The effectiveness of the VaR-based portfolio insurance strategy: An empirical analysis

This paper proposes an approach to constructing the insured portfolios under the VaR-based portfolio insurance strategy (VBPI) and provides a comprehensive analysis of its hedging effectiveness in comparison with the buy-and-hold (B&H) as well as the constant proportion portfolio insurance (CPPI) strategies in the context of the Chinese market. The results show that both of the insurance strategies are able to limit the downward returns while retaining certain upside returns, and their capabilities of reshaping the return distributions increase as the guarantee or the confidence level rises. In general, the VBPI strategy tends to outperform the CPPI strategy in terms of both the degree of downside protection and the return performance.     

The role of correlation dynamics in sector allocation

This paper assesses the economic value of modeling conditional correlations for mean–variance portfolio optimization. Using sector returns in three major markets we show that the predictability of models describing empirical regularities in correlations such as time-variation, asymmetry and structural breaks leads to significant performance gains over the static covariance strategy. Investors would be willing to pay a fee of up to 983 basis points to switch from the static to the dynamic correlation portfolio and about 100 basis points more for capturing asymmetries and shifts in correlations. The gains are robust to the crisis, transaction costs and are most pronounced for monthly rebalancing.     

Portfolio Insurance with Liquidity Risk

This paper studies a portfolio insurance problem with liquidity risk. We consider an investor who wants to maximize the expected growth rate of wealth in a low liquid market. The investor can trade assets only at random times and his wealth must not fall below a predetermined floor. We find the optimal expected growth rate and an optimal strategy. The optimal strategy is closely related with a traditional constant proportion portfolio insurance strategy. Also we show that the same strategy maximizes the growth rate almost surely. Further we study the floor effect on the growth rate.     

Trading frenzies and their impact on real investment

We study a model in which a capital provider learns from the price of a firm's security in deciding how much capital to provide for new investment. This feedback effect from the financial market to the investment decision gives rise to trading frenzies, in which speculators all wish to trade like others, generating large pressure on prices. Coordination among speculators is sometimes desirable for price informativeness and investment efficiency, but speculators' incentives push in the opposite direction, so that they coordinate exactly when it is undesirable. We analyze the effect of various market parameters on the likelihood of trading frenzies to arise.     

The impact of global economic policy uncertainty on portfolio optimization: A Black–Litterman approach

This paper investigates the asymmetric impact of global economic policy uncertainty (GEPU) on global asset allocation. We employ the Double Asymmetric GARCH-MIDAS (DAGM) model to examine the asymmetric effect of GEPU shocks on long-term volatilities of global equities, bonds, commodities, clean energy and Bitcoin. The GEPU-based volatility is used as a proxy for the uncertainty of the investor’s views in the Black-Litterman (BL) framework. Empirical results show that the BL model with GEPU-based views yields higher out-of-sample risk-adjusted returns than other traditional benchmarks in most cases. The findings suggest that investors should consider the influence of GEPU when making portfolio decisions.     

Greenpeace v. Shell: media exploitation and the Social Amplification of Risk Framework (SARF)

This paper examines the usefulness of the Social Amplification of Risk Framework (SARF) in understanding the media's role in risk communication. Since the SARF was created in 1988, it has been both further developed and critiqued for (amongst other things) its: static conception of communication; lack of attention towards how key actors use the media; lack of systematic attention towards the media as an amplification station; and simplistic assumptions of how the media operate as an amplification station. A complex heavily‐mediated risk communication case study—the battle between Greenpeace and Shell over the deep‐sea disposal of the Brent Spar oil rig (1995)—is used to explore whether the SARF in its current stage of development stands up to these critiques. It is concluded that these critiques are more a consequence of how researchers have used the SARF rather than a fault of the SARF itself. Using the SARF framework with a qualitative case study methodology enabled systematic analysis of the role of relevant media in the social amplification of risk in the Spar issue, exposing how Greenpeace used the media to successfully communicate three risk signals, together with the inadequacies of Shell's reactions; and revealing the layering within amplification stations, including the media itself.     

Deep hedging

We present a framework for hedging a portfolio of derivatives in the presence of market frictions such as transaction costs, liquidity constraints or risk limits using modern deep reinforcement machine learning methods. We discuss how standard reinforcement learning methods can be applied to non-linear reward structures, i.e. in our case convex risk measures. As a general contribution to the use of deep learning for stochastic processes, we also show in Section 4 that the set of constrained trading strategies used by our algorithm is large enough to ε-approximate any optimal solution. Our algorithm can be implemented efficiently even in high-dimensional situations using modern machine learning tools. Its structure does not depend on specific market dynamics, and generalizes across hedging instruments including the use of liquid derivatives. Its computational performance is largely invariant in the size of the portfolio as it depends mainly on the number of hedging instruments available. We illustrate our approach by an experiment on the S&P500 index and by showing the effect on hedging under transaction costs in a synthetic market driven by the Heston model, where we outperform the standard ‘complete-market’ solution.     

