我国证券市场效率不高的原因与治理对策

近十几年以来,我国证券市场发展很快,但大起大落,表现为不稳定、不规范、不健康、不完善,积累的深层次矛盾与效率低下的问题非常突出。本文详细分析了我国证券市场效率不高的原因,并提出了相应的对策。     

我国证券市场风险收益特征的行为基础

我国证券市场的风险收益具有以下特征:(1)资本资产定价模型所揭示的风险收益关系在我国股市并不显著。(2)我国证券市场系统性风险占整体风险的比例较高。(3)从趋势上看,无论个股还是行业系统性风险占整体风险的指标没有明显的下降趋势。这些特征根源于我国特定的投资者结构以及不同投资者的风险厌恶特性和对私人信息的偏好特性。因此,投资者应针对上述特征,在集中投资、反向交易和降低交易频率等方面调整交易策略,提高投资收益率。     

On the Non-Existence of Redundant Options

In a seminal paper, Ross (Q J Econ 90:75–89, 1976) shows that if security markets are resolving, then there exist (non-redundant) options that generate complete security markets. Complementing his work, Aliprantis and Tourky (2002) show that if security markets are strongly resolving and the number of primitive securities is less than half the number of states, then every option is non-redundant. Our paper extends Aliprantis and Tourky’s result to the case when their condition on the number of primitive securities is not imposed. Specifically, we show that if there exists no binary payoff vector in the asset span, then for each portfolio there exists a set of exercise prices of full measure such that any option on the portfolio with an exercise price in this set is non-redundant. Since the condition that there exists no binary payoff vector in the asset span holds generically, redundant options are thus rare. I am grateful to an anonymous referee for very helpful comments. Research support from the School of Business at The George Washington University is gratefully acknowledged     

我国证券纠纷调解机制的完善和金融申诉专员制度合理要素的借鉴

我国新修订的《证券法》于2020年3月1日正式施行。作为资本市场根本法规,《证券法》新增第六章"投资者保护"可谓亮点之一,其中第94条规定"强制调解制度"在诉讼和仲裁之外为投资者提供了新的维权路径,加强对投资者的事后保护。但目前我国证券纠纷调解机制仍有诸多问题,例如法律条文碎片化、调解协议刚性不足、调解衔接机制不完善、调解机构体系混乱、监督机制不力等,这些弊病从根本上严重影响证券纠纷调解机制的制度设计和程序运行。本文拟通过分析英国金融申诉专员制度的成熟经验,为我国证券纠纷调解机制的完善和发展提出优化路径。     

Interest-only and principal-only mortgage strips as interest-rate contingent claims

Interest-only (IO) and principal-only (PO) mortgage strips are valued in a stochastic interest-rate environment. The prepayment rate of the underlying mortgages is affected by two considerations not present in the pure financially rational model: (1) The property owner's holding period is assumed to follow a Gamma distribution, resulting in the possibility of prepayment due to the sale of the property (i.e., prepayment that is too early based on market interest rates); and (2) borrowers are assumed to face heterogeneous transaction costs related to refinancing the existing mortgage, and delay refinancing when market conditions make it optimal to do so (refinancing too late). Properties of IO/PO strips are identified by the finite difference method.     

Planning Your Own Debt

We model the Danish market for mortgage backed securities with a two-factor interest rate model and use a stochastic programming approach to analyse how an individual home-owner should initially compose and subsequently readjust his mortgage in an optimal way. Results show that the 'rules of thumb' used by financial institutions are reasonable, although best suited for more aggressive mortgagors, for whom the delivery option is of some value. More risk-averse investors should also re-adjust frequently, but use more diversified portfolios. Results are insensitive to whether a one- or two-factor model is used, provided the former is suitably calibrated.     

资产支持商业票据：中小企业融资新渠道

2005年资产证券化试点打开了证券化的空间，但试点证券化资产范围相对狭窄，没有触及中小企业的融资需求。资产支持商业票据提供了破题的一种选择。本文介绍了资产支持商业票据的发展概况、发展的市场动力、交易结构以及交易种类，并对一个具体案例进行了分析。     

法国公开要约收购制度的最新改革——以2006年《公开要约收购法》为中心

2006年3月31日，依欧盟转化《要约收购指令》之要求，法国颁布了《公开要约收购法》，对现有的公开要约收购制度进行了多方位、深层次的改革。从宏观上看，此次改革主要涉及四个方面，即金融证券管理局监管范围的改革、强制要约收购制度的改革、要约透明机制的改革以及反要约收购防御措施的改革。尽管改革的效果仍有待评估，但法国在此次改革中所体现的提高欧盟范围内企业竞争力的决心和表率作用无疑为欧盟经济一体化注入了新的活力。     

ON THE PROFITABILITY OF RESALE PRICE MAINTENANCE WHEN DEMAND IS UNCERTAIN

A previous study finds that in a market where a manufacturer faces uncertain demand and sells to consumers through competitive retailers, the manufacture wishes to support adequate retail inventories by imposing resale price maintenance (RPM). I show that if retail inventories are allocated to consumers through first‐come‐first‐served rule rather than efficient rationing rule in the game with unconstrained retail competition, imposing RPM may not be profitable. It may not encourage more retail inventories either. RPM may also lower consumer surpluses and social welfare. This study casts some doubt on the demand uncertainty theory that supports RPM.     

How does issuing contingent convertible bonds improve bank's solvency? A Value-at-Risk and Expected Shortfall approach

This paper examines how issuing an innovative financial instrument called contingent convertible bond (CoCo) may enhance bank's solvency in comparison to issuing a conventional bond. CoCos convert automatically into common equity or have a principal write-down when bank's regulatory capital fails to meet a predetermined level. They have been invented and put into legislation with an objective to absorb losses thus preventing institutions from bankruptcy. From the standpoint of an issuer CoCos bring about two counter effects regarding his solvency: on one hand they recapitalize a bank approaching insolvency on the other hand CoCos pay much higher coupon comparing to conventional bonds. In our model a bank has two funding alternatives: either to issue CoCos or conventional bonds. We measure issuer's default risk using the concept of Value-at-Risk (VaR) and Expected Shortfall (ES). We conclude that CoCos have the potential to strengthen the resilience of the issuer on the condition that the probability of conversion triggering is higher than the VaR's significance level. Our findings can be helpful to the policymakers and banks to better understand the impact of CoCos on issuer's solvency.