UNIVERSAL SEMICONSTANT REBALANCED PORTFOLIOS

In this paper, we investigate investment strategies that can rebalance their target portfolio vectors at arbitrary investment periods. These strategies are called semiconstant rebalanced portfolios in Blum and Kalai and Helmbold et al. Unlike a constant rebalanced portfolio, which must rebalance at every investment interval, a semiconstant rebalanced portfolio rebalances its portfolio only on selected instants. Hence, a semiconstant rebalanced portfolio may avoid rebalancing if the transaction costs outweigh the benefits of rebalancing. In a competitive algorithm framework, we compete against all such semiconstant portfolios with an arbitrary number of rebalancings and corresponding rebalancing instants. We investigate this framework with and without transaction costs and demonstrate sequential portfolios that asymptotically achieve the wealth of the best semiconstant rebalanced portfolios whose number of rebalancings and instants of rebalancings are tuned to the individual sequence of price relatives.     

Arbitrage and Growth Rate for Riskless Investments in a Stationary Economy

A sequential investment is a vector of payments over time, ( a ₀, a ₁, ... , a_n ), where a payment is made to or by the investor according as a_i is positive or negative. Given a collection of such investments it may be possible to assemble a portfolio from which an investor can get "something for nothing," meaning that without investing any money of his own he can receive a positive return after some finite number of time periods. Cantor and Lipmann (1995) have given a simple necessary and sufficient condition for a set of investments to have this property. We present a short proof of this result. If arbitrage is not possible, our result leads to a simple derivation of the expression for the long–run growth rate of the set of investments in terms of its "internal rate of return."     

Who should sell stocks?

Never selling stocks is optimal for investors with a long horizon and a realistic range of preference and market parameters, if relative risk aversion, investment opportunities, proportional transaction costs, and dividend yields are constant. Such investors should buy stocks when their portfolio weight is too low and otherwise hold them, letting dividends rebalance to cash over time rather than selling. With capital gains taxes, this policy outperforms both static buy‐and‐hold and dynamic rebalancing strategies that account for transaction costs. Selling stocks becomes optimal if either their target weight is low or intermediate consumption is substantial.     

The Risk-Return Relationship of Pension Funds With Investments in Hedge Funds

This article investigates if investing in local hedge funds improves the risk-return relationship of Brazilian pension funds. Investment in hedge funds by pension funds is growing elsewhere, with an increasing utilization of a multiplicity of hedge funds specialized in specific strategies or niches. We analyzed the performance of a typical pension fund allocation in Brazil as well as alternate allocations that included hedge funds. We used robust estimates of the covariance matrix to mitigate the errors in variables that are problematic in the inputs of the optimization. The results show that hedge funds improve the risk-return relationship of the typical pension fund allocation, contribute to a higher accumulated return at the end of a one-year period, and reduce portfolio rebalancing. Investments in hedge funds ease reaching the typical 6% annual return target with less risk exposure.     

Book Reviews

In a world of limited resources, marketing managers tasked to deliver shareholder value face decisions about how to maximise the returns on their marketing portfolio. Risk is less often considered. In finance the picture is very different; financial portfolio management is concerned with both risk and returns. The central innovation in this paper is the application of modern portfolio theory (MPT) to the management of marketing portfolios in food retailing and in drinks manufacturing. The authors develop a model that calculates an efficient frontier of marketing portfolios that maximise overall return within certain risk constraints, first for a simple two-segment marketing world and then for a more realistic multi-segment portfolio. However, marketing portfolios differ from financial ones in the sense that the allocation of marketing spend affects the returns from the portfolio. Therefore, a second innovation, an extension of MPT to take account of marketing spend allocation decisions, has been developed. Using this model, marketers can determine the risk and the returns of marketing investments, helping them select an optimal portfolio. This would go some way to ensuring that marketing contributes to shareholder value creation, currently one of its major challenges.     

