Short note on inf-convolution preserving the Fatou property

We model agents’ preferences by cash-invariant concave functionals defined on L ^∞, and formulate the optimal risk allocation problem as their infimal-convolution. We study the case of agents whose choice functionals are law-invariant with respect to different probability measures and show how, in this case, the value function preserves a desirable dual representation (equivalent to the Fatou property). Financial support from the European Science Foundation (ESF) “Advanced Mathematical Methods for Finance” (AMaMeF) under the exchange grant 1192 is gratefully acknowledged.     

A note on essential smoothness in the Heston model

This note identifies a gap in the proof of Corollary 2.4 in Forde and Jacquier (Finance Stoch., 2011) which arises because the essential smoothness of the family (X _t /t) _t≥1 can fail for the log-spot process X in the Heston model, and it describes how to circumvent the issue by applying a standard argument from large deviation theory.     

An early pricing model regarding the value of a cat: A historical note

Have you ever worried about how much your cat was worth? The ancient Welsh had a formalized system for cat valuation. This system, however, illustrates that the Welsh recognized and faced many of the same vexing problems facing today's valuation theorists.     

A note on Wick products and the fractional Black-Scholes model

In some recent papers (Elliott and van der Hoek 2003; Hu and Øksendal 2003) a fractional Black-Scholes model has been proposed as an improvement of the classical Black-Scholes model (see also Benth 2003; Biagini et al. 2002; Biagini and Øksendal 2004). Common to these fractional Black-Scholes models is that the driving Brownian motion is replaced by a fractional Brownian motion and that the Itô integral is replaced by the Wick integral, and proofs have been presented that these fractional Black-Scholes models are free of arbitrage. These results on absence of arbitrage complelety contradict a number of earlier results in the literature which prove that the fractional Black-Scholes model (and related models) will in fact admit arbitrage. The objective of the present paper is to resolve this contradiction by pointing out that the definition of the self-financing trading strategies and/or the definition of the value of a portfolio used in the above papers does not have a reasonable economic interpretation, and thus that the results in these papers are not economically meaningful. In particular we show that in the framework of Elliott and van der Hoek 2003, a naive buy-and-hold strategy does not in general qualify as self-financing. We also show that in Hu and Øksendal 2003, a portfolio consisting of a positive number of shares of a stock with a positive price may, with positive probability, have a negative value.Received: August 2004, Mathematics Subject Classification (2000): 91B28, 60H05JEL Classification: G10Support of the first author from the Jan Wallander and Tom Hedelius foundation is gratefully acknowledged. The research of the second author is supported by the Swedish Research Council.     

A note on the efficiency of the binomial option pricing model

We discuss the efficiency of the binomial option pricing model for single and multivariate American style options. We demonstrate how the efficiency of lattice techniques such as the binomial model can be analysed in terms of their computational cost. For the case of a single underlying asset the most efficient implementation is the extrapolated jump-back method: that is, to value a series of options with nested discrete sets of early exercise opportunities by jumping across the lattice between the early exercise times and then extrapolating from these values to the limit of a continuous exercise opportunity set. For the multivariate case, the most efficient method depends on the computational cost of the early exercise test. However, for typical problems, the most efficient method is the standard step-back method: that is, performing the early exercise test at each time step.     

Best-performing US mutual fund families from 1993 to 2008: Evidence from a novel two-stage DEA model for efficiency decomposition

When analyzing relative performance, especially at the institutional level, the traditional data envelopment analysis (DEA) models do not recognize vastly different and important activities as separate functions and therefore cannot identify which function may be the main source of inefficiency. We propose a novel two-stage DEA model that decomposes the overall efficiency of a decision-making unit into two components and demonstrate its applicability by assessing the relative performance of 66 large mutual fund families in the US over the period 1993–2008. By decomposing the overall efficiency into operational management efficiency and portfolio management efficiency components, we reveal the best performers, the families that deteriorated in performance, and those that improved in their performance over the sample period. We also make frontier projections for poorly performing mutual fund families and highlight how the portfolio managers have managed their funds relative to the others during financial crisis periods.     

Persistence and the four‐factor model in the Australian funds market: a note

We investigate whether Australian fund managers are able to deliver persistent performance using Carhart’s (1997) four‐factor model. Short‐ and long‐term persistence is examined and the sample is also divided into unit trusts and superannuation funds. We do not find evidence of persistence in any sample of funds. We find that winner (loser) funds tend to hold past winner (loser) stocks. Winner and loser unit trusts both appear to have positive exposure to small stocks.     

A note on the properties of a test procedure for discrimination between two types of spectra of a stationary process

Abstract

1. Introduction and Summary

The spectral analysis plays an important rôle in the study of stationary stochastic process. It cannot, however, always, be assumed that the nature of the corresponding spectral function is known a priori—we are then faced with two problems. In the first we may have either a discrete spectrum plus a uniform noise or a continuous spectrum and in the second we may have both at the same time. A possible method has been suggested by Whittle [5] as a solution to the second problem. A discriminatory test based on the likelihood ratio has been put forward by Bartlett as a solution to the first problem which is an important one occurring in practice. The test procedure was applied to two suitable artificial series. The test, when applied, to a series with a harmonic element resulted in the failure to arrive atadecision. An investigation was then made on the applicability of this test to such series in general.     

