Correlated intensity,counter party risks,and dependent mortalities

In this paper we use an intensity-based framework to analyze and compute the correlated default probabilities, both in finance and actuarial sciences, following the idea of “change of measure” initiated by Collin-Dufresne et al. (2004). Our method is based on a representation theorem for joint survival probability among an arbitrary number of defaults, which works particularly effectively for certain types of correlated default models, including the counter-party risk models of Jarrow and Yu (2001) and related problems such as the phenomenon of “flight to quality”. The results are also useful in studying the recently observed dependent mortality for married couples involving spousal bereavement. In particular we study in details a problem of pricing Universal Variable Life (UVL) insurance products. The explicit formulae for the joint-life status and last-survivor status (or equivalently, the probability distribution of first-to-default and last-to-default in a multi-firm setting) enable us to derive the explicit solution to the indifference pricing formula without using any advanced results in partial differential equations.     

Pricing VXX option with default risk and positive volatility skew

This paper proposes and makes a comparative study of alternative models for VXX option pricing. Factors such as mean-reversion, jumps, default risk and positive volatility skew are taken into consideration. In particular, default risk is characterized by jump-to-default framework and the “positive volatility skew” issue is addressed by stochastic volatility of volatility and jumps. Daily calibration is conducted and comparative study of the models is performed to check whether they properly fit market prices and generate reasonable positive volatility skews and deltas. Overall, jump-to-default extended LRJ model with positive correlated stochastic volatility (called JDLRJSV in the paper) serves as the best model in all the required aspects.     

Estimation and evaluation of the term structure of credit default swaps: An empirical study

Chen, Cheng, Fabozzi and Liu [Chen, Ren-Raw, Cheng, Xiaolin, Fabozzi, Frank, Liu, Bo, 2008. An explicit, multi- factor credit default swap pricing model with correlated factors. J. Financial Quantitative Anal. 43 (1), 123-160] provide an explicit solution to the value of the credit default swap when the interest rate and the hazard rate are correlated. They also provide empirical evidence to support the model with transaction prices. In this paper, we extend their empirical work to study the term structure of CDS spreads by using a matrix CDS dataset from J. P. Morgan Chase. Matrix data contain interpolated prices based on traders’ expectations, which are often criticized as being “unreal”. However, the benefit of this matrix dataset is that it contains the entire credit spread curves, which allows us to understand the cross-sectional variation of the credit risk. The empirical results show that the parameters of the model are highly significant and it captures most of the cross-sectional as well as time series variation.     

利用传染模型对含有对手风险的信用证券定价(英文)

本文利用传染模型研究了可违约债券和含有对手风险的信用违约互换的定价。我们在约化模型中引入具有违约相关性的传染模型,该模型假设违约过程的强度依赖于由随机微分方程驱动的随机利率过程和交易对手的违约过程.本文模型可视为Jarrow和Yu(2001)及Hao和Ye(2011)中模型的推广.进一步地,我们利用随机指数的性质导出了可违约债券和含有对手风险的信用违约互换的定价公式并进行了数值分析.     

Calibrating affine stochastic mortality models using term assurance premiums

In this paper, we focus on the calibration of affine stochastic mortality models using term assurance premiums. We view term assurance contracts as a “swap” in which policyholders exchange cash flows (premiums vs. benefits) with an insurer analogous to a generic interest rate swap or credit default swap. Using a simple bootstrapping procedure, we derive the term structure of mortality rates from a stream of contract quotes with different maturities. This term structure is used to calibrate the parameters of affine stochastic mortality models where the survival probability is expressed in closed form. The Vasicek, Cox-Ingersoll-Ross, and jump-extended Vasicek models are considered for fitting the survival probabilities term structure. An evaluation of the performance of these models is provided with respect to premiums of three Italian insurance companies.     

Portfolio insurance: Gap risk under conditional multiples

The research on financial portfolio optimization has been originally developed by Markowitz (1952). It has been further extended in many directions, among them the portfolio insurance theory introduced by Leland and Rubinstein (1976) for the “Option Based Portfolio Insurance” (OBPI) and Perold (1986) for the “Constant Proportion Portfolio Insurance” method (CPPI). The recent financial crisis has dramatically emphasized the interest of such portfolio strategies. This paper examines the CPPI method when the multiple is allowed to vary over time. To control the risk of such portfolio management, a quantile approach is introduced together with expected shortfall criteria. In this framework, we provide explicit upper bounds on the multiple as function of past asset returns and volatilities. These values can be statistically estimated from financial data, using for example ARCH type models. We show how the multiple can be chosen in order to satisfy the guarantee condition, at a given level of probability and for various financial market conditions.     

A comparison of different quantity discount pricing policies in a two-echelon channel with stochastic and asymmetric demand information

In this paper, we study quantity discount pricing policies in a channel of one manufacturer and one retailer. The paper assumes that the channel faces a stochastic price-sensitive demand but the retailer can privately observe the realization of an uncertain demand parameter. The problem is analyzed as a Stackelberg game in which the manufacturer declares quantity discount pricing schemes to the retailer and then the retailer follows by selecting the retail price and associated quantity. Proposed in the paper are four quantity-discount pricing policies: “regular quantity discount”; “fixed percentage discount”; “incremental volume discount” and “fixed marginal-profit-rate discount”. Optimal solutions are derived, and numerical examples are presented to illustrate the efficiency of each discount policy.     

Large investor trading impacts on volatility

We begin with this paper a series devoted to a tentative model for the influence of hedging on the dynamics of an asset. We study here the case of a “large” investor and solve two problems in the context of such a model namely the question of the fair value (or liquidative value) of a “large” position and the question of pricing or hedging an option. In order to do so, we use a utility maximization approach and some new results in stochastic control theory.     

A reflection principle for correlated defaults

The correct valuation of the so-called “correlation products” in the credit risk market such as n$n$-th-to-default swaps or CDOs requires a better understanding of higher dimensional barrier default phenomena. We introduce a reflection principle suited for the pricing of credit derivatives on two securities, paving the way for the development of new methods in the field. For that purpose, we introduce new processes, the distributions of which involve generalized Bessel functions. As an application, we derive a closed formula for second-to-default digital swaps, under the standard Black–Cox hypothesis on the conditions triggering default.     

分数布朗运动下带违约风险的可转换债券定价模型

在股票价格、公司资产价值均服从分数次布朗运动且相关的条件下,利用风险对冲方法导出带违约风险的可转换债券定价模型;然后,通过解相关的偏微分方程得到其显式定价公式.