859 resultados para conditional expected utility
Resumo:
This paper proposes a two-step procedure to back out the conditional alpha of a given stock using high-frequency data. We rst estimate the realized factor loadings of the stocks, and then retrieve their conditional alphas by estimating the conditional expectation of their risk-adjusted returns. We start with the underlying continuous-time stochastic process that governs the dynamics of every stock price and then derive the conditions under which we may consistently estimate the daily factor loadings and the resulting conditional alphas. We also contribute empiri-cally to the conditional CAPM literature by examining the main drivers of the conditional alphas of the S&P 100 index constituents from January 2001 to December 2008. In addition, to con rm whether these conditional alphas indeed relate to pricing errors, we assess the performance of both cross-sectional and time-series momentum strategies based on the conditional alpha estimates. The ndings are very promising in that these strategies not only seem to perform pretty well both in absolute and relative terms, but also exhibit virtually no systematic exposure to the usual risk factors (namely, market, size, value and momentum portfolios).
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In this paper, we propose a class of ACD-type models that accommodates overdispersion, intermittent dynamics, multiple regimes, and sign and size asymmetries in financial durations. In particular, our functional coefficient autoregressive conditional duration (FC-ACD) model relies on a smooth-transition autoregressive specification. The motivation lies on the fact that the latter yields a universal approximation if one lets the number of regimes grows without bound. After establishing that the sufficient conditions for strict stationarity do not exclude explosive regimes, we address model identifiability as well as the existence, consistency, and asymptotic normality of the quasi-maximum likelihood (QML) estimator for the FC-ACD model with a fixed number of regimes. In addition, we also discuss how to consistently estimate using a sieve approach a semiparametric variant of the FC-ACD model that takes the number of regimes to infinity. An empirical illustration indicates that our functional coefficient model is flexible enough to model IBM price durations.
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This paper assesses whether eligibility for conditional cash transfer programs have been manipulated, as well as the impact of this phenomenon on time allocation within households. To perform this analysis, we use data from the 2006 PNAD (Brazilian national household survey) and investigate the eligibility manipulation for the Bolsa Família (Family Stipend) program during this time period. The program assists families with a monthly per capita income of around R$120.00 (US$60.00). By applying the tests developed by McCrary (2008), we find suggestive evidence that individuals manipulate their income by voluntarily reducing their labor supply in order to become eligible to the program. Moreover, the reduction in labor supply is greater among women, especially single or divorced mothers. This evidence raises some concern about the unintended consequences related to the eligibility criteria utilized by Bolsa Família, as well as the program’s impact on individuals living in extreme poverty.
Resumo:
We study the effects of a conditional transfers program on school enrollment and performance in Mexico. We provide a theoretical framework for analyzing the dynamic educational decision and process inc1uding the endogeneity and uncertainty of performance (passing grades) and the effect of a conditional cash transfer program for children enrolled at school. Careful identification of the program impact on this model is studied. This framework is used to study the Mexican social program Progresa in which a randomized experiment has been implemented and allows us to identify the effect of the conditional cash transfer program on enrollment and performance at school. Using the mIes of the conditional program, we can explain the different incentive effects provided. We also derive the formal identifying assumptions needed to provide consistent estimates of the average treatment effects on enrollment and performance at school. We estimate empirically these effects and find that Progresa had always a positive impact on school continuation whereas for performance it had a positive impact at primary school but a negative one at secondary school, a possible consequence of disincentives due to the program termination after the third year of secondary school.
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This paper deals with the estimation and testing of conditional duration models by looking at the density and baseline hazard rate functions. More precisely, we foeus on the distance between the parametric density (or hazard rate) function implied by the duration process and its non-parametric estimate. Asymptotic justification is derived using the functional delta method for fixed and gamma kernels, whereas finite sample properties are investigated through Monte Carlo simulations. Finally, we show the practical usefulness of such testing procedures by carrying out an empirical assessment of whether autoregressive conditional duration models are appropriate to oIs for modelling price durations of stocks traded at the New York Stock Exchange.
