Infinite games with finite knowledge gaps

Infinite games where several players seek to coordinate under imperfect information are deemed to be undecidable, unless the information is hierarchically ordered among the players. We identify a class of games for which joint winning strategies can be constructed effectively without restricting the direction of information flow. Instead, our condition requires that the players attain common knowledge about the actual state of the game over and over again along every play. We show that it is decidable whether a given game satisfies the condition, and prove tight complexity bounds for the strategy synthesis problem under $\omega$-regular winning conditions given by parity automata.Comment: 39 pages; 2nd revision; submitted to Information and Computatio

Does size really matter: a review of the role of stake and prize levels in relation to gambling-related harm

Regulatory and industry decisions influencing commercial gambling activities require clear understanding of the role that stakes and prizes play in the development and facilitation of gambling-related harm. Although industry proponents argue for increases in stakes and prizes to meet market demands, regulators remain cautious about the potential implication for gambling-related harm, while industry opponents generally condemn relaxing aspects of gambling policies. To inform this debate, this paper provides a critical examination of the relevant literature. From the review, it is concluded that limitations of the existing literature restrict our ability to draw definitive conclusions regarding the effects of stake and prize variables. Most studies contain multiple, methodological limitations, the most significant of which are diluted risk and reward scenarios used in analogue research settings not reflective of real gambling situations. In addition, there is a lack of conceptual clarity regarding many constructs, particularly the parameters defining jackpots, and the interactive nature and effect of the differing configurations of game parameters and environments are often not taken into consideration when investigating changes to one or more variables. Notwithstanding these limitations, there is sufficient evidence to suggest that stake and prize levels merit consideration in relation to harm minimisation efforts. However, substantial knowledge gaps currently exist, particularly in relation to understanding staking and prize thresholds for risky behaviour, how the impact of stakes and prizes change depending on the configuration and interaction of other game characteristics, and the role of individual and situational determinants. Based on the potential risk factors and the implications for commercial appeal, a player-focussed harm minimisation response may hold the most promise for future research and evaluation in jurisdictions where gambling is a legal and legitimate leisure activity

Distributed Graph Automata and Verification of Distributed Algorithms

Combining ideas from distributed algorithms and alternating automata, we introduce a new class of finite graph automata that recognize precisely the languages of finite graphs definable in monadic second-order logic. By restricting transitions to be nondeterministic or deterministic, we also obtain two strictly weaker variants of our automata for which the emptiness problem is decidable. As an application, we suggest how suitable graph automata might be useful in formal verification of distributed algorithms, using Floyd-Hoare logic.Comment: 26 pages, 6 figures, includes a condensed version of the author's Master's thesis arXiv:1404.6503. (This version of the article (v2) is identical to the previous one (v1), except for minor changes in phrasing.

Targets and indicators in World Bank population projects

In reviewing World Bank evaluations of the impact of population projects, the author explains the nature and uses of four families of performance indicators. Two measure inputs: Project implementation indicators, which are project-specific, are the principal measures used in Bank supervision. They measure success in creating sources capable of conducting certain desired activities. Process (or activity) indicators measure performance of a project's intended activities but tell nothing about the yield or output of those activities. Two measure output: Performance (or intermediate-output) indicators measure the yield or output-performance of a project or program. For family planning, the principal indicator in this category is acceptor figures, normally with details about methods used plus the age, parity, and geographical distribution of acceptors. Quality may or may not be good and coverage may or may not be comprehensive. These indicators do not directly measure ultimate demographic impacts - lower fertility and slower population growth. Demographic outcome (or impact) indicators do measure demographic impacts, usually the contraceptive prevalence rate and age-specific and total fertility rates. One can use a desired value of any comparator as a target, but a target is only one possible comparator. Two more widely used comparators for family planning are trends (comparing current with past performance) and international performance (an external comparison). The author recommends strengthening the Bank's use of world (successful developing country) standards and of trend analysis rather than increasing its use of target setting. The Bank's primary interest is normally the performance of the borrower's national program, so more attention should be given to program-level rather than to project-level performance - except for pilot projects. The author recommends: that the Bank standardize its terminology about these four families of indicators; that the Population and Human Resources Department periodically prepare comparator tables and graphs for use in Bank project and sector reports; that the Bank discontinue Project Performance Audit Reports on population projects, as they seldom add much to information and judgments contained in Project Completion Reports - the money saved could be applied to more effective evaluation research; that operational staff show more concern for a program's contraceptive mix; that more attention be paid to a program's service quality; and that the use of demographic and health surveys be the rule, not the exception, in Bank population and health projects.Poverty Monitoring&Analysis,Health Monitoring&Evaluation,Agricultural Research,Health Economics&Finance,Scientific Research&Science Parks

Multilateral negotiations with private side-deals: a multiplicity example

We study a multilateral negotiation procedure that allows for "partial agreements" in which responders are told only their own shares. Applications of our model include negotiations under "joint and several liability." Unlike previous models of multilateral bargaining with exit, we find that there are multiple equilibrium outcomes.imperfect information

Rating the Suitability of Responsible Gambling Features for Specific Game Types: A Resource for Optimizing Responsible Gambling Strategy

A Delphi based study, rated the perceived effectiveness of 45 responsible gambling (RG) features in relation to 20 distinct gambling type games. Participants were 61 raters from seven countries,including responsible gambling experts (n = 22), treatment providers (n = 19) and recovered problem gamblers (n = 20). The most highly recommended RG features could be divided into three groups 1) Player initiated tools focused on aiding player’s behaviour 2) RG features related to informed-player-choice 3) RG features focused on gaming company actions. Overall, player control over personal limits were favoured more than gaming company controlled limits, although mandatory use of such features was often recommended. The study found that recommended RG features varied considerably between game types, according to their structural characteristics. Also,online games had the possibility to provide many more RG features than traditional (offline games). The findings draw together knowledge about the effectiveness of RG features for specific game types. This should aid objective, cost-effective, evidence based decisions on which RG features toi nclude in an RG strategy, according to a specific portfolio of games. The findings of this study will be available via a web-based tool, known as the Responsible Gambling Knowledge Centre (RGKC)

On Dynamic Compromise

What prevents majorities from extracting surplus from minorities in a dynamic legislative process? In this paper we study an infinitely repeated game where legislators determine the division of a surplus each period. A division proposal is made at the beginning of the period by a randomly selected legislator and is then voted on. Proposals that are accepted by a simple majority are implemented, otherwise the status quo allocation prevails. We show existence of a symmetric Markov perfect equilibrium in which more than a minimum winning majority receive a positive allocation for an intermediate range of discount factors. However, the equilibrium outcome is sensitive to initial conditions: compromise is achieved when initial allocations are well distributed, otherwise the equilibrium spirals towards a complete absence of compromise. We find that, contrary to intuition, compromise becomes easier to sustain as the number of legislators increases. Classification-JEL Codes: C73, D74