GAME CALL OPTIONS REVISITED

In this paper, having been inspired by the work of Kunita and Seko, we study the pricing of δ‐penalty game call options on a stock with a dividend payment. For the perpetual case, our result reveals that the optimal stopping region for the option seller depends crucially on the dividend rate d. More precisely, we show that when the penalty δ is small, there are two critical dividends 0 < d₁ < d₂ < ∞ such that the optimal stopping region for the option seller takes one of the following forms: (1) an interval if d < d₁; (2) a singleton if d∈ [d₁, d₂]; or (3) an empty set if d > d₂. When d∈ [d₁, d₂], the value function is not continuously differentiable at the optimal stopping boundary for the option seller, therefore our result in the perpetual case cannot be established by the free boundary approach with smooth‐fit conditions imposed on both free boundaries. For the finite time horizon case, the dependence of the optimal stopping region for the option seller on the time to maturity is exhibited; more precisely, when both δ and d are small, we show that there are two critical times 0 < T₁ < T₂ < T, such that the optimal stopping region for the option seller takes one of the following forms: (1) an interval if t < T₁; (2) a singleton if t∈ [T₁, T₂]; or (3) an empty set if t > T₂. In summary, for both the perpetual and the finite horizon cases, we characterize in terms of model parameters how the optimal stopping region for the option seller shrinks when the dividend rate d increases and the time to maturity decreases; these results complete the original work of Emmerling for the perpetual case and Kunita and Seko for the finite maturity case. In addition, for the finite time horizon case, we also extend the probabilistic method for the establishment of existence and regularity results of the classical American option pricing problem to the game option setting. Finally, we characterize the pair of optimal stopping boundaries for both the seller and the buyer as the unique pair of solutions to a couple of integral equations and provide numerical illustrations.     

我国未成年人罚金刑适用问题研究

近年来,我国未成年人犯罪呈上升趋势,除刑法规定的八种特殊情形外,刑法一般不对犯罪情节轻微的未成年人犯罪行为施以自由刑,而更多的适用罚金刑。因此,阐释了我国未成年人罚金刑的三种观点,对未成年人适用罚金刑存在的问题进行了分析,提出了完善我国未成年人适用罚金刑的相关建议,以期更好地发挥罚金刑的惩罚、威慑和感化等功能,加强对未成年人犯罪的惩罚和教育功能。     

商品流通领域执法问题研究

本文认为,执法是法律实施的重要环节,它维护着商品流通领域的法制和公正,执法不力将直接造成商品流通秩序混乱。商品流通领域的执法问题必须引起重视并迫切需要解决。文章提出,为解决当前商品流通领域存在的执法问题,必须加强商品流通行政管理机关执法队伍的建设,减少商品流通领域的多头执法和交叉执法,适当扩大商品流通行政管理机关的执法权力,赋予商品流通行政管理机关应急执法的权力,以坚决打击流通过程中的不法行为,维护流通主体的合法权益,保证商品流通活动健康、协调发展。     

论刑罚功能与再犯

刑罚的目的是预防犯罪,包括特殊预防与一般预防。但事实证明,现有刑罚已不再容易达到预防犯罪的目的,其功能不能有效发挥,甚至令人担忧。尤其是被法院本着＂宽和精神＂判处拘役、短期有期徒刑的罪犯,再犯现象严重。本文结合某地区再犯刑事案件统计情况进行分析,并提出对刑罚进行修改的建议。     

Analyzing yield, duration and convexity of mortgage loans under prepayment and default risks

In this article, we construct a general model, which considers the borrower’s financial and non-financial termination behavior, to derive the closed-form formula of the mortgage value for analyzing the yield, duration and convexity of the risky mortgage. Since the risks of prepayment and default are reasonably expounded in our model, our formulae are more appropriate than traditional mortgage formulae. We also analyze the effects of the prepayment penalty and partial prepayment on the yield, duration and convexity of a mortgage, and provide lenders with an upper-bound for the mortgage default insurance rate. Our model provides portfolio managers a useful framework to more appropriately appraise the mortgage and more effectively hedge their mortgage holdings. From the results of sensitivity analyses, we find that higher interest-rate, prepayment and default risks will increase the mortgage yield and reduce the duration and convexity of the mortgage.     

A distribution-free newsvendor model with balking and lost sales penalty

In this paper, we extend the classical single period newsvendor model in an environment of customer balking, which occurs when customers are reluctant to buy a product if its available inventory falls below a threshold level. Since failure to make a sale usually results in a cost penalty, in addition to the opportunity cost of lost sales, we incorporate such costs in our model. Furthermore, we extend our model to include fixed ordering costs. Our analysis is based on the assumption that only the mean and the variance of the distribution of demand are known, without assuming any specific distributional form. We illustrate the concepts developed here through simple numerical examples and demonstrate the effectiveness of our approach by solving a set of 1000 randomly generated test problems.     

建立惩罚机制 推进诚信纳税

我国失信纳税惩罚体制存在两大不足:信用征信难,失信纳税者得不到各职能部门的合力打击;制度安排不合理,守信者得不到应有的信用效益。要有效惩罚失信纳税行为,必须尽快建立起失信惩治机制,完善个人和企业征管体系;必须加强全民的税法知识教育,让全民了解纳税,监督纳税。     

未成年人犯罪主体的刑法适用

未成年人犯罪主体在认定、案件审判、刑罚适用上与成年人犯罪主体有很大区别。在司法实践中 ,对未成年人犯罪主体刑事责任的认定 ,应严格把握刑事责任年龄阶段的划分 ;审理未成年人刑事案件应采取适合未成年人的方式 ;刑罚适用上注意未成年人犯罪的量刑原则、刑罚种类、执行方面的特殊规定     

住房抵押贷款提前还贷风险管理研究

从现代金融和风险管理角度看,住房抵押贷款提前还贷对商业银行是一种期权性风险,对其收取违约金并非国际惯例,也并不是有效的风险补偿方式。商业银行应适应市场竞争需要,接受风险转嫁并提供风险管理服务,运用风险定价技术在按揭交易价格中对提前还贷风险进行补偿。对于已承担的风险,商业银行应构建抵押贷款提前还贷的数据库,通过表内对;中和市场对冲,推出多样化的住房抵押贷款方式,积极推进住房抵押贷款证券化．从而最终增强银行的盈利来源和核心竞争力。