Nonparametric Sharpe Ratio

Sharpe ratio is a widely accepted tool for comparing the portfolio performance. In this paper we have proposed a nonparametric measure of the Sharpe rule. The statistical properties of this nonparametric measure and the standard Sharpe ratio are then developed under both normality and non-normality of observations. Further thebias corrected measures are given. An empirical application is also provided.

     

消费习惯、异质偏好与动态资产定价:纯交换经济情形

本文用Chan和Kogan、Bask和Cuoco等的方法考虑纯交换经济下的定价问题,我们引进了两个投资者:一个具有外在性消费习惯;一个不具有消费习惯。我们重点考察消费习惯对投资者的最优消费规则的影响以及对资产价格的确定。此外,我们还考虑了对数效用函数下,消费习惯以差的形式出现的情形下的消费规则和定价问题。我们发现当两个投资者中一个具有消费习惯而另一个不具有该习惯时,消费习惯同时改变两个投资者的最优消费规则、消费动态和财富动态。此时的动态资产定价受外在性消费习惯的影响,即时Sharpe比为常数,并等于同质量经济下的即时Sharpe比。同时,如果考虑对数效用函数下消费习惯以差的形式出现,则即时Sharpe比是时变的,反周期的。     

Portfolios in the Ibex 35 before and after the Global Financial Crisis

In this article, we present an analysis of the effectiveness of various portfolio optimization strategies applied to the stocks included in the Spanish Ibex 35 index, for a period of 14 years, from 2001 until 2014. The period under study includes episodes of volatility and instability in financial markets, incorporating the Global Financial Crisis and the European Sovereign Debt Crisis. This implies a challenge in portfolio optimization strategies since the methodologies are restricted to the assignment of positive weights. We have taken for asset allocation the daily returns with an estimation window equal to 1 year and we hold portfolio assets for another year. This article attempts to influence the discussion over whether the naive diversification proves to be an effective strategy as opposed to portfolio optimization models. For that, we evaluate the out-of-sample performance of 15 strategies for asset allocation in the Ibex 35, before and after of the Global Financial Crisis. Our results suggest that a large number of strategies outperform to the 1/N rule and to the Ibex 35 index in terms of return, Sharpe ratio and lower VaR and CVaR. The mean-variance portfolio of Markowitz with short-sale constraints is the only strategy that renders a Sharpe ratio statistically different from Ibex 35 index in the 2001–2007 and 2008–2014 time periods.     

Evaluation by the Aumann and Serrano performance index and Sharpe ratio: Bitcoin performance

We compare Bitcoin performance based on the Aumann and Serrano performance index and Sharpe ratio assuming that asset returns follow the class of discrete normal mixture distributions. The Aumann and Serrano performance index can take into account higher moments of the underlying distribution of assets and is relevant for risk-averse investors. We evaluate Bitcoin performance based on the Aumann and Serrano index relative to the performance of other assets. Our evaluation shows that Bitcoin is rated highly by the Sharpe ratio but rated very poorly by the Aumann and Serrano index. We also find some stock assets can beat Bitcoin by the Sharpe ratio when an investment horizon is monthly.     

Combining the minimum-variance and equally-weighted portfolios: Can portfolio performance be improved?

It is documented in the literature that due to estimation errors, mean-variance efficient portfolios deliver no higher out-of-sample Sharpe ratios than does the naïve equally-weighted portfolio (EWP). This paper demonstrates how the out-of-sample performance of the minimum-variance portfolio (MVP) can be improved in the presence of estimation errors by combining the MVP and EWP. Our results indicate that an appropriate combination of the MVP and EWP can enhance Sharpe ratios under any scenarios considered, and can also reduce the portfolio risk if short-selling is allowed. However, the combination strategy is not able to generate a lower risk level than the MVP when a short-selling restriction is imposed. We find that the optimal combination coefficient depends on the factors that greatly impact estimation errors in the MVP, including sample size, estimation method, no-short-selling restriction, and length of the out-of-sample period under consideration.     

Managed Futures for Long‐Term Investors: A DEA Ranking Analysis

This study proposes an alternative Data Envelopment Analysis ranking model to evaluate the relative performance efficiency of commodity‐trading advisors. I measure the performance efficiency using the decision‐making process quality/trading skills framework and depart from the traditional risk–return framework. The Data Envelopment Analysis rankings produced some interesting results. First, similarly to the previous studies, I successfully isolated two ‘superstar’ commodity‐trading advisors with the highest Sharpe ratios as the Grade A commodity‐trading advisors. However, as an improvement over the similar studies that used the traditional risk–return framework, I also isolated two commodity‐trading advisors with average and below‐average Sharpe ratios as Grade A commodity‐trading advisors.     

