确定隐含波动率的总变分正则化方法

求解隐含波动率是一个典型的PDE反问题,传统的Tikhonov正则化方法往往导致解的过度光滑化.基于波动率的跳跃性、隔夜周末效应等及总变分正则化方法具有较好地保持图像边界的优点,本文以Black-Scholes理论为框架,把确定隐含波动率问题转化为一个抛物型方程的终端问题,进一步提出求解隐含波动率的总变分正则化方法,并证明了解的存在性.     

图书馆馆徽寓意及设计研究

不管是高校校园内的图书馆楼还是城市里的图书馆建筑，普遍以宏伟亮丽而著称，如能配以独具特色的馆徽，展现图书馆独特的文化底蕴，可使其成为图书馆独具魅力的文化品牌。阐述了馆徽的重要作用，结合部分图书馆馆徽实例，对馆徽寓意进行了赏析，并对馆徽的设计和构成元素进行了深入探讨。     

《白苍鹭》中姓名的象征意义

朱厄特是美国文学史上擅长描写新英格兰地方色彩的作家。《白苍鹭》是她的一篇短篇小说佳作。在该小说中,作者为叙述中出现的部分人和物取了普通的名字,并且巧妙地通过特定的语境赋予了它们丰富的象征意义,从而大大增强了小说的表现力和感染力,读起来意蕴深长,耐人寻味。     

高数解题中的常用方法--挖掘隐含条件

本文通过举例，说明挖掘隐含条件在高数解题中的重要作用。     

Predictive power and unbiasedness of implied forward charter rates

This paper examines the efficiency and predictive power of implied forward shipping charter rates. In particular, we examine whether implied forward 6‐month time‐charter rates, which are derived through the difference between time‐charters with different maturities based on the term structure model, are efficient and unbiased predictors of actual future time‐charter rates. Using a dataset for the period January 1989 to June 2003, results of different statistical tests, including the cointegration approach, suggest that implied forward rates are in fact unbiased predictors of future time‐charter rates in the dry bulk freight market. In addition, it is found that implied forward rates yield superior forecasts compared to alternative univariate and multivariate time series models. However, while the unbiasedness hypothesis is found to hold, on average, we find that chartering strategies based on simple trend‐following trading rules in this cyclical market are able to generate economic profits even out‐of‐sample. This highlights how standard tests for unbiasedness do not always capture cyclical predictable components in the market behaviour. Copyright © 2007 John Wiley & Sons, Ltd.     

关于在中国建立沉默权制度的思考

沉默权制度虽然在20世纪70年代以来经历了一些波动和变化，但其在刑事司法中的地位并未动摇，坚持和发展沉默权制度仍是当今世界刑事司法领域的一个基本趋势。沉默权包括默示沉默权和明示沉默权，两者相辅相成共同构成完整的沉默权制度。我国目前的刑事诉讼法中已经有默示沉默权的规定，只是没有明示沉默权的规定，我们应该完善沉默权制度，逐步建立明示沉默权。     

论《呼啸山庄》叙述主体间的分化

英国女作家艾米莉.勃朗特的著名小说《呼啸山庄》以其激越、暴烈、强劲的情绪强烈地震撼着人们的心灵。从小说中叙述主体间的关系入手,讨论各叙述主体之间的分化与冲突所构成的文本张力及其意义的复杂性和多元化,可进一步揭示:小说令人震撼的力量来自于其具有独创性和超越性的叙事艺术。     

虚拟学习社区学习有效性研究

对虚拟学习社区(VLC)的功能、特点、活动方式和学习有效性的影响因素、特征进行了分析,探究了虚拟学习社区学习有效性以及它在虚拟学习社区未来发展中的重要意义.     

Value at risk from econometric models and implied from currency options

This paper compares daily exchange rate value at risk estimates derived from econometric models with those implied by the prices of traded options. Univariate and multivariate GARCH models are employed in parallel with the simple historical and exponentially weighted moving average methods. Overall, we find that during periods of stability, the implied model tends to overestimate value at risk, hence over‐allocating capital. However, during turbulent periods, it is less responsive than the GARCH‐type models, resulting in an under‐allocation of capital and a greater number of failures. Hence our main conclusion, which has important implications for risk management, is that market expectations of future volatility and correlation, as determined from the prices of traded options, may not be optimal tools for determining value at risk. Therefore, alternative models for estimating volatility should be sought. Copyright © 2004 John Wiley & Sons, Ltd.     

也论“默示选择”——《涉外民事关系法律适用法》第三条之解析

《涉外民事关系法律适用法》第三条以"当事人依照法律规定可以明示选择涉外民事关系适用的法律"之内容对法律选择的方式加以限制,确立了"明示选择"的地位。而世界大多数国家在其涉外民事立法中肯定了"默示选择"的价值,承认或有限度地承认"默示选择"。"默示选择"并非是"不选择",更不是法官代替当事人来选择,其本身就是基于当事人"意思自治原则"的法律选择模式,体现了契约自由的精神。作为世界上少数几个完全不承认当事人"默示选择"的国家之一,我国的立法者应当看到"默示选择"所体现的价值以及世界其他国家相关立法内容的大趋势,并结合全球国际私法的新发展,对我国涉外立法的相关内容加以修改和完善。