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An important aspect of network dynamics that has been missing from our understanding of network dynamics in various applied settings is the influence of strategic behavior in determining equilibrium network dynamics. Our main objective hears to say what we can regarding the emergence of stable club networks—and therefore, stable coalition structures—based on the stability properties of strategically determined equilibrium network formation dynamics. Because club networks are layered networks, our work here can be thought of as a first work on the strategic dynamics of layered networks. In addition to constructing a discounted stochastic game model (i.e., a DSG model) of club network formation, (1) we show that our DSG of network formation possesses a stationary Markov perfect equilibrium in players' membership-action strategies; (2) we identify the assumptions on primitives which ensure that the induced equilibrium Markov process of layered club network formation satisfies the Tweedie Stability Conditions (Tweedie in Stoch Processes Their Appl 92:345–354) and (3) we show that, as a consequence, the equilibrium Markov network formation process generates a unique decomposition of the set of state-network pairs into a transient set together with finitely many basins of attraction. Moreover, we show that if there is a basin containing a vio set (a visited infinitely often set) of club networks sufficiently close together, then the coalition structures across club networks in the vio set will be the same (i.e., closeness across networks in a vio set leads to invariance in coalition structure across networks in a vio set). [ABSTRACT FROM AUTHOR]

An important aspect of network dynamics that has been missing from our understanding of network dynamics in various applied settings is the influence of strategic behavior in determining equilibrium network dynamics. Our main objective hear to say what we can regarding the emergence of stable club networks—and therefore, stable coalition structures—based on the stability properties of strategically determined equilibrium network formation dynamics. Because club networks are layered networks, our work here can be thought of as a first work on the strategic dynamics of layered networks. In addition to constructing a discounted stochastic game model (i.e., a DSG model) of club network formation, (1) we show that our DSG of network formation possesses a stationary Markov perfect equilibrium in players' membership-action strategies; (2) we identify the assumptions on primitives which ensure that the induced equilibrium Markov process of layered club network formation satisfies the Tweedie Stability Conditions (Tweedie in Stoch Process Appl 92:345–354, 2001) and (3) we show that, as a consequence, the equilibrium Markov network formation process generates a unique decomposition of the set of state-network pairs into a transient set together with finitely many basins of attraction. Moreover, we show that if there is a basin containing a vio set (a visited infinitely often set) of club networks sufficiently close together, then the coalition structures across club networks in the vio set will be the same (i.e., closeness across networks in a vio set leads to invariance in coalition structure across networks in a vio set). [ABSTRACT FROM AUTHOR]

We show that any measurable selection valued correspondence induced by the composition of an m-tuple of real-valued Caratheodory functions with an upper Caratheodory (uC) correspondence has fixed points if the underlying uC correspondence in the composition contains a continuum valued uC sub-correspondence. As an application, we show that all uncountable-compact discounted stochastic games ( DSG s ) satisfying the usual assumptions have Nash payoff selection correspondences having fixed points provided of course that the uC Nash correspondence contains a continuum valued uC Nash sub-correspondence. Fu and Page [8] have shown that all such DSG s , in fact, have uC Nash correspondences containing continuum valued uC Nash sub-correspondences—implying, therefore, that all DSG s satisfying the usual assumptions have stationary Markov perfect equilibria. [ABSTRACT FROM AUTHOR]

Agent-based modelling can be used to investigate the behavioural and social aspects of tax compliance. We illustrate the approach with two models. The first model emphasises the role of occupational choice in tax compliance, and explores the effect of non-compliance on risk-taking and income distribution. The modelling of the compliance decision is discussed with an emphasis on decision-making under uncertainty and social interaction. We then add to the model a social network which governs the transmission of information on attitudes and beliefs, and investigate alternative audit strategies. A strategy of auditing a fixed number of taxpayers from each occupation dominates alternative strategies (including random and focussed strategies) in the sense of first-order stochastic dominance. [ABSTRACT FROM AUTHOR]

