Risk

  • 详情 Market Crowd's Trading Behaviors, Agreement Prices, and the Implications of Trading Volume (市场群体的交易行为、认同价格以及交易量的内涵)
    It has been long that literature in financial academics focuses mainly on price and return but much less on trading volume. In the past twenty years, it has already linked both price and trading volume to economic fundamentals, and explored the behavioral implications of trading volume such as investor’s attitude toward risks, overconfidence, disagreement, and attention etc. However, what is surprising is how little we really know about trading volume. Here we show that trading volume probability represents the frequency of market crowd’s trading action in terms of behavior analysis, and test two crowd’s trading behavioral hypotheses relevant to the volume uncertainty associated with price in China stock market. The empirical work reveals that market crowd trade in simple heuristics and efficient adaptation, gradually tend to achieve agreement on an outcome or an asset price widely on a trading day, and generate such a stationary equilibrium price very often in interaction among themselves no matter whether it is highly overestimated or underestimated, suggesting that asset prices include not only a fundamental value but also private information, speculative, sentiment, gamble, and entertainment values etc. In addition, market crowd adapt to gain and loss by trading volume increase or decrease significantly in interaction with environment in any two consecutive trading days. Our results demonstrate how interaction between information and news, the trading action, and return outcomes in the three-term feedback loop produces excessive trading volume which includes various internal and external causes. Finally, we reconcile market dynamics and crowd’s trading behaviors in a unified framework by Shi’s price-volume differential equation in stock market where, we assume, investors derive a liquidity utility expressed in terms of trading wealth which is equal to the sum of a probability weighting utility and a reversal utility in reference to an outcome. JEL Classifications: G12, G02, D83 (长期以来,金融学术领域里的文献只注重价格和收益率,却较少研究交易量。在最近的二十年里,金融学术文献已经开始研究价格和交易量两者与经济基本量之间的相互关系,并且探讨交易量的行为内涵,例如投资者对风险的态度、过度自信、不同观点以及关注程度等等。然而,我们还是对交易量的认识知之甚少。本文根据行为分析,用交易量概率来表示市场群体的交易频率,并且通过我国股市来实证检验交易量与价格之间不确定关系中关于群体交易行为的两个基本假说。实证结果表明:市场群体在每日交易的时间窗口内采用简单的经验法则和有效的适应方式来从事交易,并且总是逐步地倾向于形成一个结果和认同的资产价格;无论该资产价格是否明显地被高估或低估,市场群体在相互作用的过程中往往能够形成这样一个稳态的均衡价格,这表明了资产价格不仅包含基本价值同时还包含非公开信息、投机、情绪、赌博和娱乐等价值。此外,在任意两个连续交易日之间,市场群体在与市场环境的相互作用过程中,通过交易量的增加或减少来有效地适应盈亏。我们的研究结果说明了在由信息、交易与收益结果三项构成的反馈环中,它们之间的相互作用是如何导致了过度交易的,这其中包含了导致过度交易的各种内外因素。最后,我们假设股票市场中的投资者是通过交易财富来产生流动性效用,它等于概率加权效用与相对于结果为参照系的反转效用之和,从而推导出Shi氏价-量微分方程,将市场动力学行为与群体交易行为协调在一个统一的框架体系。)
  • 详情 Ultimate ownership, bank connections and collateral in China
    Using a sample of China’s listed private firms we investigate the relationship between control-ownership wedge, bank connections and collateral requirement. We find that while control-ownership wedge relates to more pledged collateral, it is mainly the firm’s bank connections rather than its political connections that reduce the collateral requirement and weakens the positive relationship between the control-ownership wedge and collateral. We furhter find that the split-share structure reform and regions with high lender competition also require less collateral and weaken the positive relationship between the control-ownership wedge and collateral. We argue that in an emerging market where legal protection for creditors and investors are weak and relationship is prevalent, bank connections is a substitute for collateral through mitigating the information asymmetry and agency concerns by creditors, which has been further exacerbated due to the tunnelling risk by the controlling shareholders.