Prospect theory and liquidation decisions

We solve a liquidation problem for an agent with preferences consistent with the prospect theory of Kahneman and Tversky [Econometrica 47 (1979) 263-291]. We find that the agent is willing to hold a risky project with a relatively inferior Sharpe ratio if the project is currently making losses, and intends to liquidate it when it breaks even. On the other hand, the agent may liquidate a project with a relatively superior Sharpe ratio if its current profits rise or drop to the break-even point. Our results capture the spirit of the disposition effect and the break-even effect documented in empirical and experimental studies.     

Asset pricing with idiosyncratic risk and overlapping generations

What is the effect of non-tradeable idiosyncratic risk on asset-market risk premiums? Constantinides and Duffie [Constantinides, G.M., Duffie, D., 1996. Asset pricing with heterogeneous consumers. Journal of Political Economy 104, 219–240] and Mankiw [Mankiw, N.G., 1986. The equity premium and the concentration of aggregate shocks. Journal of Financial Economics 17, 211–219] have shown that risk premiums will increase if the idiosyncratic shocks become more volatile during economic contractions. We add two important ingredients to this relationship: (i) the life cycle, and (ii) capital accumulation. We show that in a realistically-calibrated life-cycle economy with production these ingredients mitigate the ability of idiosyncratic risk to account for the observed Sharpe ratio on US equity. While the Constantinides–Duffie model can account for the US value of 41% with a risk-aversion coefficient of 8, our model generates a Sharpe ratio of 33%, which is roughly half-way to the complete-markets value of 25%. Almost all of this reduction is due to capital accumulation. Life-cycle effects are important in our model—we demonstrate that idiosyncratic risk matters for asset pricing because it inhibits the intergenerational sharing of aggregate risk—but their net effect on the Sharpe ratio is small.     

Risk Diversification on the Polish Capital Market

The basics of portfolio management theory and methods of efficient selection of assets and their financing have been created by Markowitz and Sharpe. They propose that risk diversification consists, generally speaking, of the increase in the number of securities in a portfolio. So, authors try to answer the question of how many securities have to be bought on a given market to assure a well-diversified portfolio, where the increase in the number of securities does not lead to a significant decrease in portfolio risk. To evaluate such a purpose on the Polish capital market, 20 companies were surveyed that are included in the WIG20 index in the period January 2–October 10, 2001. The returns were estimated on a weekly basis. The research shows that a portfolio of securities constructed, according to the Sharpe Model, has a wide application to the Polish capital market.*University of Szczecin—Poland. This paper was presented at the Fifty-Eighth InternationalAtlantic Economic Conference, October 6Y9, 2005, Chicago, U.S.A.     

Optimizing tracking error-constrained portfolios

Active portfolios subject to tracking error (TE) constraints are the typical setup for active managers tasked with outperforming a benchmark. The risk and return relationship of such constrained portfolios is described by an ellipse in traditional mean-variance space and the ellipse’s flat shape suggests an additional constraint which improves the performance of the active portfolio. Although subsequent work isolated and explored different portfolios subject to these constraints, absolute portfolio risk has been consistently ignored. A different restriction – maximization of the traditional Sharpe ratio on the constant TE frontier in absolute risk/return space – is added here to the existing constraint set, and a method to generate this portfolio is explained. The resultant portfolio has a lower volatility and higher return than the benchmark, it satisfies the TE constraint and the ratio of excess absolute return to risk is maximized (i.e. maximum Sharpe ratio in absolute space).     

Stock and Industry Return Characteristics Around Price Shocks

The author investigates positive and negative price shocks in individual securities and the degree to which they affect related firms in the same industry. This price contagion effect is significant with initial price shocks leading to substantial long-term abnormal returns across firms in the same industry over time. Price shocks also have predictive value regarding future earnings and revenues for the firm in question and its industry overall. Positive (negative) price shocks that are continued over time are associated with higher (lower) Sharpe ratios suggesting that abnormal returns are not simply a form of compensation for greater expected future volatility.     

Two alternative stochastic specification and estimation methods for quantity rationing models: A Monte-Carlo comparison

Quantity rationing (disequilibrium) models can be characterized either by deterministic or by stochastic switching rules. This paper reports on Monte-Carlo experiments suggesting that the ML estimator associated with the deterministic switching rule one-market model apparently has better small sample properties than its stochastic switching rule counterpart even when the latter is asymptotically superior. This seems to be the result of a systematic residual variance underestimation in the stochastic switching rule model. The feasibility of the deterministic switching rule estimator in a two-market framework is next investigated.     

