558 research outputs found
Representing Roomates' Preferences with Symmetric Utilities
Get PDFIn the context of the stable roommates problem, it is shown that acyclicity of preferences is equivalent to the existence of symmetric utility functions, i.e. the utility of agent i when matched with j is the same as j 's utility when matched with i .
Out-Of-The_Money Monte Carlo Simulation Option Pricing: the join use of Importance Sampling and Descriptive Sampling
Get PDFAs in any Monte Carlo application, simulation option valuation produces imprecise estimates. In such an application, Descriptive Sampling (DS) has proven to be a powerful Variance Reduction Technique. However, this performance deteriorates as the probability of exercising an option decreases. In the case of out of the money options, the solution is to use Importance Sampling (IS). Following this track, the joint use of IS and DS is deserving of attention. Here, we evaluate and compare the benefits of using standard IS method with the joint use of IS and DS. We also investigate the influence of the problem dimensionality in the variance reduction achieved. Although the combination IS+DS showed gains over the standard IS implementation, the benefits in the case of out-of-the-money options were mainly due to the IS effect. On the other hand, the problem dimensionality did not affect the gains. Possible reasons for such results are discussed.
Building Confidence Intervals with Block Bootstraps for the Variance Ratio Test of Predictability
Get PDFThis paper compares different versions of the multiple variance ratio test based on bootstrap techniques for the construction of empirical distributions. It also analyzes the crucial issue of selecting optimal block sizes when block bootstrap procedures are used, by applying the methods developed by Hall et al. (1995) and by Politis and White (2004). By comparing the results of the different methods using Monte Carlo simulations, we conclude that methodologies using block bootstrap methods present better performance for the construction of empirical distributions of the variance ratio test. Moreover, the results are highly sensitive to methods employed to test the null hypothesis of random walk.
The Effect of Bid-Ask Prices on Brazilian Options Implied Volatility: A Case Study of Telemar Call Options
Get PDFAlthough not explicitly reported, option traders on the Bovespa exchange pay an implicit bid-ask spread on each trade. Reported transaction prices that comprise the databases previously used to study the Brazilian options markets do not reflect actual option values at the time of the trades, but actual values plus (for purchases) or minus (for sales) the bid-ask spread. We use a chooser American option model to estimate Telemar call options bid-ask spreads, and to create a database of spread-adjusted trade prices. We find that the bid-ask spreads explain several previously reported puzzles regarding asset price volatility.
As cosmovisões pessimistas de Schopenhauer e Augusto dos Anjos
Get PDFDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão.O objetivo da dissertação é o de comparar as obras do filósofo alemão Arthur Schopenhauer e do poeta brasileiro Augusto dos Anjos, explorando os assuntos relativos ao pessimismo existente nelas. Eu mostro que os seguintes tópicos estão presentes na produção de ambos os autores: Schopenhauer e Augusto dos Anjos defendem que a dor é um importante constituinte do mundo, sendo perene; que a vida oscila, tal qual um pêndulo, entre o tédio e o sofrimento; que a natureza humana é malévola; que é pelo amor, pelo sexo e perpetuação da espécie que se prolonga o sofrimento humano no mundo; que a salvação e bem-aventurança só é possível através do ascetismo, do encontro com o nada
Long-Range Dependence in Exchange Rates: the case of the European Monetary System
Get PDFIn this work we measure the evolution of the long-range dependence phenomenon of returns and volatilities of nominal British exchange rates (British pound against US dollar) futures contracts negotiated on the Chicago Mercantile Exchange from 1986 to 2004. The measurement employs the R/S classic analysis, Detrended Fluctuation Analysis and Generalized Hurst exponents, upon a 1008-observation window, which moves along the data. We obtain as a result, the effects of the 1992 European financial crises on the measurements of the long-range dependency phenomenon. After the crisis the returns of this futures contract showed no signs of the long-range memory, which existed before the crisis. The volatility presented moderate long-range memory the whole time. We also test for long-memory in European currencies inside the European Monetary System and find evidence of moderate long memory, which suggests that being inside the EMS increases predictability.
Interdependence and Contagion: an Analysis of Information Transmission in Latin America's Stock Markets
Get PDFThis paper brings evidences about the hypotheses of financial crisis contagion over Latin American stock markets in the 90's using a multivariate GARCH model. Beside the traditional volatility structure, we added a leverage term like GJR framework in order to avoid problems due to the use of conditional correlation as a measure of relationship between stock markets. The results show the existence of contagion only during the Asian (1997) and the Russian (1998) crises. The consequences of the Brazilian crisis (1999) can be identified as a result of interdependence among Latin American markets, while the crises of Mexico (1994) and Argentina (2001) show a specific mechanism of propagation. This result raises questions about the "contagion" and "interdependence" concepts' adequacy for the analysis of information transmission among stock markets.
Speculative Attacks on Debts and Optimum Currency Area: A Welfare Analysis
Get PDFResorting to an extension of the debt crisis model of Cole and Kehoe (JIE 1996), we evaluate financial aspects of an optimum currency area. Our focus is to appraise the welfare of a country, which belongs to a monetary union and might suffer a speculative attack on its public debt. A default may be avoided by an inflation tax on common-currency debt, but this decision depends on majority voting and have costs associated with it. Moreover, the model considers symmetry between national and central governments' decisions about inflation and also describes the loss in international bankers' confidence towards one country being passed on to another. One of our results is that, for a country with low weight in the voting system, common-currency regime is superior in terms of expected welfare to dollarization and may be a better choice than the local-currency one, as the central bank under the latter regime undergoes some political influence from its government.
Comment on Market Discipline and Monetary Policy by Carl Walsh
Get PDFThis paper aims at correcting flaws in the way expectations are set in a paper by Walsh (2000) in order to assess with precision the impact of complex market rigidities and market expectations in the optimal choices of inflation in a monetary game between society and central bankers. After setting the expectations right, one of the results achieved indicates that the optimal inflation under any type of central banker is higher than that obtained in the original paper, suggesting that the time inconsistency phenomenon plays a more important role in explaining an inflationary bias than originally interpreted by Walsh (2000). However, if society organizes itself towards shorter tenure wage contracts, inflation will be lower. The results obtained for the output gap of the economy also differ from those achieved by Walsh in the sense that a central banker who is highly committed to previously announced inflation targets will have more opportunities to generate output growth above equilibrium rates and still commit. Finally, the stability of the premises regarding the contractual structure of the economy proposed by Walsh is tested under a game theoretic approach. The outcome of the test is that stability can be guaranteed only under strong assumptions and high symmetry in the sectoral distribution of firms. By using a social welfare function in which price surprises in any direction lead to welfare loss, the results indicate that society is better off by choosing longer tenure wage contracts, moving away from shorter tenure ones, at the cost of higher inflation.
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