Um modelo de competição baseada em tempo nos mercados financeiros

O objetivo deste trabalho é modelar o comportamento estratégico dos indivíduos diante de um choque estocástico que desloca o preço de determinado ativo financeiro do seu equilíbrio inicial. Investiga-se o caminho do preço de mercado em direção ao novo equilíbrio, conduzido pelas sucessivas negociações dos agentes em busca de oportunidades de obter lucros imediatos. Os operadores, que por suposição possuem funções de utilidade avessas ao risco, devem escolher a quantidade ótima transacionada e quanto devem aguardar para executar as suas ordens, tendo em vista a diminuição da volatilidade do preço do ativo à medida que as transações se sucedem após o choque. Procura-se demonstrar que os operadores que aceitam incorrer em riscos mais elevados negociam com maior frequência e em volumes e velocidades maiores, usufruindo lucros esperados mais altos que os demais.

Speculative attacks on debts and optimum currency area: a welfare analysis

Traditionally the issue of an optimum currency area is based on the theoretical underpinnings developed in the 1960s by McKinnon [13], Kenen [12] and mainly Mundell [14], who is concerned with the benefits of lowering transaction costs vis-à- vis adjustments to asymmetrical shocks. Recently, this theme has been reappraised with new aspects included in the analysis, such as: incomplete markets, credibility of monetary policy and seigniorage, among others. For instance, Neumeyer [15] develops a general equilibrium model with incomplete asset markets and shows that a monetary union is desirable when the welfare gains of eliminating the exchange rate volatility are greater than the cost of reducing the number of currencies to hedge against risks. In this paper, we also resort to a general equilibrium model to evaluate financial aspects of an optimum currency area. Our focus is to appraise the welfare of a country heavily dependent on foreign capital that may suffer a speculative attack on its public debt. The welfare analysis uses as reference the self-fulfilling debt crisis model of Cole and Kehoe ([6], [7] and [8]), which is employed here to represent dollarization. Under this regime, the national government has no control over its monetary policy, the total public debt is denominated in dollars and it is in the hands of international bankers. To describe a country that is a member of a currency union, we modify the original Cole-Kehoe model by including public debt denominated in common currency, only purchased by national consumers. According to this rule, the member countries regain some influence over the monetary policy decision, which is, however, dependent on majority voting. We show that for specific levels of dollar debt, to create inflation tax on common-currency debt in order to avoid an external default is more desirable than to suspend its payment, which is the only choice available for a dollarized economy when foreign creditors decide not to renew their loans.

Economia evolucionária e path dependence do investimento externo japonês: um estudo do Leste Asiático no período pré Segunda Guerra Mundial

A abertura da economia e o reinício das relações econômicas japonesas com o exterior e o processo de industrialização da economia japonesa na Era Meiji levaram o Japão a investir no exterior. Os investimentos japoneses no exterior cresceram preponderantemente no Leste Asiático, concentrando-se nessa área até o término da Segunda Guerra Mundial. A tese mostra que existem restrições de caráter institucional e histórico, que impõem limitações às empresas quanto ao leque de opções para investirem no exterior. Uma vez que as empresas japonesas fizeram a opção, impostas por aquelas restrições, de investir no Leste Asiático, feedbacks positivos, propiciados pelos eventos históricos e institucionais, geraram auto-reforços, levando a um resultado de inflexibilidade - lock-in - para sair dessa região. A tese comprova que explicar os investimentos externos japoneses pelo modelo de economia evolucionária, através do processo de path dependence, que incorpora o caráter institucional e histórico, é mais plausível do que as interpretações convencionais.

Speculative attacks on debts, dollarization and optimum currency areas

The purpose of this article is to contribute to the discussion of the financial aspects of dollarization and optimum currency areas. Based on the model of self-fulfilling debt crisis developed by Cole and Kehoe [4], it is possible to evaluate the comparative welfare of economies, which either keep their local currency and an independent monetary policy, join a monetary union or adopt dollarization. In the two former monetary regimes, governments can issue debt denominated, respectively, in local and common currencies, which is completely purchased by national consumers. Given this ability, governments may decide to impose an inflation tax on these assets and use the revenues so collected to avoid an external debt crises. While the country that issues its own currency takes this decision independently, a country belonging to a monetary union depends on the joint decision of all member countries about the common monetary policy. In this way, an external debt crises may be avoided under the local and common currency regimes, if, respectively, the national and the union central banks have the ability to do monetary policy, represented by the reduction in the real return on the bonds denominated in these currencies. This resource is not available under dollarization. In a dollarized economy, the loss of control over national monetary policy does not allow adjustments for exogenous shocks that asymmetrically affect the client and the anchor countries, but credibility is strengthened. On the other hand, given the ability to inflate the local currency, the central bank may be subject to the political influence of a government not so strongly concerned with fiscal discipline, which reduces the welfare of the economy. In a similar fashion, under a common currency regime, the union central bank may also be under the influence of a group of countries to inflate the common currency, even though they do not face external restrictions. Therefore, the local and common currencies could be viewed as a way to provide welfare enhancing bankruptcy, if it is not abused. With these peculiarities of monetary regimes in mind, we simulate the levels of economic welfare for each, employing recent data for the Brazilian economy.