  • 详情 商业银行流动性风险监管的流变及在中国的实践
    本文针对商业银行流动性风险国际监管框架的演变,探讨监管重点与流动性风险变化的互动关系,从而梳理出国际流动性风险监管的目的、手段和发展趋势,进而研究其对我国流动性风险监管实践的影响。 本文从分析商业银行流动性风险的成因入手,指出其根源是银行存款和贷款业务所形成的期限错配,因此这种风险是银行在经营活动中难以避免的。流动性风险区别于银行面临的其他风险的主要表现是其低频率、高损失的特点,这使得银行一旦面临流动性危机的打击就很难在短时间内恢复过来,所以必须引起银行管理层和监管机构的重视。从20世纪90年代起单一的流动性指标监管方法已经逐渐被综合的流动性风险管理体系所取代,但各国之间尚存在较大差异。 本文对次贷危机前美国、英国和东亚各国的流动性风险监管框架作了横向比较。经过比较后发现,在流动性风险监管体系中,存在两种不同的方法,即定性方法和定量方法。前者偏重在制度层面对银行进行指导以提高其流动性风险管理能力,而后者则偏重以硬性指标客观计量和评估流动性风险,两者互有优劣,不可偏废。相对来说,英美国家因为金融制度比较完善、人才水平较高,其监管机构以使用定性方法为主;而东亚各国由于金融发展水平较低,产品结构简单,从业人员水平参差不齐,所以更偏好使用定量方法。 当各国金融监管机构还在为如何在定性方法和定量方法之间进行取舍的时候,美国次贷危机和之后席卷全球的金融危机不期而至,这大大加快了流动性风险管理理念和监管实践的发展速度。作为次贷危机的受害者,本文深入分析了英国北岩银行(Northern Rock plc)的挤兑危机案例,对危机背景、银行的经营特点、事件经过和后续影响都作了较为细致的论述,并指出银行自身流动性风险管理不善是形成危机的主要原因,这表现在不合理的资产负债结构、期限错配、利率缺口以及内部控制的缺失。尽管北岩银行管理层对于流动性危机的发生负有不可推卸的责任,但是监管失败的教训同样发人深省,这间接促成了巴塞尔银行监管委员会(Basel Committee on Banking Supervision,以下简称巴塞尔委员会)制定后危机时代的流动性风险监督管理新框架。 本文回顾了历年巴塞尔委员会制定的流动性风险监管文件,将其大致分为次贷危机前和次贷危机后两大类。本文指出,巴塞尔委员会早期制定的流动性监管框架已经很难适应飞速发展的国际金融形势,面临诸多迫切需要解决的问题,包括融资渠道的变化、资产证券化、复杂金融工具的泛滥、抵押品的广泛应用、支付结算系统和日内流动性需求以及跨境资金流。在这些问题中,很大部分也同样存在于危机前的北岩银行,因此危机的爆发带有某种必然性。巴塞尔委员会在次贷危机后发布的《流动性风险管理和监督稳健原则》和《第三版巴塞尔协议:流动性风险计量、标准和监测的国际框架》奠定了第三版巴塞尔协议下国际流动性风险监管新框架的基石。前者制定的17项流动性风险监管新原则和后者引入的流动性覆盖率(Liquidity Coverage Ratio,简称LCR)和净稳定资金比例(Net Stable Funding Ratio,简称NSFR)两大指标分别从定性方法和定量方法两方面完善了现有的流动性风险监管框架,这也反映了未来国际流动性风险监管的趋势。 正如在本文开篇提到的,流动性风险是银行不可避免的风险,对于中国银行业来说,也不能置身事外。经过分析我国银行业的流动性风险现状,笔者认为我国银行的资产负债结构仍属传统,偏重以存款作为融资来源、以贷款作为盈利来源,因此长期流动性风险不容忽视而短期流动性风险尚属可控。同时,不同类型商业银行的流动性风险来源也有所不同。此外,国内银行的流动性风险管理水平也有待提高。与巴塞尔协议类似,在次贷危机前后,我国的流动性风险监管框架也有了质的飞跃,这主要归功于中国银监会颁布的《中国银行业实施新监管标准的指导意见》、《商业银行流动性风险管理指引》和《商业银行流动性风险管理办法(试行)》(征求意见稿)。这些法规系统性地借鉴巴塞尔委员会的先进经验,辅以本地化的监测工具,从而形成了兼顾定性方法和定量方法的有中国特色的流动性风险监督管理新框架。 本文最后指出,无论是定性方法还是定量方法,在流动性风险监管中都起着举足轻重的作用,两者不可偏废。监管机构在设计流动性风险监管框架并实施现场或非现场监管时,应灵活运用定性方法和定量方法并结合压力情景评估银行的流动性风险,这样才能全面有效地实施流动性风险监管,避免系统性的流动性危机。另外,本文还建议我国监管机构在本地化国际流动性风险监管框架方面做更多尝试。 With respect to the evolution of the international supervision framework for commercial bank’s liquidity risk, this article aims to discuss the interaction between the regulatory focuses and the diversification of liquidity risk, in order to sort out the purposes, approaches and development trends of the international supervision on liquidity risk and their impacts on China’s supervision practice of liquidity risk. In regard to the causes of commercial bank’s liquidity risk, this article points out that the mismatch of maturity between the bank’s deposits and loans is the fundamental reason. Such risk is inevitable when conducting banking business. The features of liquidity risk (i.e. low frequency but extremely severe) distinguish itself from other risks that the bank faces, which hinders the bank from a quick recovery after being stricken by a liquidity crisis. Therefore, both the bank management and the regulators must draw their attentions to it. From 1990s, the monitoring method of single indicator has been gradually replaced with the comprehensive liquidity risk management system. However, there are still big variances between different countries. This article compares the framework for liquidity risk supervision between the United States, the United Kingdom and the East Asian countries prior to the subprime mortgage crisis. It is noted after comparison that there are two different approaches in the liquidity risk supervision system, namely the qualitative approach and the quantitative approach. The former emphasizes improving the bank’s liquidity risk management skill by guiding the bank from governance perspective, while the latter prefers measuring and evaluating the liquidity risk by means of objective indicators. Each of these two approaches has its pros and cons that neither should be