A note on the existence of unique equivalent martingale measures in a Markovian setting

Simple sufficient conditions for the existence of a unique equivalent martingale measure are provided. Furthermore, these conditions give us a handle on situations where an equivalent martingale measure cannot exist. The existence of a unique equivalent martingale measure is of relevance to problems in mathematical finance. Two examples of models for which the question of existence was unresolved are studied. By means of our results existence of a unique equivalent measure up to an explosion time is proved.     

Impacts of Declining U.S. Retail Beef Demand on Farm-Level Beef Prices and Production

A systems model was estimated to determine the effects of declining U.S. retail beef demand on farm-level beef prices and production. Retail beef demand declined by nearly 66% from 1976 to 1999. Results indicate autonomous shifts in retail demand significantly impacted farm-level demands and production. Based on equilibrium multipliers, the 1976–99 reduction in beef demand decreased real slaughter cattle prices and production by 32.1% and 11.2%, respectively. Real feeder cattle prices and production decreased by 8.0% and 22.6%, respectively. Combining the decreases in farm prices and production, slaughter and feeder cattle producers experienced a real revenue reduction of $13.3 billion (61%) due to the long-term decline in demand.     

The Bell Curve in Psychological Research and Practice: Myth or Reality?

The expression “the bell curve” designs both a kind of statistical distribution and the title of a famous and controversial book by Herrnstein and Murray. The first is so attractive that the second refers to it to give more credibility to its questionable theories on intelligence. The point is that, during the 20th century, the bell curve has assumed a more and more important role in psychological research and practice and have become both a reality and a myth. In the first case (reality) we can assist to appropriate applications of a real useful statistical concept. In the second (myth) we can have two kinds of attitudes: one attitude is typical of those researchers who search for normality in all their data and variables, just as Parsifal used to search for the Holy Graal (we call this “the Parsifal attitude”); the other is typical of those researchers who give normality for granted and act as if it were a Platonic Idea (we call this “the Plato attitude”). The article discusses the role of the normal distribution in psychological research and practice and shows how it can be dangerous to treat the bell curve as a God or an Idol.     

神府—东胜矿区沙漠化趋势预测与防治措施

神府－东胜矿区在特定的自然地质环境和人为因素的影响下，土地沙漠化呈不断扩展的演化趋势。矿区大规模的开发建设，更加速了沙漠化进展。本文利用典型地段的沙漠化发展速率，依据矿区总体设计规模，对矿区自然沙漠化趋势和开矿新增沙漠化土地面积进行了定量预测，并提出了相应的防治措施。     

基于供应链管理的企业营销渠道创新

传统渠道链的内在缺陷和新竞争模式的外在压力迫使企业必须通过渠道创新以获得新的利润和竞争力。本文在借鉴供应链管理优势的基础上,从组织结构、成员关系和管理模式创新三方面入手,提出渠道构建的逆向模式,以实现渠道的系统优化及各成员的长远利益最大,并使得市场的覆盖更为有效。     

由临街地价推算区片价的方法探讨

如何利用临街样点地价推算区片平均地价及基准地价始终是城镇基准地价评估的一个难点。文章利用赤峰市的实际调查数据,分别采用临街贡献率和面积加权两种方法推算区片平均地价,并采用回归分析方法探讨区片价与临街地价之间的关系,结果证明两种方法所推算的区片平均价是基本一致的,而且区片价与临街地价之间呈“反S”曲线关系。     

浅析资本弱化与外资避税

随着现代资本结构理论的发展,国内外企业都在学习如何在实务中对其加以灵活应用,使企业价值最大化.资本弱化就是这样一种应用,其目的在于企业通过资本结构安排,改变其纳税义务,起到避税的作用.目前,来自发达国家的外资企业在这一避税手法的使用上已达到了十分成熟的阶段,再加上我国现行税制框架尚未对资本弱化进行识别、规范和控制,造成了我国大量的税收利益流失.另外,在我国已逐渐认识到问题的紧迫性的情况下,如何进行监管和控制也是一个很大的技术难题.     

如何界定反倾销调查中的"生产成本"概念

“生产成本”是反倾销调查中的核心问题。该文通过国际反倾销法“生产成本”概念的界定，分析了反倾销调查中企业“生产成本”的差异，提出了按照国际惯例进行调整的方法，以及为反倾销调查取证提供的承诺。     

The Relevance of Stock and Flow-Based Reporting Information In Assessing the Likelihood of Emergence from Corporate Financial Distress

A number of recent studies have shown that earnings information is less useful and value relevant when firms are financially troubled. This finding has given rise to the consideration of alternatives. In this paper, we examine the contributions of book value-based proxies (normal earnings and abandonment value) and flow-based proxies (earnings and operating accruals) to the assessment of the likelihood of emergence from financial distress. Our prior reasoning is that while book value-based proxies may provide information about potential future cash resources, flow-based proxies, because they capture the progress of reorganization efforts underway, as opposed to mere potential, should be relatively more useful in assessing the likelihood of emergence from distress. Our findings are consistent with this explanation. We document that the primary predictors of emergence are flow-based proxies—in particular, cash from operations, net of earnings.     

Modified efficient importance sampling for partially non‐Gaussian state space models

The construction of an importance density for partially non‐Gaussian state space models is crucial when simulation methods are used for likelihood evaluation, signal extraction, and forecasting. The method of efficient importance sampling is successful in this respect, but we show that it can be implemented in a computationally more efficient manner using standard Kalman filter and smoothing methods. Efficient importance sampling is generally applicable for a wide range of models, but it is typically a custom‐built procedure. For the class of partially non‐Gaussian state space models, we present a general method for efficient importance sampling. Our novel method makes the efficient importance sampling methodology more accessible because it does not require the computation of a (possibly) complicated density kernel that needs to be tracked for each time period. The new method is illustrated for a stochastic volatility model with a Student's t distribution.