Using a dynamic network formation model, solved numerically, we study banks' rollover decisions. We find that when the existence of linkages between market participants generates an informational externality, the newly formed network is conditioned by past architectures. Moreover, this inertia is strongly dependent on macroeconomic conditions, such as investors' risk appetite. Simulations show that for intermediate values of the risk appetite's parameter the financial network exhibits tipping points, i.e., the inability to maintain a threshold number of linkages may push the market into a gridlock. In this context, we study also how policy instruments, such as taxes and subsidies, affects debt rollover. Since a reduction in the policy level plays the same role as an improvement in economic fundamentals, the creation of interbank connections can be stimulated by it. Thus, in order to restart lending after a major stress situation in the interbank market a considerable reduction in the policy level is required, advising a counter-cyclical policy similar to the ones recently proposed with respect to capital requirements. [ABSTRACT FROM AUTHOR]

Painted apple moth Teia anartoides Walker (Lepidoptera: Lymantriidae), a native to Australia, was discovered in Auckland, New Zealand in late 1999 and eradicated by 2006. It was recognised in 2002 that biological control would be the most effective long-term control strategy if eradication was unsuccessful, and a search was initiated for potential biocontrol agents in Australia. In 2003, autumn and spring surveys were undertaken in Victoria, Tasmania and South Australia of the guild of parasitoid natural enemies of T. anartoides. Eggs, larvae and pupae were collected and held to rear out any parasitoids. In addition, localised searches were made in Queensland in late 2003-early 2004 and laboratory-reared juvenile stages of T. anartoides were released for recapture in both Victoria and Queensland. Acacia dealbata Link (Fabales: Fabaceae) was the main plant from which T. anartoides was recovered, followed by apple. Most T. anartoides samples were collected from Victoria and Tasmania. Eighteen species from 13 genera of egg, larval and pupal parasitoids were reared and included Diptera (Tachinidae) and Hymenoptera (Braconidae, Encyrtidae, Eulophidae and Ichneumonidae). Of the seven Hymenopteran genera recovered from the larval stage, the most common in Victoria and Tasmania was a previously unidentified larval parasitoid Cotesia Cameron (Hymenoptera: Braconidae) sp. Echthromorpha intricatoria (Fabricius) (Hymenoptera: Ichneumonidae) was the dominant pupal parasitoid. The survey showed that the parasitoid complex associated with T. anartoides is structurally very similar to that on other pest Lymantriidae in the northern hemisphere such as gypsy moth ( Lymantria dispar L.) (Lepidoptera: Lymantriidae). Meteorus pulchricornis (Wesmael) (Hymenoptera: Braconidae) was recorded for the first time in Australia. [ABSTRACT FROM AUTHOR]

We model strategic competition in a market with asymmetric information as a noncooperative game in which each seller competes for a buyer of unknown type by offering the buyer a catalog of products and prices. We call this game a catalog game. Our main objective is to show that catalog games have Nash equilibria. The Nash existence problem for catalog games is particularly contentious due to payoff discontinuities caused by tie-breaking. We make three contributions. First, we establish under very mild conditions on primitives that no matter what the tie-breaking rule, catalog games are uniformly payoff secure, and therefore have mixed extensions which are payoff secure. Second, we show that if the tie-breaking rule awards the sale to firms which value it most (i.e., breaks ties in favor of firms which stand to make the highest profit), then firm profits are reciprocally upper semicontinuous (i.e., the mixed catalog game is reciprocally upper semincontinuous). This in turn implies that the mixed catalog game satisfies Reny’s condition of better-reply security—a condition sufficient for existence (Reny in Econometrica 67:1029–1056, 1999). Third, we show by example that if the tie-breaking rule does not award the sale to firms which value it most (for example, if ties are broken randomly with equal probability), then the catalog game has no Nash equilibrium. [ABSTRACT FROM AUTHOR]

We introduce a no-risky-arbitrage price condition (NRAP) for asset market models allowing both unbounded short sales and externalities such as trading volume. We then demonstrate that NRAP is sufficient for the existence of competitive equilibrium in the presence of externalities. Moreover, we show that if all risky arbitrages are utility increasing, then NRAP characterizes competitive equilibrium in the presence of externalities. [ABSTRACT FROM AUTHOR]