overemphasized at the expense of the other. Relatively speaking, the Anglo-American countries prefer qualitative approaches due to their mature financial system as well as professional practitioners. By contrast, East Asian countries rely on quantitative approach because of their under-developing financial system, simple product structure and less experienced practitioners. When the financial regulators in various countries were still wondering whether to adopt the qualitative approach or the quantitative approach, the subprime mortgage crisis occurred in the United States and thereafter became a global financial crisis. This crisis accelerated the development of the management theory and the supervision practice of liquidity risk. This article analyzes the bank run on Northern Rock plc (the Bank) in the United Kingdom, a victim of the subprime mortgage crisis, by elaborating the crisis background, the business features of the Bank, the incident course as well as the subsequent impacts. The major cause of the bank run was the Bank’s own mismanagement of its liquidity risk, which included unbalanced structure of assets and liabilities, maturity mismatch, interest rate gap and ineffective internal control as well. Although the management of the Bank bore the ultimate responsibility for this liquidity crisis, the lesson of the supervision failure was thought-provoking. It also indirectly led to the renewed framework for the post-crisis liquidity risk management and supervision by the Basel Committee on Banking Supervision (the Basel Committee). This article reviews the historical documents of liquidity risk supervision that were formulated by the Basel Committee and divides them into two categories, i.e. before and after the subprime mortgage crisis. This article points out that the framework for liquidity risk supervision which was established by the Basel Committee at the early stage could no longer meet the rapid development of the international financial environment and faced many problems which need be solved urgently. These problems included the change of financing channels, asset securitization, misapplication of complex financial instruments, extensive use of collaterals, payment-settlement system, demand for intraday liquidity and cross-border cash flow. Northern Rock plc had most of these problems prior to its bank run crisis. Therefore, the crisis was with certain inevitability. After the subprime mortgage crisis, the Basel Committee issued “Principles for Sound Liquidity Risk Management and Supervision” and “Basel III: International Framework for Liquidity Risk Measurement, Standards and Monitoring” which laid the foundation of the renewed international framework for the liquidity risk supervision under Basel III. The former defines 17 new principles of liquidity risk supervision whilst the latter introduces two key indicators, i.e. the Liquidity Coverage Ratio (LCR) and the Net Stable Funding Ratio (NSFR). Both of the two foundational documents improve the existing framework for liquidity risk supervision from qualitative and quantitative aspects respectively. They also reflect the trends of international liquidity risk supervision. As mentioned at the beginning of this article, the liquidity risk is inevitable to all banks including the China’s banks. Based on the analysis of the status quo of the Chinese banks’ liquidity risk, the author draws the conclusion that the structures of assets and liabilities of the China’s banks are traditional, i.e. the deposits are the source of financing while the loans are the source of profit. Hence, their long-term liquidity risk cannot be ignored whilst their short-term liquidity risk is still under control. In addition, the liquidity risk