Money supply and capital accumulation on the transition path revisited

Fischer (1979) and Asako (1983) analyze the sign of the correlation between the growth rate of money and the rate of capital accumulation on the transition path. Both plug a CRRA utility (based on a Cobb-Douglas and a Leontief function, respectively) into Sidrauski's model - yet return contrasting results. The present analysis, by using a more general CES utility, presents both of those settings and conclusions as limiting cases, and generates economic gures more consistent with reality (for instance, the interest-rate elasticity of the money demands derived from those previous works is necessarily 1 and 0, respectively).

Welfare characterization of monetary-applied models and three implications

This paper demonstrates that the applied monetary models - the Sidrauski-type models and the cash-in-advance models, augmented with a banking sector that supplies money substitutes services - imply trajectories which are Pareto-Optimum restricted to a given path of the real quantity of money. As a consequence, three results follow: First, Bailey’s formula to evaluate the welfare cost of inflation is indeed accurate, if the longrun capital stock does not depend on the inflation rate and if the compensate demand is considered. Second, the relevant money demand concept for this issue - the impact of inflation on welfare - is the monetary base. Third, if the long-run capital stock depends on the inflation rate, this dependence has a second-order impact on welfare, and, conceptually, it is not a distortion from the social point of view. These three implications moderate some evaluations of the welfare cost of the perfect predicted inflation.

A roughly smooth optimal consumption path: smoothing the rough annuity puzzle

A inconsistência entre a teoria e o comportamento empírico dos agentes no que tange ao mercado privado de pensões tem se mostrado um dos mais resistentes puzzles presentes na literatura econômica. Em modelos de otimização intertemporal de consumo e poupança sob incerteza em relação ao tempo de vida dos agentes, anuidades são ativos dominantes, anulando ou restringindo fortemente a demanda por ativos cujos retornos não estão relacionados à probabilidade de sobrevivência. Na prática, entretanto, consumidores são extremamente céticos em relação às anuidades. Em oposição ao seguro contra longevidade oferecido pelas anuidades, direitos sobre esses ativos - essencialmente ilíquidos - cessam no caso de morte do titular. Nesse sentido, choques não seguráveis de liquidez e a presença de bequest motives foram consideravelmente explorados como possíveis determinantes da baixa demanda verificada. Apesar dos esforços, o puzzle persiste. Este trabalho amplia a dominância teórica das anuidades sobre ativos não contingentes em mercados incompletos; total na ausência de bequest motives, e parcial, quando os agentes se preocupam com possíveis herdeiros. Em linha com a literatura, simulações numéricas atestam que uma parcela considerável do portfolio ótimo dos agentes seria constituída de anuidades mesmo diante de choques de liquidez, bequest motives, e preços não atuarialmente justos. Em relação a um aspecto relativamente negligenciado pela academia, mostramos que o tempo ótimo de conversão de poupança em anuidades está diretamente relacionado à curva salarial dos agentes. Finalmente, indicamos que, caso as preferências dos agentes sejam tais que o nível de consumo ótimo decaia com a idade, a demanda por anuidades torna-se bastante sensível ao sobrepreço (em relação àquele atuarialmente justo) praticado pela indústria, chegando a níveis bem mais compatíveis com a realidade empírica.

Welfare characterization of monetary-applied models and three implications

This paper demonstrates that the applied monetary mo deIs - the Sidrauski-type models and the cash-in-advance models, augmented with a banking sector that supplies money substitutes services - imply trajectories which are P8,reto-Optimum restricted to a given path of the real quantity of money. As a consequence, three results follow: First, Bailey's formula to evaluate the wclfare cost of inflation is indeed accurate, if the long-run capital stock does not depend on the inflation rate and if the compensate demand is considered. Second, the relevant money demand concept for this issue - the impact of inflation on welfare - is the monetary base, Third, if the long-run capital stock depends on the inflation rate, this dependence has a second-order impact ou wclfare, and, conceptually, it is not a distortion from tite social point of vicw. These three implications moderatc some evaluations of the wclfare cost of the perfect predicted inflation.