We introduce consumption externalities into a general equilibrium model with arbitrary consumption sets. To treat the problem of existence of equilibrium, a condition of no unbounded arbitrage, extending the condition of Page (1987) and Page and Wooders (1993, 1996) is defined. It is proven that this condition is sufficient for the existence of an equilibrium and both necessary and sufficient for compactness of the set of rational allocations. [ABSTRACT FROM AUTHOR]

Within the class dominant strategy incentive compatible mechanisms, we show that there exists an optimal contracting mechanism for the principal for a version of the incomplete information principal-agent problem in which several agents compete for a contract and the principal selects an agent via a contract auction. In our auction model, we assume that the principal and the agents are risk averse, and we allow for uncountably many agent types. We also assume that the principal's probability measure over type profiles in such that correlation between agent's types is possible. Thus, we do not require that agents' types be independently distributed. Finally, we impose limited liability constraints upon the set of contracts. Due to the nature of the individual rationality and incentive compatibility constraints, the existence problem is nonstandard and novel existence arguments are required. We prove existence using a measurable selection result and a new notion of compactness called K-compactness. [ABSTRACT FROM AUTHOR]

We study the problem faced by an incomplete information monopolist seeking to design a line of contracts so as to simultaneously screen consumers by type and resolve the moral hazard problems associated with contract performance. We formulate the monopolist's problem as a mechanism design problem in which the set of consumer types is taken to be a Polish space, and the contract space an arbitrary compact metric space. Allowing for risk aversion on the part of the monopolist and consumers, and taking as the feasible set of mechanisms the collection of all measurable functions defined on the space of consumer types with values in the space of contracts, we present a new characterization of incentive compatibility in an infinite dimensional setting which allows us to reformulate the monopolist's design problem as an unconstrained optimization problem (i.e., as a problem without the incentive compatibility constraints). Using simple techniques, we then demonstrate the existence of an optimal screening mechanism for the monopolist. We thus extend the existing analysis of the incomplete information monopoly problem to an infinite dimensional setting with moral hazard, and we provide an existence result not available in the existing literature. [ABSTRACT FROM AUTHOR]

The section focuses on rules for practicing pupils in problem-solving. It outlines some of the significant points about the thinking processes that Professor John Dewey made in his book "How We Think." It cites the components of careful inquiry. It presents role that teachers play in enhancing the problem-solving skills of students.

Multi-stakeholder partnerships are an essential vehicle for solving complex societal problems. Agreements governing these partnerships often lack equitable partner agency in framing and enforcing multi-stakeholder agreements. This challenges the partner cooperation needed of partnerships to be effective. This theoretical paper introduces a new original model to measure and develop the cooperative capacity of multi-stakeholder partnerships so that future agreements involving the partnership are framed to share governance equitably among all partners and hence, increase partnership performance and effectiveness. The model provides a methodology to measure and develop the cooperative capacity of multi-stakeholder partnerships through key performance indicators that identify the cooperative state of partners and predicts partnership effectiveness in achieving common goals. The paper traces the theoretical genesis of the model, presents a comprehensive explanation of the model, and provides cases of the model's application. [ABSTRACT FROM AUTHOR]

We establish a fixed point theorem for the composition of nonconvex, measurable selection valued correspondences with Banach space valued selections. We show that if the underlying probability space of states is nonatomic and if the selection correspondences in the composition are K-correspondences (meaning correspondences having graphs that contain their Komlos limits), then the induced measurable selection valued composition correspondence takes contractible values and therefore has fixed points. As an application we use our fixed point result to show that all nonatomic uncountable-compact discounted stochastic games have stationary Markov perfect equilibria – thus resolving a long-standing open question in game theory. [ABSTRACT FROM AUTHOR]

The article cites a teaching method in which the outside world is brought inside the classroom through the messages of carefully chosen speakers. Lecturers talked in response to a specific need for further enlightenment on a definite subject. For example, geography classes had frequent talks from recent travelers. By doing so, three purposes were accomplished. These were the enlightenment of the pupils, enlightenment of the parents and the community and sale of the school to the public.

A letter to the editor is presented regarding the reader's request for an official bulletin board during the meeting of the National Education Association where in they could insert their plans for school trips.