我国开放式基金投资风格评价方法研究

基金业绩评价与其投资风格是密切相关的，投资者通过对基金投资风格的研究分类。可以选择适合于自己投资偏好的基金进行投资。本文在对开放式基金进行分类研究的基础上。抓住不同类型基金之间的主要差别，提出了两种新的基金风格评价指标。同时在我国现有的开放式基金中，选取15支样本进行了实证分析和检验，实证结果表明，我国开放式基金的投资风格趋于相同，投资者对于基金宣称的择时能力不可轻信。应该结合投资风格分析进行决策。     

On the impact of leverage constraints on asset prices and trading volume

Abstract. Researchers have used stylized facts on asset prices and trading volume in stock markets (in particular, the mean reversion of asset returns and the correlations between trading volume, price changes and price levels) to support theories where agents are not rational expected utility maximizers. This paper shows that this empirical evidence is in fact consistent with a standard infinite horizon – perfect information – expected utility economy where some agents face leverage constraints similar to those found in todays financial markets. In addition, and in sharp contrast to the theories above, we explain some qualitative differences that are observed in the price-volume relation on stock and on futures markets. We consider a continuous-time economy where agents maximize the integral of their discounted utility from consumption under both budget and leverage constraints. Building on the work by Vila and Zariphopoulou (1997), we find a closed form solution, up to a negative constant, for the equilibrium prices and demands in the region of the state space where the constraint is non-binding. We show that, at the equilibrium, stock holdings volatility as well as its ratio to stock price volatility are increasing functions of the stock price and interpret this finding in terms of the price-volume relation. We would like to thank the editor and two anonimous referees for valuable substantive comments. Our gratitude also to Franklin Allen, Kerry Back, Domenico Cuoco, Xavier Freixas, Sanford Grossman, Michel Habib, Lutz Hendricks, Richard Kihlstrom, Fernando Restoy, Mary Thomson, Jean-Luc Vila, participants to seminars at Birkbeck College, Carnegie-Mellon, Columbia, ESSEC, HEC, IAE, INSEAD, London Business School, London School of Economics, McGill, Michigan, National University of Singapore, Pompeu Fabra, North Carolina, Washington-St-Louis, Wharton, the Jornadas de Economía Financiera BBV, and the Meetings of the Society for Economic Dynamics and Control and the American Finance Association. Special thanks are due to Süleyman Basak for his enthusiastic support and many helpful suggestions. The usual disclaimer applies. We gratefully acknowledge the support of the BBV and Caja de Madrid Foundations and CREF (both authors) and of the Spanish Ministry of Education under DGICYT grant no. PB93-0388 (first author).     

Mean-variance hedging for interest rate models¶with stochastic volatility

The mean-variance hedging approach for pricing and hedging claims in incomplete markets was originally introduced for risky assets. The aim of this paper is to apply this approach to interest rate models in the presence of stochastic volatility, seen as a consequence of incomplete information. We fix a finite number of bonds such that the volatility matrix is invertible and provide an explicit formula for the density of the variance-optimal measure which is independent of the chosen times of maturity. Finally, we compute the mean-variance hedging strategy for a caplet and compare it with the optimal stategy according to the local risk minimizing approach. Received: 14 July 2000 / Accepted: 10 April 2001     

Productivity,earnings, and profit sharing — An econometric analysis of alternative models

The theoretical status of the relationship between productivity, wages, and profit sharing (PS) is poor. Only some alternative hypotheses can be formulated. From these explanations six different econometric models are derived. Using data of the German Socio-Economic Panel the models are estimated and tests and indicators are employed to choose the best model. Our investigation speaks in favour of hybrid simultaneous Tobit models where the level of profit sharing is positively correlated with productivity which induces positive wage effects on the one hand. But on the other hand the level of wages is also relevant to the question whether a firm introduces or decides to continuePS and which amount ofPS should be paid.What is obvious is not always true and introspection is a notoriously unreliable guide to empirical magnitudes. Blinder (1990, p.2)     

Gender differences in self‐employment

This paper examines the factors that influence transitions into self‐employment, paying particular attention to gender differences. We find that: (i) men are more responsive to the wage differential between wage/salaried employment and self‐employment; (ii) liquidity constraints are more important for men; and (iii) the link between father's self‐employment status and the probability of self‐employment is stronger for men. Taken together, these results suggest that, for women, self‐employment is a closer substitute for part‐time work and labour‐market inactivity than it is for men. We attribute such differences to the different labour market opportunities and occupational strategies of women.     