THE NUMÉRAIRE PROPERTY AND LONG‐TERM GROWTH OPTIMALITY FOR DRAWDOWN‐CONSTRAINED INVESTMENTS

We consider the portfolio choice problem for a long‐run investor in a general continuous semimartingale model. We combine the decision criterion of pathwise growth optimality with a flexible specification of attitude toward risk, encoded by a linear drawdown constraint imposed on admissible wealth processes. We define the constrained numéraire property through the notion of expected relative return and prove that drawdown‐constrained numéraire portfolio exists and is unique, but may depend on the investment horizon. However, when sampled at the times of its maximum and asymptotically as the time‐horizon becomes distant, the drawdown‐constrained numéraire portfolio is given explicitly through a model‐independent transformation of the unconstrained numéraire portfolio. The asymptotically growth‐optimal strategy is obtained as limit of numéraire strategies on finite horizons.     

The optimal composition of foreign exchange reserves

This paper presents a model for selecting an optimal foreign exchange reserves portfolio for semi-industrial and developing countries, using the mean—approach. The model described here focuses on the relationship between the composition of reserves and that of imports, as well as the impact of return and risk of the investments in each currency. The empirical importance of these factors is demonstrated by investigating the optimal policy for Israel in the period 1972–1976. In comparing the actual and the efficient portfolio of different groups of countries, we find that profit considerations play a greater role in semi-industrial and developing countries than in industrial ones.     

Cross‐commodity analysis and applications to risk management

The understanding of joint asset return distributions is an important ingredient for managing risks of portfolios. Although this is a well‐discussed issue in fixed income and equity markets, it is a challenge for energy commodities. In this study we are concerned with describing the joint return distribution of energy‐related commodities futures, namely power, oil, gas, coal, and carbon. The objective of the study is threefold. First, we conduct a careful analysis of empirical returns and show how the class of multivariate generalized hyperbolic distributions performs in this context. Second, we present how risk measures can be computed for commodity portfolios based on generalized hyperbolic assumptions. And finally, we discuss the implications of our findings for risk management analyzing the exposure of power plants, which represent typical energy portfolios. Our main findings are that risk estimates based on a normal distribution in the context of energy commodities can be statistically improved using generalized hyperbolic distributions. Those distributions are flexible enough to incorporate many characteristics of commodity returns and yield more accurate risk estimates. Our analysis of the market suggests that carbon allowances can be a helpful tool for controlling the risk exposure of a typical energy portfolio representing a power plant. © 2009 Wiley Periodicals, Inc. Jrl Fut Mark 29:197–217, 2009     

Performance Analysis of Sustainable Investments in the Brazilian Stock Market: A Study About the Corporate Sustainability Index (ISE)

In this article, we studied the Corporate Sustainability Index (ISE) of the Brazilian Mercantile, Futures and Stock Exchange (BM&FBOVESPA), with the main objective of analyzing the performance of sustainable investments in the Brazilian stock market, during the period from December 2005 to December 2010. To achieve this aim, we characterized ISE portfolios and we compared its performance with the IBOVESPA (representing the market portfolio) and other BM&FBOVESPA sectoral indices. In the performance comparison, we used level of liquidity, return and risk indicators, as well as the following measures: Sharpe, Treynor, Sortino, and Omega. Our results show that although sustainable investments have presented some interesting characteristics, such as increasing liquidity and low diversifiable risk, they did not achieve satisfactory financial performance in the analysis period. This indicates that the constraints imposed by this type of investment in capital allocation in Brazil may be harming their return and risk attractiveness.     

Risk Perception in the Short Run and in the Long Run

There is an ongoing controversy in financial economics regarding the role of time horizon in portfolio selection. This problem is relevant in a broader context, wherever consumers or managers make decisions that involve both time and risk. The purpose of this paper is to review recent findings from the decision making literature so as to shed new light on how the short run vs. long run contingency may determine risk taking and perception.     

Do futures‐based strategies enhance dynamic portfolio insurance?