management skills of the China’s banks need further improvement. Similar to the Basel Accord, the China Banking Regulatory Commission (the CBRC) promulgated “Guidance Opinions on the Implementation of the New Supervisory Standards of Basel III in China Banking Sector”, “Guidelines on Liquidity Risk Management for Commercial Banks” and “Administrative Measures on Liquidity Risk Management for Commercial Banks (Trial) (Draft for Consultation)” right after the subprime mortgage crisis, which made great improvement in the framework for liquidity risk supervision in China. By referring to the advanced experiences of the Basel Committee, together with the help of the localized monitoring tools, these regulations forms a new framework for liquidity risk management and supervision with Chinese characteristics which takes into account both the qualitative and quantitative approaches. Finally, this article reminds that both the qualitative and quantitative approaches play equally important roles in the field of liquidity risk supervision that neither of them is dispensable. When designing the framework for liquidity risk supervision and conducting the on-site or off-site inspections, the regulators should apply flexibility in the use of qualitative and quantitative approaches and attach importance to the stress scenarios to assess the bank’s liquidity risk. By this means, comprehensive and effective supervision on liquidity risk can be achieved to prevent systemic liquidity crisis. Furthermore, it is suggested that the domestic regulators should make more efforts to localize the international framework for liquidity risk supervision.
  • 详情 Contingent capital with repeated interconversion between debt and equity
    We develop a new type of contingent capital, called contingent convertible security (CCS), which is like a contingent convertible bond (CCB) but differently can be interconverted \emph{repeatedly} and automatically between debt and equity depending on two specified levels of the cash flow generated by the firm that issues the CCS. We derive closed-form expressions of the equilibrium prices of corporate securities and optimal capital structure when the cash flow of the firm is modeled as geometric Brownian motion. Especially, we provide very simple formulas on optimal capital structure including a CCB. We show that the CCS can not only decrease default risk like a CCB, but also can significantly increase the firm's value. In particular, the CCS can be used to solve financing problems of small- and medium-sized enterprises as well as banks.
  • 详情 International Portfolio Selection with Exchange Rate Risk: A Behavioural Portfolio Theory Perspective
    This paper analyzes international portfolio selection with exchange rate risk based on behavioural portfolio theory (BPT). We characterize the conditions under which the BPT problem with a single foreign market has an optimal solution, and show that the optimal portfolio contains the traditional mean–variance efficient portfolio without consideration of exchange rate risk, and an uncorrelated component constructed to hedge against exchange rate risk. We illustrate that the optimal portfolio must be mean–variance efficient with exchange rate risk, while the same is not true from the perspective of local investors unless certain conditions are satisfied. We further establish that international portfolio selection in the BPT with multiple foreign markets consists of two sequential decisions. Investors first select the optimal BPT portfolio in each market, overlooking covariances among markets, and then allocate funds across markets according to a specific rule to achieve mean–variance efficiency or to minimize the loss in efficiency.