Hedge fund return,volatility asymmetry,and systemic effects: A higher-moment factor-EGARCH model

We investigate whether: (i) co-skewness and co-kurtosis are significant factors in modeling hedge fund (HF) returns, (ii) HF return volatility displays clusters, asymmetry and shock persistence, (iii) volatility clusters of HF styles drive volatility clusters of one another, major asset classes, and major banking organizations, (iv) HF return and volatility patterns changed after the financial crises of 1998 and 2007–2009. A higher-moment EGARCH model and monthly data over January 1993–April 2014 period on 13 HF styles are employed. Out-of-sample forecasts are generated over the period of May 2014–April 2016. Results show: (i) most of the co-skewness and co-kurtosis coefficients are statistically significant, strongly supporting the higher-moment return generating models; (ii) there is strong evidence in favor of EGARCH specification, volatility clustering, asymmetry, and shock persistence; (iii) there were distinct effects on the returns and volatilities of HFs during the 1998 Russian bond crisis, Long-Term Capital Management crisis, and the 2007–2009 financial crisis; and (iv) shocks to volatility clusters of a HF style do spillover to other HF styles, major banking firms, and key asset classes. Our findings have major implications for regulators, investors, HF managers and hedging strategists.     

‘Real without being concrete’: the ontology of public concern and its significance for the Social Amplification of Risk Framework (SARF)

Abstract

Public concern is a pivotal notion in the risk perception, communication and management literature. It is, for example, a central concept with regard to the social amplification of risk, and as a justification for policy attention. Despite its ubiquity, the notion of public concern remains a ‘black box’ presenting a poorly understood state of affairs as a reified matter-of-fact. Paying attention to the deployment and metrics of public concern, and the work it is required to do, will enhance the power of approaches to understanding risk, and policymaking. Thus, the broad purpose of this paper is to unpack the notion of public concern by adopting an ontological yet critical perspective, drawing on a range of literature that considers ontology. We reflect on how publics and public concern have been conceptualised with regard to the dichotomies of individual/social and private/public, given that they imply different levels and dimensions of concern. We draw on empirical work that illuminates the assessment and measurement of public concern and how the public have responded to risk events. Considering public concern through an ontological lens affords a means of drawing renewed critical attention to objects that might otherwise appear finished or ready-made.     

Dynamic spillover effects among green bond,renewable energy stocks and carbon markets during COVID-19 pandemic: Implications for hedging and investments strategies

This study has been inspired by the emergence of socially responsible investment practices in mainstream investment activity as it examines the transmission of return patterns between green bonds, carbon prices, and renewable energy stocks, using daily data spanning from 4th January 2015 to 22nd September 2020. In this study, our dataset comprises the price indices of S&P Green Bond, Solactive Global Solar, Solactive Global Wind, S&P Global Clean Energy and Carbon. We employ the TVP-VAR approach to investigate the return spillovers and connectedness, and various portfolio techniques including minimum variance portfolio, minimum correlation portfolio and the recently developed minimum connectedness portfolio to test portfolio performance. Additionally, a LASSO dynamic connectedness model is used for robustness purposes. The empirical results from the TVP-VAR indicate that the dynamic total connectedness across the assets is heterogeneous over time and economic event dependent. Moreover, our findings suggest that clean energy dominates all other markets and is seen to be the main net transmitter of shocks in the entire network with Green Bonds and Solactive Global Wind, emerging to be the major recipients of shocks in the system. Based on the hedging effectiveness, we show that bivariate and multivariate portfolios significantly reduce the risk of investing in a single asset except for Green Bonds. Finally, the minimum connectedness portfolio reaches the highest Sharpe ratio implying that information concerning the return transmission process is helpful for portfolio creation. The same pattern has been observed during the COVID-19 pandemic period.     

我国锌期货市场功能发挥的实证研究

运用协整检验、Granger因果检验、向最误差修正模型、Garhade-silber模型、误差修正模型等对2007年6月11日到2008年9月18日上海期货交易所锌期货合约的价格发现功能和套期保值功能进行研究,结果表明:锌期货与现货价格存在双向引导关系,锌期货市场在价格发现功能中处于主导地位,锌期货价格发现功能良好.锌期货样本内和样本外套期保值绩效分别为0.50074044和0.43854111,样本内套期保值绩效优于样本外套期保值绩效.我国锌期货市场具有一定的套期保值功能,但套期保值功能并未得到充分发挥,2008年6月到2008年9月锌期货市场投机氛围严重.     