In this paper we investigate the relative performance of two approaches to dynamic portfolio insurance: the synthetic put and the Constant Proportion Portfolio Insurance (CPPI). The investigation is conducted on the Australian market, over a sample period of 59 non‐overlapping quarters from December 1987 to December 2002. Its main contribution is to provide a comprehensive assessment of the two approaches under different market conditions, and the testing of ex ante information as an input into the trading program. The major finding is that the futures‐based implementation of both synthetic put and the CPPI approach is robust to both tranquil and turbulent market conditions in preserving the desired floor. The fact that this conclusion includes the case of employing implied volatility (obtained from the options market) is highly encouraging as it suggests high implementability of the strategy. Notably, the risk‐return tradeoff shows that portfolio insurance using this volatility measure yields a return that is 64 basis points over the risk free investment. © 2004 Wiley Periodicals, Inc. Jrl Fut Mark 24:591–608, 2004     

Risk and Return in the 20th and 21st Centuries

The single most important contemporary issue in finance is the equity risk premium. This drives future equity returns, and is the key determinant of the cost of capital. The risk premium – the expected reward for bearing the risk of investing in equities, rather than in low-risk investments such as bills or bonds – is usually estimated from historical data. This article starts by summarising new evidence on historical returns in twelve major world markets from the authors' recent book, 'The Millennium Book: A Century of Investment Returns'. The authors show that the historical equity risk premium has been lower than previously believed, and argue that the future risk premium is likely to be lower still. They discuss what this implies for the cost of capital, stock market values, and companies' target rates of return. They suggest that many companies are seeking too high a rate of return and thus run the risk of under-investing.     

Country selection of emerging equity markets: benefits from country attribute diversification

We propose a multivariate scoring model based on four classes of variables to predict future returns of 23 emerging equity markets. For the periods 1986–1995 and 1996–2003, our long–short portfolio (11 top/bottom ranked countries) posts a quarterly significant average raw return and a quarterly significant average market risk-adjusted return. The all-classes model dominates the one-class-models. Results from this strategy are robust regardless of whether we concentrate on the 6 top/bottom countries, reduce the emerging market universe to the largest countries, eliminate the most rewarding country during the period, use different scores, or account for realistic implementation costs.     

Robust estimation of the optimal hedge ratio

When using derivative instruments such as futures to hedge a portfolio of risky assets, the primary objective is to estimate the optimal hedge ratio (OHR). When agents have mean‐variance utility and the futures price follows a martingale, the OHR is equivalent to the minimum variance hedge ratio,which can be estimated by regressing the spot market return on the futures market return using ordinary least squares. To accommodate time‐varying volatility in asset returns, estimators based on rolling windows, GARCH, or EWMA models are commonly employed. However, all of these approaches are based on the sample variance and covariance estimators of returns, which, while consistent irrespective of the underlying distribution of the data, are not in general efficient. In particular, when the distribution of the data is leptokurtic, as is commonly found for short horizon asset returns, these estimators will attach too much weight to extreme observations. This article proposes an alternative to the standard approach to the estimation of the OHR that is robust to the leptokurtosis of returns. We use the robust OHR to construct a dynamic hedging strategy for daily returns on the FTSE100 index using index futures. We estimate the robust OHR using both the rolling window approach and the EWMA approach, and compare our results to those based on the standard rolling window and EWMA estimators. It is shown that the robust OHR yields a hedged portfolio variance that is marginally lower than that based on the standard estimator. Moreover, the variance of the robust OHR is as much as 70% lower than the variance of the standard OHR, substantially reducing the transaction costs that are associated with dynamic hedging strategies. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:799–816, 2003     

Is it worth it? The rates of return from informal venture capital investments

Despite growing interest in venture capital, there is a paucity of information on the rate of return to these investments and the limited research that is available refers almost entirely to portfolio returns for venture capital funds. The investment returns to business angels have been virtually ignored. This paper provides the first attempt to analyse the returns to informal venture capital investment using data on 128 exited investments from a survey of 127 business angel investors in the UK. The paper finds that the distribution of returns is highly skewed, with 34% of exits at a total loss, 13% at a partial loss or break-even, but with 23% showing an IRR of 50% or above. Trade sales are the main way in which business angels harvest their investments. The median time to exit for successful investments was 4 years. Large investments, large deal sizes involving multiple coinvestors, and management buyouts (MBOs) were most likely to be high-performing investments.     

