Flexible information acquisition and optimal Tobin tax in tractable dynamic global games

My dissertation focuses on dynamic aspects of coordination processes such as reversibility of early actions, option to delay decisions, and learning of the environment from the observation of other people’s actions. This study proposes the use of tractable dynamic global games where players privately and passively learn about their actions’ true payoffs and are able to adjust early investment decisions to the arrival of new information to investigate the consequences of the presence of liquidity shocks to the performance of a Tobin tax as a policy intended to foster coordination success (chapter 1), and the adequacy of the use of a Tobin tax in order to reduce an economy’s vulnerability to sudden stops (chapter 2). Then, it analyzes players’ incentive to acquire costly information in a sequential decision setting (chapter 3). In chapter 1, a continuum of foreign agents decide whether to enter or not in an investment project. A fraction λ of them are hit by liquidity restrictions in a second period and are forced to withdraw early investment or precluded from investing in the interim period, depending on the actions they chose in the first period. Players not affected by the liquidity shock are able to revise early decisions. Coordination success is increasing in the aggregate investment and decreasing in the aggregate volume of capital exit. Without liquidity shocks, aggregate investment is (in a pivotal contingency) invariant to frictions like a tax on short term capitals. In this case, a Tobin tax always increases success incidence. In the presence of liquidity shocks, this invariance result no longer holds in equilibrium. A Tobin tax becomes harmful to aggregate investment, which may reduces success incidence if the economy does not benefit enough from avoiding capital reversals. It is shown that the Tobin tax that maximizes the ex-ante probability of successfully coordinated investment is decreasing in the liquidity shock. Chapter 2 studies the effects of a Tobin tax in the same setting of the global game model proposed in chapter 1, with the exception that the liquidity shock is considered stochastic, i.e, there is also aggregate uncertainty about the extension of the liquidity restrictions. It identifies conditions under which, in the unique equilibrium of the model with low probability of liquidity shocks but large dry-ups, a Tobin tax is welfare improving, helping agents to coordinate on the good outcome. The model provides a rationale for a Tobin tax on economies that are prone to sudden stops. The optimal Tobin tax tends to be larger when capital reversals are more harmful and when the fraction of agents hit by liquidity shocks is smaller. Chapter 3 focuses on information acquisition in a sequential decision game with payoff complementar- ity and information externality. When information is cheap relatively to players’ incentive to coordinate actions, only the first player chooses to process information; the second player learns about the true payoff distribution from the observation of the first player’s decision and follows her action. Miscoordination requires that both players privately precess information, which tends to happen when it is expensive and the prior knowledge about the distribution of the payoffs has a large variance.

Essays on coordination problems in economics

No estudo da economia, há diversas situações em que a propensão de um indivíduo a tomar determinada ação é crescente na quantidade de outras pessoas que este indivíduo acredita que tomarão a mesma ação. Esse tipo de complementaridade estratégica geralmente leva à existência de múltiplos equilíbrios. Além disso, o resultado atingido pelas decisões decentralizadas dos agentes pode ser ineficiente, deixando espaço para intervenções de política econômica. Esta tese estuda diferentes ambientes em que a coordenação entre indivíduos é importante. O primeiro capítulo analisa como a manipulação de informação e a divulgação de informação afetam a coordenação entre investidores e o bem-estar em um modelo de corridas bancárias. No modelo, há uma autoridade reguladora que não pode se comprometer a revelar a verdadeira situação do setor bancário. O regulador observa informações idiossincráticas dos bancos (através de um stress test, por exemplo) e escolhe se revela essa informação para o público ou se divulga somente um relatório agregado sobre a saúde do sistema financeiro como um todo. O relatório agregado pode ser distorcido a um custo – um custo mais elevado significa maior credibilidade do regulador. Os investidores estão cientes dos incentivos do regulador a esconder más notícias do mercado, mas a manipulação de informação pode, ainda assim, ser efetiva. Se a credibilidade do regulador não for muito baixa, a política de divulgação de informação é estado-contingente, e existe sempre um conjunto de estados em que há manipulação de informação em equilíbrio. Se a credibilidade for suficientemente baixa, porém, o regulador opta por transparência total dos resultados banco-específicos, caso em que somente os bancos mais sólidos sobrevivem. Uma política de opacidade levaria a uma crise bancária sistêmica, independentemente do estado. O nível de credibilidade que maximiza o bem-estar agregado do ponto de vista ex ante é interior. O segundo e o terceiro capítulos estudam problemas de coordenação dinâmicos. O segundo capítulo analisa o bem-estar em um ambiente em que agentes recebem oportunidades aleatórias para migrar entre duas redes. Os resultados mostram que sempre que a rede de pior qualidade (intrínseca) prevalece, isto é eficiente. Na verdade, um planejador central estaria ainda mais inclinado a escolher a rede de pior qualidade. Em equilíbrio, pode haver mudanças ineficientes que ampliem a rede de qualidade superior. Quando indivíduos escolhem entre dois padrões ou redes com níveis de qualidade diferentes, se todos os indivíduos fizessem escolhas simultâneas, a solução eficiente seria que todos adotassem a rede de melhor qualidade. No entanto, quando há fricções e os agentes tomam decisões escalonadas, a solução eficiente difere ix do senso comum. O terceiro capítulo analisa um problema de coordenação dinâmico com decisões escalonadas em que os agentes são heterogêneos ex ante. No modelo, existe um único equilíbrio, caracterizado por thresholds que determinam as escolhas para cada tipo de agente. Apesar da heterogeneidade nos payoffs, há bastante conformidade nas ações individuais em equilíbrio. Os thresholds de diferentes tipos de agentes coincidem parcialmente contanto que exista um conjunto de crenças arbitrário que justifique esta conformidade. No entanto, as estratégias de equilíbrio de diferentes tipos nunca coincidem totalmente. Além disso, a conformidade não é ineficiente. A solução eficiente apresentaria estratégias ainda mais similares para tipos distintos em comparação com o equilíbrio decentralizado.

