Strategic Market Games with a Finite Horizon and Incomplete.

We study a strategic market game associated to an intertemporal economy with a finite horizon and incomplete markets. We demonstrate that generically, for any finite number of players, every sequentially strictly individually rational and default-free stream of allocations can be approximated by a full subgame-perfect equilibrium. As a consequence, imperfect competition may Pareto-dominate perfect competition when markets are incomplete. Moreover — and this contrasts with the main message conveyed by the market games literature — there exists a large open set of initial endowments for which full subgame-perfect equilibria do not converge to η- efficient allocations when the number of players tends to infinity. Finally, strategic speculative bubbles may survive at full subgame-perfect equilibria.Market Games, Folk Theorem, Incomplete Markets, Bubbles.

Uptake of three doses of HPV vaccine by primary school girls in Eldoret, Kenya : a prospective cohort study in a malaria endemic setting

Background: All women are potentially at risk of developing cervical cancer at some point in their life, yet it is avoidable cause of death among women in Sub- Saharan Africa with a world incidence of 530,000 every year. It is the 4th commonest cancer affecting women worldwide with over 260,000 deaths reported in 2012. Low resource settings account for over 75% of the global cervical cancer burden. Uptake of HPV vaccination is limited in the developing world. WHO recommended that 2 doses of HPV vaccine could be given to young girls, based on studies in developed countries. However in Africa high rates of infections like malaria and worms can affect immune responses to vaccines, therefore three doses may still be necessary. The aim of this study was to identify barriers and facilitators associated with uptake of HPV vaccine. Methods: A cross-sectional survey was conducted at Eldoret, Kenya involving 3000 girls aged 9 to 14 years from 40 schools. Parents/guardians gave consent through a questionnaire. Results: Of all 3083 the school girls 93.8% had received childhood vaccines and 63.8% had a second HPV dose, and 39. 1% had a third dose. Administration of second dose and HPV knowledge were both strong predictors of completion of the third dose. Distance to the hospital was a statistically significant risk factor for non-completion (P: 0.01). Conclusions: Distance to vaccination centers requires a more innovative vaccine-delivery strategy and education of parents/guardians on cervical screening to increase attainment of the HPV vaccination

Uncertainty and Insurance in Strategic Market Games

In perfectly competitive economies under uncertainty, there is a well-known equivalence between a formulation with contingent goods and a formulation with state- specific securities followed by spot markets for goods. In this paper, I examine whether this equivalence carries over in a particular context of imperfect competition, strategic market games the Shapley-Shubik way. In that context, I look at hree games. One with contingent commodities, one with Arrow securities traded under imperfect competition and one with Arrow securities traded under perfect competition. First I show that these three games are (almost) payoff-equivalent. Then I compare their equilibrium sets. The first result is that if the securities markets follow the same imperfectly competitive rules of price formation as the goods markets, then the only common equilibria between the contingent markets formulation and the securities formulation are those which involve no transfer of income across states. This result was already obtained by Peck and Shell. The second result is that if the securities markets are competitive and all open, then the set of equilibria of the contingent markets formulation and the securities formulation coincide.

Three results on communication, information and common knowledge

I extend the results on communication, information and common knowledge by proving the following : 1. If n individuals with partitional information structures communicate their posterior probabilities of an event sequentially, one to one at a time, according to a scheme whim never excludes anyone permanently, and they revise in a nonmyopic way, then they eventually reach common knowledge. 2. If n individuals with partitional information structures form posterior probabilities of a given event and the minimum of their posteriors is common knowledge as well as the number of times it is attained then all posteriors must be equal. 3. Balancedness, the property of non-partitional information structures necessary and sufficient to prevent "Agreeing to Disagree", is in fact a very unrestrictive requirement. A new property, subnestedness, implies balancedness.

Uncertainty and insurance in strategic market games

For perfectly competitive economies under uncertainty, there is a well-known equivalence between a formulation with contingent goods and one with state-specific securities followed by spot markets for goods. In this paper, I examine whether this equivalence carries over to a particular form of imperfect competition. Specifically, I look at three Shapley-Shubik strategic market games: one with contingent commodities, one with Arrow securities traded under imperfect competition and one with Arrow securities traded under perfect competition. First I compare the feasibility constraints of these three games. Then I compare their equilibrium sets. As in Peck and Shell (1989), the only common equilibria between the first and the second game are those which involve no transfer of income across states. However, if the securities markets are competitive, then the set of equilibria of the contingent commodities game and the securities game coincide.Strategic markets games · Organization of markets under uncertainty.

Strategic market games with a finite horizon and incomplete markets

We study a strategic market game associated to an intertemporal economy with a finite horizon and incomplete markets. We demonstrate that generically, for any finite number of players, every sequentially strictly individually rational and default-free stream of allocations can be approximated by a full subgame-perfect equilibrium. As a consequence, imperfect competition may Pareto-dominate perfect competition when markets are incomplete. Moreover - and this contrasts with the main message conveyed by the market games literature - there exists a large open set of initial endowments for which full subgame-perfect equilibria do not converge to $\eta$ -efficient allocations when the number of players tends to infinity. Finally, strategic speculative bubbles may survive at full subgame-perfect equilibria. Copyright Springer-Verlag Berlin/Heidelberg 2004Strategic market games, Folk theorem, Incomplete markets, Bubbles.,

Convergence to competitive equilibria in a double auction

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