An Exact Test of the Improvement of the Minimum Variance Portfolio

I propose an exact finite sample test of the risk reduction of the global minimum variance (GMV) portfolio. The GMV test statistic is proportional to the reduction in the variance of the GMV portfolio and has a straightforward geometric and portfolio interpretation and complements the celebrated GRS test in Gibbons et al. (1989). In practical applications, the GMV test leads to a rejection of the null hypothesis of no improvement in the GMV portfolio more often than the GRS test rejects the null hypothesis of no improvement in the risk‐return profile of the tangent portfolio. The power of the GMV test increases with the variance reduction of the GMV portfolio. Using test asset returns scaled by predetermined predictive variables is equivalent to increasing the overall number of test assets and leads to substantial power gains.     

The conditional relationship between beta and returns: recent evidence from international stock markets

The risk–return relationship is one of the fundamental concepts in finance that is most important to investors and portfolio managers. Finance theory argues that the beta or systematic risk is the only relevant risk measure for investors. However, many studies have showed that betas and returns are not related empirically, no matter in domestic markets or in international stock markets. This paper examines the conditional relationship between beta and returns in international stock markets for the period from January 1991 to December 2000. After recognizing the fact that while expected returns are always positive, realized returns could be positive or negative, we find a significant positive relationship between beta and returns in up market periods (positive market excess returns) but a significant negative relationship in down market periods (negative market excess returns). The results are robust for both monthly and weekly returns and for two different proxies of the world market portfolio. Our findings indicate that beta is still a useful risk measure for portfolio managers in making optimal investment decisions.     

城市经济转型时期人力资本回报率研究

基于Mincer基本模型和扩展模型的估算结果显示 ,中国城市地区的教育回报率比其他发展中国家的平均水平低 ,但这一回报率在不断上升 ;职工工资收入达到最高水平所需工作的年限在下降 ,工作年限的边际回报率在下降 ,尤其是女性工作年限的边际回报率下降速度更快。在 1986 /1987年 ,广东城市职工平均工资收入比湖南和四川高出 30 % ,而在 1993/1994年 ,广东城市职工平均工资收入比湖南和四川高出 70 % ,表明地区收入不平等的现象在扩大。令人费解的是 ,广东省的教育回报率并不高 ,尽管在这期间广东省男女两性的工作经验回报率大大下降。文章还发现 ,无论是工资性别歧视 ,还是职业性别歧视都似乎存在于中国城市的劳动力市场中     

Family Composition and Investment in Household Capital: Contrasts in the Behavior of the Husband-Wife and Female-Headed Households

This paper estimates a portfolio model that includes investment in human capital, as well as traditional investments of housing, financial assets, and automobiles, and that contrasts portfolios of husband-wife households with female-headed households. Female headed households adjust their portfolios to disequilibria in various stocks more slowly than husband-wife households.     

Retail investors and financial advisors: New evidence on trust and advice taking heuristics

This paper investigates factors that influence trust and advice taking among retail investors when consulting with financial advisors and making real-world portfolio decisions. The data reveal that non-expert retail investors trust their advisors a lot. Trust formation appears to be well described by a simple heuristic that relies substantially on the advisor's communication style when deciding how much to trust and delegate investment decisions. Portfolio decisions appear to depend more on investors' perceptions about the investor–advisor relationship than on the risk and return characteristics of investments comprising the portfolio choice set. This evidence supports Pentland's (2008) “honest signals” as a more powerful mechanism underlying investor trust than standard metrics based on past performance. Trust and advice-taking heuristics can be interpreted as well adapted to the environment of the non-profit bank cooperatives in which they are observed, implying that trusting based on simple honest signals, although vulnerable to exploitation, can be interpreted as ecologically rational. Features of the investor's environment typical of non-profit cooperative banks imply that the heuristics investors use can perform rather well without requiring investment experience or financial sophistication, which most investors in our sample are well aware they lack.