The consumption based asset pricing model: A note on potential tests and applications

Breeden's demonstration that Merton's multi-beta capital asset pricing model can be collapsed into a single-beta model where betas are computed with respect to aggregate consumption is an important theoretical advance. Nonetheless, Breeden's model retains many of the empirical problems that beset Merton's earlier version. In general the consumption betas will be nonstationary, so that the state variables must be observable for the model to be estimated.     

追偿在巴西：运用快速执行程序

为更好地运用快速执行程序,中国出口商首先要争取事先获得可执行文件,以此增强对买方的威慑;其次在发生风险后要积极主张,尽全力保障自身权益随着中国和巴西经贸合作的不断发展,中国已经成为巴西最大贸易伙伴、最大出口目的地国和第二大进口来源国。     

Short sale constraints: the impact on the return distribution

This paper tests empirically Hong and Stein's theoretical finding, that in an environment of short sale constraints, investor disagreement over future equity prices leads to negatively skewed return distributions. This study uses data from the Indian equity market to examine the third and fourth moments of the return distribution. The skewness of the return distribution is estimated both from realized returns and option prices. Empirical results provide partial supportive evidence for Hong and Stein's hypothesis.     

Short Selling and the Weekend Effect for NYSE Securities

Using short-sale transactions data, we examine the relation between short selling and the weekend effect. We do not find that short selling is more abundant on Monday than on Friday, even for stocks that have higher Friday returns. We find that short sellers execute more short-sale volume during the middle of the week, and that the positive correlation between short selling and returns on Monday is greater, on average, than the correlation on the other days of the week. Our results are robust to subsamples of stocks with larger weekend effects and stocks that do not have listed options.     

A note on cross-impact analysis: a calculus for sequence-dependent events

As the example presented demonatrate, the analysis of cross-impactss amount a group of related events is somewhat more complex than perhaps heretofore imagined. Impacts of effects between such events very often carely depend on their temporal sequence. The event outcome space is accordingly multiplied considerably over the case where such dependency is ignored. The result is that high premium is placed on methods that seek to reduce analytical complexity without distorting essential event intrications.     

Short and long-term interactions between venture capital returns and the macroeconomy: evidence for the United States

The main purpose of this paper is to empirically model the influence of macroeconomic and financial variables on the performance of risk capital in the US. We start our investigation using a static long-run equilibrium model. In contrast to previous studies, we analyze the effect of several factors simultaneously within the framework of a vector error correction model (VECM). This allows us to study short- and long-term interactions to overcome the problem of endogeneity, and to discover causal mechanisms. The results show that the value of venture capital investments is positively related to industrial production, the exit channel Nasdaq, and the long-term interest rate. However, the value of venture capital investments is negatively related to the short-term interest rate. According to the short-term dynamics, VEC Granger causality confirms that only industrial production influences venture capital performance, while venture capital returns Granger causes Nasdaq performance.     

Non-concavity problems in the dynamic macroeconomic models: A note

This note provides a method to convert the dynamic models in Cysne [Cysne, Rubens P., 2006. A note on the non-convexity problem in some shopping-time and human-capital models. Journal of Banking and Finance 30 (10), 2737–2745] and in Cysne [Cysne, Rubens P., 2008. A note on “inflation and welfare”. Journal of Banking and Finance 32 (9), 1984–1987] to concave optimization problems. We do this by introducing new control and state variables in the models. Cysne (2006, 2008) restrict attention to continuous time models and derive parametric conditions to use Arrow’s sufficiency theorem. When the sufficient conditions presented in Cysne (2006) are satisfied (but not under the sharper sufficient conditions presented in Cysne (2008)) we can rewrite these models as concave optimization problems even if time is discrete.     

On a historical note: the legacy of Thomas Hodgkin

Physicians in the practice of insurance medicine are exposed to an unbelievable spectrum of pathology. This series of short biographies is intended to give the reader a quick overview of the history of diseases encountered in our everyday practice and to see "the face behind the name." In the first article of this series, I wish to pay homage to one of the "great men of Guy's," Dr. Thomas Hodgkin.     

Interest rate dynamics and the term structure: A note

The Brennan and Schwartz two-factor model of the term structure is re-examined using constant-duration long-term yields in place of the fluctuating-duration consol yields, and additional stability is achieved in the empirical estimations. The model is then reformulated to examine more closely the relationship between changes in long and short rates of interest. It is found that movements in the short rate of interest are related to movements in the long rate, the spread between the long and short rates, and the prior movement in the long rate. The model is then tested for its out-of-sample predictive ability and found to possess a modest amount of predictive power.     

Efficiency and the Bear: Short Sales and Markets Around the World

We analyze cross‐sectional and time‐series information from 46 equity markets around the world to consider whether short sales restrictions affect the efficiency of the market and the distributional characteristics of returns to individual stocks and market indices. We find some evidence that prices incorporate negative information faster in countries where short sales are allowed and practiced. A common conjecture by regulators is that short sales restrictions can reduce the relative severity of a market panic. We find strong evidence that in markets where short selling is either prohibited or not practiced, market returns display significantly less negative skewness.