Resumo:
We use the Ramsey model of g,Towth elaborated by Bliss [1995] and Ventlira [1997] to show how international integration results in long-nm persistellce Df GNPs distribution, while allowing, under certain conditions on parameters, for convergellce during the transition. First, we pi·ovide relationships which explicitly relate, in the neighborhood of the steady-state, the magnitude of conditional convergence or divergence to the fundamentaIs of the economies. Second, we present ali analysis of the Cobb Douglas case with a broad dass of utility functions and show that there is always transitional convergenee with this technology. Third, directions for testing the Illodel against the traditional dosed-ecollomy setting are proposed. These lead to adding specific and world-wide regTessors to traditional growth regressions.
Resumo:
The estimation of labor supply elasticities has been an important issue m the economic literature. Yet all works have estimated conditional mean labor supply functions only. The objective of this paper is to obtain more information on labor supply, by estimating the conditional quantile labor supply function. vI/e use a sample of prime age urban males employees in Brazil. Two stage estimators are used as the net wage and virtual income are found to be endogenous to the model. Contrary to previous works using conditional mean estimators, it is found that labor supply elasticities vary significantly and asymmetrically across hours of work. vVhile the income and wage elasticities at the standard work week are zero, for those working longer hours the elasticities are negative.
Resumo:
In this paper we study the dynamic hedging problem using three different utility specifications: stochastic differential utility, terminal wealth utility, and we propose a particular utility transformation connecting both previous approaches. In all cases, we assume Markovian prices. Stochastic differential utility, SDU, impacts the pure hedging demand ambiguously, but decreases the pure speculative demand, because risk aversion increases. We also show that consumption decision is, in some sense, independent of hedging decision. With terminal wealth utility, we derive a general and compact hedging formula, which nests as special all cases studied in Duffie and Jackson (1990). We then show how to obtain their formulas. With the third approach we find a compact formula for hedging, which makes the second-type utility framework a particular case, and show that the pure hedging demand is not impacted by this specification. In addition, with CRRA- and CARA-type utilities, the risk aversion increases and, consequently the pure speculative demand decreases. If futures price are martingales, then the transformation plays no role in determining the hedging allocation. We also derive the relevant Bellman equation for each case, using semigroup techniques.
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The objective of this paper is to evaluate the effect of the 1985 ”Employment Services for Ex-Offenders” (ESEO) program on recidivism. Initially, the sample has been split randomly in a control group and a treatment group. However, the actual treatment (mainly being job related counseling) only takes place conditional on finding a job, and not having been arrested, for those selected in the treatment group. We use a multiple proportional hazard model with unobserved heterogeneity for job seach and recidivism time which incorporates the conditional treatment effect. We find that the program helps to reduce criminal activity, contrary to the result of the previous analysis of this data set. This finding is important for crime prevention policy.
Resumo:
Cash transfers targeted to poor people, but conditional on some behavior on their part, such as school attendance or regular visits to health care facilities, are being adopted in a growing number of developing countries. Even where ex-post impact evaluations have been conducted, a number of policy-relevant counterfactual questions have remained unanswered. These are questions about the potential impact of changes in program design, such as benefit levels or the choice of the means-test, on both the current welfare and the behavioral response of household members. This paper proposes a method to simulate the effects of those alternative program designs on welfare and behavior, based on microeconometrically estimated models of household behavior. In an application to Brazil’s recently introduced federal Bolsa Escola program, we find a surprisingly strong effect of the conditionality on school attendance, but a muted impact of the transfers on the reduction of current poverty and inequality levels.
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In a two-period economy with incomplete markets and possibility of default we consider the two classical ways to enforce the honor of financial commitments: by using utility penalties and by using collateral requirements that borrowers have to fulfill. Firstly, we prove that any equilibrium in an economy with collateral requirements is also equilibrium in a non-collateralized economy where each agent is penalized (rewarded) in his utility if his delivery rate is lower (greater) than the payment rate of the financial market. Secondly, we prove the converse: any equilibrium in an economy with utility penalties is also equilibrium in a collateralized economy. For this to be true the payoff function and initial endowments of the agents must be modified in a quite natural way. Finally, we prove that the equilibrium in the economy with collateral requirements attains the same welfare as in the new economy with utility penalties.
