's demands that they pay back taxes. Data were taken from in‐depth interviews conducted with 29 scheme investors. Consistent with the procedural justice literature, the findings revealed that many scheme investors defied the ATO's demands because the procedures the ATO used to handle the situation were perceived to be unfair. Given these findings, it will be argued that to effectively shape desired behaviour, regulators will need to move beyond enforcement strategies linked purely to deterrence. A strategy that aims to emphasise the procedural justice aspects of a regulatory encounter will be discussed.     

A test of the gambler's fallacy: Evidence from pari-mutuel games

The “gambler's fallacy” is the belief that the probability of an event is decreased when the event has occurred recently, even though the probability is objectively known to be independent across trials. Clotfelter and Cook (1991, 1993) find evidence of the gambler's fallacy in analysis of data from the Maryland lottery's“Pick 3” numbers game. In the Maryland lottery, the payout to all numbers is equal at $250 on a winning fifty-cent bet, so the gambler's fallacy betting strategy costs bettors nothing. This article looks at the importance of the gambler's fallacy in the New Jersey lottery's three-digit numbers game, a pari-mutuel game where a lower amount of total wagering on a number increases the payout to that number. Results indicate that the gambler's fallacy exists among bettors in New Jersey, although to a lesser extent than among those in Maryland.     

Financing urban growth in China: A case study of Guangzhou

Rapid urban growth has become a global phenomenon. As these city populations expand, urban governance is even more of a daunting challenge in many countries. China is not an exception. It is at once a transitional state still undergoing urbanization and economic development; it is also currently experiencing a slowing economy. China's cities must simultaneously continue to improve the quality of urban life while maintaining social stability. Using the city of Guangzhou as an example of China's mega-cities, this study explores the financing strategies used by Chinese cities to manage urban growth. While economic growth has always been the main priority, Guangzhou's strategy has not followed China's traditional approach of growth for growth's sake; instead, it is relying on investment in innovation and transportation to promote the local economy. Education is also being stressed as a means of fostering human resources. However, undisciplined infrastructure financing and ineffective intergovernmental fiscal relations are jeopardizing the city's fiscal sustainability. To correct this will require further reforms of China's fiscal system and a careful sequencing of reforms to maintain a sustainable growth in the urban area.     

Connecting with Sara: Facilitating attachment

This paper investigates the value and meaning of the attachment that forms within the therapeutic relationship. It follows the progress of a now 53‐month‐old African American homeless child as she is given the opportunity to form a human attachment through the use of Attachment and Object Relations theories. This paper integrates the work of developmental, attachment, and object relations theorists such as Mahler, Stern, Bowlby, Greenspan, Winnicott, and Fonegy. The child's story is illustrated through the use of documented history as told by the mother to the therapist and through clinical material from the child's therapeutic sessions.

This paper also examines what it means to be a culturally competent and responsible social worker. Research into parenting practices, beliefs, and skills among homeless, African American single women is discussed and integrated into a theory of practice.     

Effective choice in the single-shot Prisoner's Dilemma tournament

This paper discusses the results of a single-shot Prisoner's Dilemma computer tournament. In the single-shot Prisoner's Dilemma tournament each pair of players interacts only once. But players can establish and detect reputations because they know how their current opponent has behaved in previous games with other players. The results show that cooperation is worthwhile, even in single-shot games, provided the outcomes of previous games are common knowledge.Reality is a game, but you shouldn't take a game for reality(Pragmaticist Proverb)     

Perceptions of power and the management of environmental conflict: Forest politics in British Columbia

Political actors' perceptions of the contexts in which they act influence their strategies and behavior. A key element of political contexts is the configuration of power with respect to a conflict. We interviewed 28 individuals involved in British Columbia forest politics to determine their perceptions of the configuration of power, the nature of their political behavior, their dispositions with respect to institutionalized conflict resolution processes, and their policy goals. Our analysis generated two sets of conclusions. First, the B.C. government's efforts to address forest conflict will be hindered by the inconsistency between the conflict management strategy they have chosen and the mental models of politics held by key political actors. Second, the subjective realities of political actors can be used to explain variation in political behavior.     

The geography of fertility reduction in Kenya

Record high fertility levels were recorded for Kenya in the late 1970's; however, a fertility reversal was experienced during the 1980's. Recent studies by Njoru, Robinson and the National Research Council and data from the 1989 and 1993 KDHS indicate that the fertility decline is real and pervasive. The release of the 1989 census data provides researchers with an additional source to document the fertility decline and to identify the spatial pattern of fertility reduction at the province and district level. The geography of fertility reduction is explored by addressing differences in the annual rate of population growth for each province and district.     

Combating Conflicting Messages of Values: A Closer Look at Parental Strategies

This study examined how parents respond when their children encounter values outside the home that conflict with family values. Forty‐eight middle‐class European American parents completed questionnaires consisting of 11 vignettes asking how they would respond to hypothetical situations where outside sources posed potential conflicts with parental values to their adolescent child (M age of child=13.33 years). We identified five strategies that parents might use: controlled cocooning, reasoned cocooning, compromise, pre‐arming, and deference. Parents in the study enlisted all five strategies, with reasoned cocooning and pre‐arming occurring most frequently. The self‐reported importance of values to parents was the most important predictor of which strategy parents used, with parents using more controlling strategies to defend values that were most important to them. Importance of values also mediated the relation between religion and the parent's self‐reported desire for the child's compliance on personal issues, and parental strategy choice. This study is among the first to examine alternative parental strategies for regulating children's values acquisition outside the home, and shows that the extent of parental control is related to the importance of specific values to the parent.     