Now everything looks like a game : Mobile phones and location-based games.

This paper explores how we may transform peoples’ perceived access to cultural participation by exploiting the possible relationships between place, play and mobile devices. It presents SCOOT; a location-based game in order to investigate how aspects of game-play can be employed to evoke at once playful and culturally meaningful experiences of place. In particular this paper is concerned with how the portable, communicative and social affordances of mobile phones are integral to making a “now everything looks like a game” experience.

Maintaining human agency in the design on context-aware systems : Design games in a dental surgery

This paper describes a series of design games, specifically aimed at exploring shifts in human agency in order to inform the design of context-aware applications. The games focused on understanding information handling issues in dental practice with participants from a university dental school playing an active role in the activities. Participatory design activities help participants to reveal potential implicit technical resources that can be presented explicitly in technologies in order to assist humans in managing their interactions with and amidst technical systems gracefully.

Co-creating games: A co-evolutionary analysis

ABSTRACT. The phenomenon of consumer co-creation is often framed in terms of whether either economic market forces or socio-cultural non-market forces ultimately dominate. We propose an alternate model of consumer co-creation in terms of co-evolution between markets and non-markets. Our model is based on a recent ethnographic study of a massively multiplayer online game through its development, release and ultimate failure, and cast in terms of two explanatory models: multiple games and social network markets. We conclude that consumer co-creation is indeed complex, but in ways that relate to both emergent market expectations and the evolution of markets, not to the transcendence of markets.

Co-creative expertise : Auran Games and Fury - a case study

This article discusses the ways in which the relations among professional and non-professional participants in co-creative relations are being reconfigured as part of the shift from a closed industrial paradigm of expertise toward open and distributed expertise networks. This article draws on ethnographic consultancy research undertaken throughout 2007 with Auran Games, a Brisbane, Australia based games developer, to explore the co-creative relationships between professional developers and gamers. This research followed and informed Auran’s online community management and social networking strategies for Fury (http://unleashthefury.com), a massively multiplayer online game released in October 2007. This paper argues that these co-creative forms of expertise involve co-ordinating expertises through social-network markets.

Empowerment games : empathic design probes for user participation in community housing

This paper documents the empowering process of a group of public housing residents through different design probing exercises. These exercises worked along with existing social processes without any involvement of designers. This paper shows how a design researcher devised a series of probing tools called "empowerment games" with a group of active users. These games are self-learning tools for making the abstract language of design legible to users. The main purpose of this intitiative was to change the preconception of govenmental bodies and professional designers of the passivity of the users with regard to their designed environment. This was the first case of the application of a participatory design process in Hong Kong subsidized housing. Design empathy is a central skill when working with users throughout the whole design research project.

Brand placements in computer and video games : an overview and research questions

Despite the size and growth of the computer and video gaming industry – as well as the increasing use of the medium for the placement of advertising and product placement – researchers have neglected this area. By drawing on existing literature and research in similar and related areas of film product placement, sponsorship and interactivity, the authors present a conceptual overview and identify areas for research.

A review of the video games industry in the United States

With increasing revenues for video game manufacturers, higher software sales and a more diverse audience, the video games industry has been experiencing strong and rapid growth in recent times, rivalling other forms of entertainment. As a result, games have begun to attract the attention of marketing practitioners who are finding it increasingly difficult to attract consumer attention, and are seeking alternative media for marketing communications. This paper provides a review of the video games industry in the United States and raises the question as to whether games are a viable new medium for marketing messages. Areas for research are identified.

Exploring product placement in video games : an investigation of recall effects

Despite its growth and prominence, product placement is generally under-researched and this is even more apparent in the area of placement in video gaming. This paper presents exploratory focus group research into this practice. Findings indicate that the introductory footage to a game provides placement opportunities with the highest level of recall, while peripheral non-action is the worst. Interestingly, recall also appears to be higher for individual brands as opposed to manufacturer brands.

Sodium 2-nitrocinnamate dihydrate: a one-dimensional hydrogen-bonded coordination polymer

The title compound catena-poly[aqua-mu3-2-nitrocinnamato], [Na(C9H6NO4)(H2O)2]n, the sodium salt of trans-2-nitrocinnamic acid, is a one-dimensional coordination polymer based on six-coordinate octahedral NaO6 centres comprising three facially-related monodentate carboxylate O-atom donors from separate ligands (all bridging)[Na-O, 2.4370(13)-2.5046(13)A] and three water molecules (two bridging, one monodentate) [Na-O, 2.3782(13)-2.4404(17)A]. The structure is also stabilized by intra-chain water-O-H...O(carboxylate) and O-H...O(nitro) hydrogen bonds.