The monetary appreciation of paintings: from realism to Magritte

This study investigates how investments in paintings comparewith those in stocks in terms of risk–return trade-offusing Sharpe and Treynor ratios and Markowitz efficient frontiers.A large database was analysed consisting of more than 10,500auction prices of Belgian paintings over the period 1970–97.These paintings are the auctioned oeuvre of 71 internationallyrecognised painters representing the main artistic schools (fromsocial realism to surrealism) over the period 1850–1950.Hedonic art returns are corrected for auction location and auctionhouse, artistic school, painters' reputation, medium, signatureand painting size. Surrealism and luminism have been the mostpopular currents of art (in monetary terms), while expressionismand symbolism have gained (financial) esteem. This study concludesthat art investments underperform equity market investmentsowing to the high risk of investing in art and its high transactioncosts, resale rights and insurance premia. In addition, theMarkowitz efficient frontier shows limited diversification potentialfor art.     

The Costs of Implementing the Majority Principle: The Golden Voting Rule

In a context of constitutional choice of a voting rule, this paper presents an economic analysis of scoring rules that identifies the golden voting rule under the impartial culture assumption. This golden rule depends on the weights β and (1−β) assigned to two types of costs: the cost of majority decisiveness (‘tyranny’) and the cost of the ‘erosion’ in the majority principle. Our first main result establishes that in voting contexts where the number of voters n is typically considerably larger than the number of candidates k, the golden voting rule is the inverse plurality rule for almost any positive β. Irrespective of n and k, the golden voting rule is the inverse plurality rule if β ≥ 1/2 .. This hitherto almost unnoticed rule outperforms any other scoring rule in eliminating majority decisiveness. The golden voting rule is, however, the plurality rule, the most widely used voting rule that does not allow even the slightest ‘erosion’ in the majority principle, when β=0. Our second main result establishes that for sufficiently “small size” voting bodies, the set of potential golden rules consists at most of just three rules: the plurality rule, the Borda rule and the inverse plurality rule. On the one hand, this finding provides a new rationalization to the central role the former two rules play in practice and in the voting theory literature. On the other hand, it provides further support to the inverse plurality rule; not only that it is the golden rule in voting contexts, it also belongs, together with the plurality rule and the Borda method of counts, to the “exclusive” set of potential golden voting rules in small committees. We are indebted to Jim Buchanan, Amichai Glazer, Noa Nitzan, Ken Shepsle, and an anonymous referee for their useful comments.     

The golden rule of public finance and the composition of government expenditures: a growth and welfare analysis

This paper employs an endogenous growth model to study the growth and welfare effects of the golden rule of public finance. Two versions are compared, whereby government deficits are restricted for the use of public investments. It is shown that the growth effect of the golden rule depends on what kind of expenditure is adjusted to meet debt obligations. A transition from a balanced budget to a golden rule is performed to study welfare. The results indicate that a budget rule with detrimental growth effects can still have positive welfare implications, and vice versa, if the composition of government expenditures and transitional dynamics are taken into account.     

动量思想与大宗商品的战术配置价值*——基于Black Litterman模型

本文讨论了大宗商品的战术资产配置价值。通过利用1973—2016年的季度数据，笔者提出了基于动量思想的Black Litterman配置模型。该配置模型表明，在传统股票债券组合中加入GSCI大宗商品指数会明显改善组合的回报。在适当的策略周期下，加入大宗商品指数还能够提高组合的夏普比。这表明，大宗商品指数的战术配置价值明显。与其他常见的配置模型相比，本文提出的基于动量思想的Black Litterman模型表现相对较好。上述发现在经过交易成本调整后仍然成立。     

Unique monetary equilibria with interest rate rules: An extension

In a recent paper, Adão et al. (2011), using a cash-in-advance framework, derive an interest rate rule that results in a unique monetary equilibrium. The resulting interest rate rule is forward looking and the interest rate responds positively to forecasts of future real activity and to forecasts of the future price level. This paper extends their approach to a transactions cost environment. The resulting interest rate rule has the added feature that, in line with previous studies, the nominal interest rate responds positively to forecasts of future inflation.     

Book Review

Mark H. Maier. The Data Game: Controversies in Social Science Statistics, 3rd ed. Armonk, N.Y.: M. E. Sharpe, 1999. 332 pp.     

Reuters Sentiment and Stock Returns

Sentiment from more than 3.6 million Reuters news articles is tested in a vector autoregression model framework on its ability to forecast returns of the Dow Jones Industrial Average stock index. We show that Reuters sentiment can explain and predict changes in stock returns better than macroeconomic factors. We further find that negative Reuters sentiment has more predictive power than positive Reuters sentiment. Trading strategies with Reuters sentiment achieve significant outperformance with high success rates as well as high Sharpe ratios.