Resumo:
This paper develops a general method for constructing similar tests based on the conditional distribution of nonpivotal statistics in a simultaneous equations model with normal errors and known reducedform covariance matrix. The test based on the likelihood ratio statistic is particularly simple and has good power properties. When identification is strong, the power curve of this conditional likelihood ratio test is essentially equal to the power envelope for similar tests. Monte Carlo simulations also suggest that this test dominates the Anderson- Rubin test and the score test. Dropping the restrictive assumption of disturbances normally distributed with known covariance matrix, approximate conditional tests are found that behave well in small samples even when identification is weak.
Resumo:
Esta tese é constituída por três ensaios. O primeiro ensaio analisa a informação pública disponível sobre o risco das carteiras de crédito dos bancos brasileiros, sendo dividido em dois capítulos. O primeiro analisa a limitação da informação pública disponibilizada pelos bancos e pelo Banco Central, quando comparada a informação gerencial disponível internamente pelos bancos. Concluiu-se que existe espaço para o aumento da transparência na divulgação das informações, fato que vem ocorrendo gradativamente no Brasil através de novas normas relacionadas ao Pilar 3 de Basileia II e à divulgação de informações mais detalhas pelo Bacen, como, por exemplo, aquelas do “Top50” . A segunda parte do primeiro ensaio mostra a discrepância entre o índice de inadimplência contábil (NPL) e a probabilidade de inadimplência (PD) e também discute a relação entre provisão e perda esperada. Através da utilização de matrizes de migração e de uma simulação baseada na sobreposição de safras de carteira de crédito de grandes bancos, concluiu-se que o índice de inadimplência subestima a PD e que a provisão constituída pelos bancos é menor que a perda esperada do SFN. O segundo ensaio relaciona a gestão de risco à discriminação de preço. Foi desenvolvido um modelo que consiste em um duopólio de Cournot em um mercado de crédito de varejo, em que os bancos podem realizar discriminação de terceiro grau. Neste modelo, os potenciais tomadores de crédito podem ser de dois tipos, de baixo ou de alto risco, sendo que tomadores de baixo risco possuem demanda mais elástica. Segundo o modelo, se o custo para observar o tipo do cliente for alto, a estratégia dos bancos será não discriminar (pooling equilibrium). Mas, se este custo for suficientemente baixo, será ótimo para os bancos cobrarem taxas diferentes para cada grupo. É argumentado que o Acordo de Basileia II funcionou como um choque exógeno que deslocou o equilíbrio para uma situação com maior discriminação. O terceiro ensaio é divido em dois capítulos. O primeiro discute a aplicação dos conceitos de probabilidade subjetiva e incerteza Knigthiana a modelos de VaR e a importância da avaliação do “risco de modelo”, que compreende os riscos de estimação, especificação e identificação. O ensaio propõe que a metodologia dos “quatro elementos” de risco operacional (dados internos, externos, ambiente de negócios e cenários) seja estendida à mensuração de outros riscos (risco de mercado e risco de crédito). A segunda parte deste último ensaio trata da aplicação do elemento análise de cenários para a mensuração da volatilidade condicional nas datas de divulgação econômica relevante, especificamente nos dias de reuniões do Copom.
Resumo:
This paper investigates the role of consumption-wealth ratio on predicting future stock returns through a panel approach. We follow the theoretical framework proposed by Lettau and Ludvigson (2001), in which a model derived from a nonlinear consumer’s budget constraint is used to settle the link between consumption-wealth ratio and stock returns. Using G7’s quarterly aggregate and financial data ranging from the first quarter of 1981 to the first quarter of 2014, we set an unbalanced panel that we use for both estimating the parameters of the cointegrating residual from the shared trend among consumption, asset wealth and labor income, cay, and performing in and out-of-sample forecasting regressions. Due to the panel structure, we propose different methodologies of estimating cay and making forecasts from the one applied by Lettau and Ludvigson (2001). The results indicate that cay is in fact a strong and robust predictor of future stock return at intermediate and long horizons, but presents a poor performance on predicting one or two-quarter-ahead stock returns.