Exploring the mismatch between credit ratings and loss-given-default: A credit risk approach

It is commonly observed that high grade loans with better ratings are often associated with low recoveries if they default (i.e. with relatively high loss-given-default (LGD)). To address the mismatch problem, this paper proposes a credit risk approach by minimizing LGD for higher rated loans as a risk-rating matching standard in the sense that the decreasing LGD from creditors’ perspective is associated with higher credit rating for the borrower. This standard forces customers’ credit rating of each grade to be optimally determined in correspondence to its LGD, which means the LGD of high grade loans tends to be low. The approach is then tested using three credit datasets from China, i.e. credit data from 2044 farmers, 2157 small private businesses and 3111 SMEs. The empirical results show that the proposed approach indeed guides the way to solve the mismatch phenomenon between credit ratings and LGDs in the existing credit rating literature. By optimally determining credit ratings, the findings derived from this paper help provide a valuable reference for bankers, and bond investors to manage their credit risk.     

“投资人付费”vs.“发行人付费”:谁的信用评级质量更高？

本文选择2011-2015年被中债资信覆盖的发债A股上市公司作为主要研究对象,比较了“投资人付费”与“发行人付费”模式下的评级质量高低。研究发现:(1)与“发行人付费”评级相比,采用“投资人付费”模式的中债资信所作评级显著更低。(2)与“发行人付费”评级相比,当采用“投资人付费”模式的中债资信所作评级越低时,发行人未来盈利能力越差、预期违约风险越高,投资者要求的风险补偿也越高,这表明“投资人付费”模式下的信用评级质量更高。(3)“发行人付费”模式的评级结果可以在一定程度上反映公司的内部私有信息,但由于同时存在独立性缺失问题,“发行人付费”模式的信用评级质量仍然不如“投资人付费”模式的信用评级质量,这说明独立性对于评级机构尤其重要。     

The leverage effect and the basket-index put spread

Benchmark models that exogenously specify equity dynamics cannot explain the large spread in prices between put options written on individual banks and options written on the bank index during the financial crisis. However, theory requires that asset dynamics be specified exogenously and that endogenously determined equity dynamics exhibit a “leverage effect” that increases put prices by fattening the left tail of the distribution. The leverage effect is larger for puts on individual stocks than for puts on the index, thus increasing the basket-index spread. Time-series and cross-sectional variation in the leverage effect explains option prices well.     

Variance swaps valuation under non-affine GARCH models and their diffusion limits

In this article, we investigate the pricing and convergence of general non-affine non-Gaussian GARCH-based discretely sampled variance swaps. Explicit solutions for fair strike prices under two different sampling schemes are derived using the extended Girsanov principle as the pricing kernel candidate. Following standard assumptions on time-varying GARCH parameters, we show that these quantities converge respectively to fair strikes of discretely and continuously sampled variance swaps that are constructed based on the weak diffusion limit of the underlying GARCH model. An empirical study which relies on a joint estimation using both historical returns and VIX data indicates that an asymmetric heavier tailed distribution is more appropriate for modelling the GARCH innovations. Finally, we provide several numerical exercises to support our theoretical convergence results in which we further investigate the effect of the quadratic variation approximation for the realized variance, as well as the impact of discrete versus continuous-time modelling of asset returns.     

Consequences of Debt Forgiveness: Strategic Default Contagion and Lender Learning

I use a unique data set of loans to small business owners to examine whether lenders face adverse consequences when they grant debt forgiveness to borrowers. I provide evidence consistent with borrowers communicating their debt forgiveness to other borrowers, who then more frequently strategically default on their own obligations. This strategic default contagion is economically large. When the lender doubles debt forgiveness, the default rate increases by 10.9% on average. Using an exogenous shock to the lender's forgiveness policy, my findings suggest that as the lender learns about the extent of borrower communication the lender tightens its debt forgiveness policy to mitigate default contagion.     

不完全市场下的期权定价理论综述

由于B-S定价公式是在完全市场条件假设下推导出来的,这与现实存在很大的出路,因此后来的学者就针对市场条件状况,研究了不同市场条件下的期权定价,其中以不完全市场条件下的期权定价为主,这显然与事实更加吻合。不完全市场主要可以分为带交易费用的期权市场、存有违约风险的期权市场以及信息不完全的期权市场。文章在此基础上,分析总结了在这个市场假设条件下的研究现状,并给出了未来值得深入研究的方向:主要是进一步放松B-S定价模型的假设条件,引入更多的现实因素,深入研究不同市场状况下的期权定价问题。     

Pitfalls and perils of financial innovation: The use of CDS by corporate bond funds

We use the financial crisis of 2007–2009 as a laboratory to examine the costs and benefits of teams versus single managers in asset management. We find that when a fund uses complex trading strategies involving the use of CDS team-managed funds outperform solo-managed funds. This may be due to the greater diversity of expertise, experience and skill of teams relative to single managers. During the financial crisis, however, the performance premium of teams becomes negative, which may be because of the slower decision times of teams, which are especially costly during times of rapidly changing market conditions.     

金融中介职能、会计质量与债券违约风险——海龙短期融资券案例分析

利用案例分析方法分析了短期融资券"11海龙CP01"的发行和兑付过程,发现债券发行公司在发行债券前后均存在会计质量、公司运营以及内部治理等方面的问题,包括评级公司、承销商和会计师事务所在内的金融中介机构并未对这些问题及时披露,而这不利于信用风险市场化体系的建立,阻碍了债券市场的长期健康发展。     

Disentangling types of liquidity and testing limits-to-arbitrage theories in the CDS–bond basis

We disentangle asset-specific, market, and funding liquidity in the CDS–bond basis outside and during the 2007–9 global financial crisis. Our findings stress the importance of separating different types of liquidity, since all three measures have independently negative impacts on the basis. Funding liquidity emerges as the economically most important liquidity metric. While asset-specific liquidity is cross-correlated in both the cash and derivative markets, funding and market liquidity only matter for the cash market. We exploit the decomposition of the basis to test predictions of limits-to-arbitrage theories. We find strong evidence in favor of margin-based asset pricing and flight-to-quality effects.     

High-frequency credit spread information and macroeconomic forecast revision

We examine whether professional forecasters incorporate high-frequency information about credit conditions when revising their economic forecasts. Using a mixed data sampling regression approach, we find that daily credit spreads have significant predictive ability for monthly forecast revisions of output growth, at both the aggregate and individual forecast levels. The relationships are shown to be notably strong during ‘bad’ economic conditions, which suggests that forecasters anticipate more pronounced effects of credit tightening during economic downturns, indicating an amplification effect of financial developments on macroeconomic aggregates. The forecasts do not incorporate all financial information received in equal measures, implying the presence of information rigidities in the incorporation of credit spread information.