  • 详情 考虑机会成本的算法交易策略
    为了减少市场冲击成本,高频交易者通常会将大额指令拆分为小额指令择机逐次提交,但同时也存在指令不能全部成交的风险。针对现有文献主要考虑指令全部成交的不足,本文提出了一种估计交易策略机会成本的方法,在最小化总交易成本的目标下,分析了投资者同时考虑市场冲击成本和机会成本的情形与投资者同时考虑市场冲击成本、机会成本和择时风险情形下如何制定最优交易策略的问题。研究结论表明,如果投资者只考虑冲击成本,或者虽然也同时了考虑机会成本但若所有交易时期指令的成交概率都相等,那么投资者最优的算法交易策略仍然是采用著名的交易量加权平均价格(Volume Weighed Average Price,VWAP)交易策略;如果投资者同时考虑市场冲击成本和机会成本,且对于所有交易时期指令的成交概率不一致但交易者能预先预期总的可执行指令大小的特殊情况,本文得到了此问题解的解析解,对于各交易时期指令成交概率不一致的一般情形,通过数值示例发现,对于不同交易时期指令的成交概率分别为递增、递减和U型三种不同情形,投资者同时关注市场冲击成本和机会成本时最优指令提交策略(Market Impact and Opportunity Cost,MIOC)的总交易成本均小于VWAP交易策略;如果投资者同时考虑市场冲击成本、机会成本和择时风险,通过数值示例发现,对于各交易时期指令成交概率分别为递增、递减和U型的三种不同情形,投资者最优指令提交策略(Market Impact, Opportunity Cost and Timing Risk,MIOCTR)的总交易成本均小于MIOC交易策略和VWAP交易策略;
  • 详情 Against the tide: The commencement of short selling and margin trading in mainland China
    China?s recent removal of short selling and margin trading bans on selected stocks enables testing of the relative effect of margin trading and short selling. We find the prices of the shortable stocks decrease, on average, relative to peer A-shares and cross-listed H-shares, suggesting that short selling dominates margin trading effects. However, there is negligible short sales activity and contrary to the regulators? intention, and recent empirical evidence, liquidity declines and bid-ask spreads increase in these shortable stocks. Consistent with Ausubel (1990), together these results imply uninformed-investors avoid these stocks to reduce the risk of trading with informed-investors.
  • 详情 Convertibility Restriction in China’s Foreign Exchange Market and its Impact on Forward Pricing
    Different from the well established markets such as the dollar-Euro market, recent CIP deviations observed in the onshore dollar-RMB forward market were primarily caused by conversion restrictions in the spot market rather than changes in credit risk and/or liquidity constraint. This paper proposes a theoretical framework under which the Chinese authorities impose conversion restrictions in the spot market in an attempt to achieve capital flow balance, but face the tradeoff between achieving such balance and disturbing current account transactions. Consequently, the level of conversion restriction should increase with the amount of capital account transactions and decrease with the amount of current account transactions. Such conversion restriction in turn places a binding constraint on forward traders’ ability to cover their forward positions, resulting in the observed CIP deviation. More particularly, the model predicts that onshore forward rate is equal to a weighted average of CIP-implied forward rate and the market’s expectation of future spot rate, with the weight determined by the level of conversion restriction. As a secondary result, the model also implies that offshore non-deliverable forwards reflect the market’s expectation of future spot rate. Empirical results are consistent with these predictions.
  • 详情 Is warrant really a derivative? Evidence from the Chinese warrant market
    This paper first studies the Chinese warrant market that has been developing since August 2005. Empirical evidence shows that the market prices of warrants are much higher systematically than the Black-Scholes prices with historical volatility. The prices of a warrant and its underlying asset do not support the monotonicity, perfect correlation and option redundancy properties. The cumulated delta-hedged gains for almost all expired warrants are negative. The negative gains are mainly driven by the volatility risk, and the trading values of the warrants for puts and the market risk for calls. The investors are trading some other risks in addition to the underlying risk.
  • 详情 A study on Chinese Yuan index and its Derivatives
    Following the successful experience of USDX, this paper gives a profile of how to design a foreign exchange index for China and elaborates three functions and implications of CNYX in foreign exchange market. This paper also demonstrate the models to get the equilibrium price of CNYX derivatives. CNYX derivatives provide traders and hedgers with a tool for avoiding risk and give a new approach for China’s large foreign reserve to optimize its structure to prevent the devaluation.