Black the libertarian

The most serious challenge to Frankfurt-type counterexamples to the Principle of Alternate Possibilities (PAP) comes in the form of a dilemma: either the counterexample presupposes determinism, in which case it begs the question; or it does not presuppose determinism, in which case it fails to deliver on its promise to eliminate all alternatives that might plausibly be thought to satisfy PAP. I respond to this challenge with a counterexample in whichconsidering an alternative course of action is anecessary condition fordeciding to act otherwise, and the agent does not in fact consider the alternative. I call this a “buffer case,” because the morally relevant alternative is “buffered” by the requirement that the agent first consider the alternative. Suppose further that the agent’s considering an alternative action—entering the buffer zone—is what would trigger the counterfactual intervener. Then it would appear that PAP-relevant alternatives are out of reach. I defend this counterexample to PAP against three objections: that considering an alternative isitself a morally relevant alternative; that buffer cases can be shown to containother alternatives that arguably satisfy PAP; and that even if the agent’spresent access to PAP-relevant alternatives were eliminated, PAP could still be satisfied in virtue ofearlier alternatives. I conclude that alternative possibilities are a normal symptom, but not an essential constituent, of moral agency.     

On the Behavior of Random Walk Around Heavy Points

Consider a symmetric aperiodic random walk in Z ^d , d≥3. There are points (called heavy points) where the number of visits by the random walk is close to its maximum. We investigate the local times around these heavy points and show that they converge to a deterministic limit as the number of steps tends to infinity.     

基于存货质押融资业务的阶段贷款最优决策研究

存货质押融资业务作为解决中小企业融资的方式之一在国内外都有所发展,这种业务模式在解决银行和企业委托代理问题的同时,引入了新的银行与物流企业之间的委托代理问题。本文针对新的问题,引入阶段贷款的方法来控制风险和降低道德风险,运用参数函数比较了阶段贷款和一次性贷款的异同,得出了阶段贷款优于一次性贷款的结论,并通过运用合约作为阶段贷款的有效补充机制来更好的控制代理问题。     

基金投资中委托代理问题的博弈分析

由于基金市场中的信息不对称,以及基金管理者和投资者之间的利益不一致,使得逆向选择和道德风险这两类委托代理问题成为基金治理时的核心问题之一,关于它们的研究对于保护投资者权益,发展和完善基金市场都有重要意义.从博弈分析的角度出发,通过建立不同的动态博弈模型,研究了这两类委托代理问题在基金市场上存在的原因以及可能产生的主要影响,并在参数分析的基础上提出了一些解决问题的想法和建议.     

中小企业融资中的逆向选择和道德风险

针对我国中小企业融资难的难题,利用博弈论和信息经济学的有关理论知识,从定量的角度深入分析了中小企业融资中逆向选择和道德风险的形成过程和机理,从理论上论证了中小企业融资难的重要原因在于中小企业与金融机构之间信息分布的非对称,在此基础上并给出了降低或规避逆向选择和道德风险的途径.     

On the existence of local times: A geometric study

We present a general study relating the geometry of the graph of a real function to the existence of local times for the function. The general results obtained are applied to Gaussian processes, and we show that with probability 1 the sample functions of a nondifferentiable stationary Gaussian process with local times will be Jarnik functions. This extends earlier works of Lifschitz and Pitt, which gave examples of Gaussian processes without local times. An example is given of a Jarnik function without local times, thus answering negatively a question raised by Geman and Horowitz.     

Optimal dividends and bankruptcy procedures: Analysis of the Ornstein-Uhlenbeck process

This paper investigates the impact of bankruptcy procedures on optimal dividend barrier policies. We specifically focus on Chapter 11 of the US Bankruptcy Code, which allows a firm in default to continue its business for a certain period of time. Our model is based on the surplus of a firm that earns investment income at a constant rate of credit interest when it is in a creditworthy condition. The firm pays a debit interest rate that depends on the deficit level when it is in financial distress. Thus, the surplus follows an Ornstein-Uhlenbeck (OU) process with a negative surplus-dependent mean-reverting rate. Default and liquidation are modeled as distinguishable events by using an excursion time or occupation time framework. This paper demonstrates how the optimal dividend barrier can be obtained by deriving a closed-form solution for the dividend value function. It also characterizes the distributional property and expectation of bankruptcy time subject to the bankruptcy procedure. Our numerical examples show that under an optimal dividend barrier strategy, the bankruptcy procedure may not prolong the expected bankruptcy time in some situations.     

Occupation times of intervals until first passage times for spectrally negative Lévy processes

In this paper, we identify Laplace transforms of occupation times of intervals until first passage times for spectrally negative Lévy processes. New analytical identities for scale functions are derived and therefore the results are explicitly stated in terms of the scale functions of the process. Applications to option pricing and insurance risk models are also presented.     

超扩散过程的遍历定理

考虑初始测度为Ｌｅｂｅｓｇｕｅ测度μ 的一致椭圆超扩散过程，其分枝特征为ψ（狓，狕）＝犫（狓）狕＋γ（狓）狕２．该文研究这类超过程的占位时过程的极限性质．对系数犫（狓）及γ（狓）做必要的限制，得到了占位时过程在空间维数犱≤２的遍历定理，我们的结果是［６］的补充．     

带移民超布朗运动的占位时中偏差

本文证明了当底空间维数d≥3时,一类带移民超布朗运动占位时过程的中偏差,其移民由Lebesgue 测度控制.可以清楚地看出,中偏差的规范化因子和速度函数恰好介于中心极限定理和大偏差之间,在 这个意义下,中偏差填补了中心极限定理和大偏差之间的空白.