Time variation in the cointegrating relationship between stock prices and economic activity

The present paper examines whether there exists a long‐run cointegrating relationship between a stock market index and output and interest rates. Moreover, estimation is conducted over the full sample and both a recursive and rolling sample to examine any time variation in the nature of the relationship. The results support evidence of a single cointegrating vector, where stock prices typically exhibit a positive relationship with industrial production and a negative relationship with interest rates. However, there is significant time variation and periods of time where contrary results are observed. As such any model of stock prices needs to account for such time variation     

Employment shifts, economic reform and the changes in public/private sector wages in Mexico: 1987–1997

Over the last decade, the public sector in Mexico experienced substantial fiscal reform, divestiture of public enterprises, and the elimination of many regulations affecting pay and employment. This study analyzes the changes in the public/private sector differences in wages during the 1987–1997 period. The results from analyzing microdata from the Encuesta Nacional de Empleo Urbano show that relative public sector wages increased from 1987 to 1997. Most of the relative wage increase in the public sector can be explained by increases in the price of skills and by changes in sorting across sectors. The results have important public policy implications since they suggest that public sector workers earn more and their wages have grown faster than those of their private sector counterparts. As such, policies contemplating public sector reform should take into account the effect of these measures on the inter-sectoral income distribution and the overall economic growth. First version received: April 2000/Final version received: December 2000     

Contract renegotiation in a continuous state space

Summary. When players are unable to write complete state contingent contracts it is shown, within the context of a non-cooperative contracting-renegotiation game, that the only subgame perfect equilibrium allocations are those that correspond to the set of first-best allocations. Players are able to implement this set of allocations by signing an initial contract that is subsequently renegotiated in all states of the world. The contracting-renegotiation problem is complicated in an interesting way by assuming that the state space is continuous. The issue of the existence of an initial contract, that is subsequently renegotiated to the set of first-best allocations, must be resolved. Unlike Aghion, Dewatripont and Rey [1994], the results here do not require nor depend upon the comonotonicity of the objective functions. Received: January 27, 1995; revised version July 1, 1996     

Testing separability of public consumption in household decisions

In this paper we propose a sequential strategy, based on the microeconomic approach of the demand theory, in order to test for separability between private and public consumption. The aim of the present work is to verify, using a conditional almost ideal demand system, whether the different components of public consumption exert conditioning effects on the allocative structure of private spending. The empirical estimation of the model and the separability tests are developed for both a demand system in five functional categories of private spending, and for a demand system in six categories, where the private expenditures on those goods and services which can also be offered by the public sector are enclosed in a single functional category. The results of the separability tests, obtained using UK data for the 1974–2000 period, show that public individual consumption plays an important role in modifying consumer choices, while public collective consumption does not affect private consumption behaviours. The relationships between the different components of private spending and public individual consumption are both of substitutability and complementarity; in particular, we find that public individual consumption and the corresponding private expenditures on ‘Health, education, recreation and social protection’ are complements.     

Sample attrition and labor force dynamics: Evidence from the Spanish labor force survey

In this paper we examine a number of issues that arise in investigating labor force dynamics using the Spanish Labor Force Survey (EPA). These issues are by no means specific to the Spanish case and apply to most European-style labor force surveys. Our main conclusions may be summarized as follows. First, survey nonresponse cannot be neglected. Second, the EPA tends to underestimate employment and participation of high-educated young people, and to overestimate those of the low-educated elderly. Finally, we find little evidence that attrition causes important selection biases in estimating quarterly transition probabilities.