中国发展南太平洋地区关系的外交战略

南太平洋地处中国外交大周边,构建良好的南太平洋周边环境是中国外交战略的重要组成部分。考虑到南太平洋地区独特的外交环境以及中国与南太平洋国家关系的现状,中国应坚持将南太平洋地区作为"经济伙伴"、"政治依托"和"安全保障"的战略定位,抓住双方的共同需求和合作愿望,通过多种途径推进双方关系的发展。尽管中国与南太平洋国家关系的发展受到一些内外因素的影响,但随着经济和社会的进一步发展,双方在各自对外战略中的地位将会继续得到提升,从而为双方关系持续、稳定、深入发展创造更为广阔的空间。     

Teenagers' Multisensory Routes for Learning in the Museum

ABSTRACT

In this article I draw on a study of sensory aspects of teenagers' use of digital media, how these sensory aspects are incorporated in emerging learning strategies, and the implications of this for the same teenagers' engagement in museums. My focus is on how an ethnographic approach that attends to the senses may enable a critical review of prevailing pedagogical ideas in museums. Recent developments in museum education have led to large investments in state-of-the-art technology to produce interactive, multisensory exhibits. However, the question of how teenagers respond to these campaigns remains rather under-researched. This article shows how habitual use of digital media in teenage everyday practice incorporates learning to appropriate other people's experiences and ideas through a configuration of vision, touch, motion, and imagination, thereby enhancing non-representational learning qualities such as affect and sensation. The implications of this sensory approach open up routes to differentiate pedagogical settings in museums that on a superficial level apply the same educational technologies, but since they are based in different sensorial belief systems, different conditions for learning unfold in their use. In developing this analysis I argue that through ethnographic attention to the senses we might advance theories of learning within museum education.     

“Altered Observation of Modern Eyes”: Mina Loy's Collages,and Multisensual Aesthetics

ABSTRACT

This article traces the emergence of a multisensual aesthetic in the works of modernist avant-garde artist and poet Mina Loy. Loy's creative efforts were heterogeneous, spanning multiple media: a poet and painter, she was also a designer, actor and inventor. Seeking to instantiate herself in a cultural climate which tended to objectify the female body, Loy's multisensual art aimed to make the viewer/listener/reader sense as she did, and, in so doing, made important advances in the cultural configuration of women as whole, complex beings worthy of intellectual, physical, artistic and spiritual presence in the world.

Loy's assemblage art of the 1950s is shown to be a radical attempt to push the medium of collage into a more complex dimensionality in an effort to represent emerging understandings of perception and consciousness, positioning her as a major contributor to a defining art form of modernism. Bolstered by an appreciation of her own body as sensually charged and relational, Loy ascertained the simultaneity of present absence, connectivity and juxtaposition characterizing collage. This article articulates how, by troubling normative conceptions of dimensionality Loy's assemblages underscore the material and textual aspects of language explored in her collage-inflected poetry.     

Strategies for the Study of Individual Development within Naturally-Existing Peer Groups*

The investigation of peer influences on children's development in natural settings rests squarely on appropriate methods to identify those individuals who are influential for a given child. Traditional methods of sociometric ratings or assessments of friendship choices are not intended to identify reciprocal influences in children's peer groups of social interrelationships. In the study of networks within sociology, researchers have focused on the structural properties of children's networks, instead of the psychologically meaningful characteristics of the children who comprise a target child's network. To complement these strategies, a method is presented that can reliably identify those individuals who constitute children's natural peer groups in a setting. This information is used to form composite maps that represent the psychological peer context of a given child. Strategies are outlined for analyzing processes of group selection and socialization among developing individuals and their changing peer contexts.     

Methodological and Validity Issues Involved in the Collection of Sensitive Information From Children in Foster Care

ABSTRACT

The Illinois Child Well-Being Study (ICWBS) established a red-flag reporting system (RFRS) embedded in the Audio Computer Assisted Self Interview (ACASI) portion of its child survey to flag reports of violence toward the child, suicidality, neglect, and/or sexual exploitation. When those RFRS questions were positively answered, the reported incident was relayed to the child's caseworker and investigated. This study describes the RFRS, the analysis of the children's reports, and a content analysis of the caseworkers' investigation. In this study, 166 children were interviewed and 28 children reported 36 RFRS incidents. On investigation, only 6 RFRS incidents were verified; most RFRS incidents were reported in error. The results of this study may help researchers using similar RFRS protocols.     

Differences between resource control types revisited: A short term longitudinal study

Hawley's influential resource control theory (RCT) posits that both coercive and prosocial strategies may yield social dominance, as indexed by resource control. Based on differences in youths’ relative use of these strategies, RCT a priori defines five distinct subtypes. Several studies by Hawley and colleagues have revealed substantial differences between subtypes in terms of obtained resource control and various social characteristics (e.g., agreeableness). The present longitudinal study (N = 394; M _age = 10.3; SD = 0.5) expands on previous work. Firstly, because several items used to assess strategies in RCT appear to confound strategy use with the resulting benefits (resource control), we disentangled between strategy use as such and obtained resource control. Secondly whereas previous work has been exclusively cross‐sectional, the present study was longitudinal. ANOVAs comparing subgroups provided support for some core tenets of RCT, but not for others. For instance, bistrategic children scored high on both resource control and perceived popularity. However, bistrategics engaged in elevated bullying, and whereas Hawley asserts that they are proficient in balancing ‘getting ahead’ with ‘getting along’, their behavior appeared to evoke clear negative reactions in the peer group at large. Findings also showed that non‐controllers did not experience more negative outcomes than their peers across all domains.