农业保险对财政投入的放大效应分析

相比直接的灾后财政救济,利用政策性农业保险机制能实现对财政投入效果的放大。本文在对中国和其他实施农业保险国家的对比中总结出对农业保险财政投入的范围、形式,重点剖析了利用农业保险实现财政投入放大效应的作用机制,提出了衡量这一效应的方法和指标,并据此对我国主要农险经营模式的实际放大效果及其原因进行了比较分析,最后,本文针对...     

Explaining asset pricing puzzles associated with the 1987 market crash

The 1987 market crash was associated with a dramatic and permanent steepening of the implied volatility curve for equity index options, despite minimal changes in aggregate consumption. We explain these events within a general equilibrium framework in which expected endowment growth and economic uncertainty are subject to rare jumps. The arrival of a jump triggers the updating of agents' beliefs about the likelihood of future jumps, which produces a market crash and a permanent shift in option prices. Consumption and dividends remain smooth, and the model is consistent with salient features of individual stock options, equity returns, and interest rates.     

Changes in volatility of credit spread and market efficiency during rapid growth of credit-related securities

This paper investigates the changes in credit spread volatility during 1993–2001. We find that the credit spreads between junk-grade corporate bonds and Treasury bonds were significantly more volatile in the second half of this period when credit-related securities became popular. In contrast, investment-grade bonds exhibited no significant change in volatility. The junk bonds variance ratios changed from being less than one to greater than one. Using the GJR-Garch model, the conditional volatilities of junk bonds increased in the second half of the period and the mean reversion speeds slowed, suggesting a longer time for mean reversion to occur. Our analysis rules out treasury volatility, credit spread level, equity market return, T-bill rate, curvature of the Treasury curve, financial crisis, quantity of defaults and standard deviation of defaults as explanations for the increase in junk bond volatility. In contrast, volatility of equity returns provides a partial explanation of junk bond spread volatility in the later period.     

DCC-GARCH、M-Copula-GARCH和Copula-SV在商品期货对冲中的应用研究

中国商品期货市场已经成为全球期货市场不可或缺的重要组成部分。文章比较研究了DCC-GARCH、M-Copula-GARCH和Copula-SV三种模型对我国最重要的期货合约——铜和棉花的对冲比率的影响。结果表明:Copula-SV是最优的对冲模型,文章还发现:二月期的铜期货合约和三月期的棉花期货合约对冲现货的效率最高。     

Hedging, hedge accounting, and speculation in a rational expectations equilibrium

This paper explains corporate hedging and speculation in a two period rational expectations model. A risk averse manager represents a firm that is priced in a risk neutral market. The manager enters into a cash flow hedge of a forecast transaction by taking a short position in the futures market. When the futures position is chosen, the manager possesses private information regarding the firm’s production capacity. Mandatory disclosure of the futures position in the financial statements allows the market to draw inferences over the manager’s information. These inferences affect the market’s pricing decision and in turn the manager’s hedging decision. The futures position taken is chosen not only to reduce price risk exposure but to signal some capacity level. In equilibrium, however, the market anticipates the manager’s strategy and is not fooled.Considering varying managerial preferences, we analyze three settings. In the basic setting speculation occurs whenever the manager prefers high market values in both periods. In the second setting we add transaction costs and find that speculation is less likely. Finally, we introduce uncertainty regarding the manager’s preferences. If the market needs to determine prices based on expected preferences, incentives to speculate are mitigated in equilibrium but still present.     

对金融工程及其发展的思考

金融工程的实质是金融领域的创新与创造 ,包括创新金融工具与金融手段的设计、开发与实施。金融工程提供了一种新的思维方式和金融创新技术 ,金融工程活动和金融工程教育在国外得到飞速发展 ,成为近 2 0年来现代金融发展的重要推动力 ,并且代表着金融发展的方向。在我国开展有关金融工程的研究和教育 ,树立金融工程意识 ,具有重要的现实意义和广阔的发展前景。     

Decomposing mutual fund alpha into security selection and security weighting

I decompose mutual fund alpha into two components: which stocks a mutual fund selects and what weights are placed in those stocks. Although related, each decision has a distinguishable impact on portfolio alpha. I show that deciding how to weight securities is of greater importance than deciding which securities to select. The ability to generate weighting alpha persisting for 12 months while the ability to generate selecting alpha persists for just one. Finally, the performance of mutual funds that both accurately weight and select securities persists for one month and results in significant outperformance.     

基于牛市和熊市不同周期的股票市场动量效应研究

在参考国外研究方法的基础上,以周作为检验周期,将1997年6月至2001年6月的股市作为牛市,2001年6月至2005年6月的股市作为熊市,然后分别检验股市在这两个不同时期的动量效应.研究发现,赢家组合在牛市中存在着正的动量效应,输家组合在熊市中存在着负的动量效应.而牛市中的输家组合和熊市中的赢家组合都存在着价格的反转.