“1~∞”型不定式的极限

学生确定"1∞"不定式的极限之所以困难,首先在于构造"1"有困难,其次不易根据题目类型和结构想到结合函数的连续性等知识来确定这类极限。文中主要介绍了利用第二个重要极限、构造"1"后利用第二个重要极限、利用连续性与等价无穷小、利用连续性与洛必达法则这几种方法确定"1∞"不定式的极限。     

Why Do Stock Prices Drop by Less Than the Amount of the Dividend? Evidence from a Unique Environment

Abstract:

This paper investigates the effect of a lack of an automated limit order adjustment mechanism on ex-dividend day stock price behavior in a unique environment in which there are no taxes on dividends and capital gains. It finds that the overnight drop in the ask price is smaller than the overnight drop in the bid price. In addition, the study finds that average price drops are smaller than the dividend amount for all dividend sizes. I also find no evidence of a sawtooth-shaped relationship between the dividend amount and the ex-day price drop. These results are generally consistent with the lack of an automated limit order adjustment mechanism.     

村庄重构中的社会资本情境与个体选择行为分析

从传统向现代的转型过程中,传统社会资本的逐渐消解与现代社会资本的不完全成长构成了当前中国农村社会资本的结构断裂性情境。由于受到社会资本的情境性限制,村民在村庄重构过程中的个体选择行为表现为一种经济理性与从众心理相结合的非理性选择,导致作为主体的农民在村庄重构中集体失语。培育农村现代社会资本成为解决当前村庄重构中农民利益保护的重要途径,也是社会资本对自身情境性限制的工具性超越。     

A note on the central limit theorem for the idleness process in a one‐sided reflected Ornstein–Uhlenbeck model

In this short communication, we present a (functional) central limit theorem for the idleness process of a one‐sided reflected Ornstein–Uhlenbeck proces.     

OPTIMAL HIGH‐FREQUENCY TRADING IN A PRO RATA MICROSTRUCTURE WITH PREDICTIVE INFORMATION

We propose a framework to study optimal trading policies in a one‐tick pro rata limit order book, as typically arises in short‐term interest rate futures contracts. The high‐frequency trader chooses to post either market orders or limit orders, which are represented, respectively, by impulse controls and regular controls. We discuss the consequences of the two main features of this microstructure: first, the limit orders are only partially executed, and therefore she has no control on the executed quantity. Second, the high‐frequency trader faces the overtrading risk, which is the risk of large variations in her inventory. The consequences of this risk are investigated in the context of optimal liquidation. The optimal trading problem is studied by stochastic control and dynamic programming methods, and we provide the associated numerical resolution procedure and prove its convergence. We propose dimension reduction techniques in several cases of practical interest. We also detail a high‐frequency trading strategy in the case where a (predictive) directional information on the price is available. Each of the resulting strategies is illustrated by numerical tests.     

清代山西的田地数字及其变动

尽管光绪《山西通志》中记载的田地数字不是完全通过实际丈量得来的计量亩,但在目前没有其它更为系统全面和准确真实数字的情况下,其价值是不可替代的。特别是在考虑到资料性质在时间上的前后同一性和空间上的区域相似性情况下,其土地数字的变动应该基本上可以反映清代山西各地土地垦殖的变化情况。从先绪《山西通志》的记载看,清代山西各地田地数字的变化与当地的自然条件、开发历史和土地垦殖限度都有着很大关系。     

农民财产权收入的土地财产权结构新探——权利束的法经济学观点

财产权制度通过界定农村土地财产权、调整农村土地市场交易行为而成为保障农民财产性收入的核心制度.反观现实中法律制度对农村土地财产权转让的制约,农村土地市场交易受到限制,造成农民财产性收入取得程序、方式以及效力方面的困境.反思大陆法系传统财产权理论,从权利束的法经济学观点出发找寻农村土地财产权结构的基点,以定限物权为核心设...     

国内外食品添加剂限量指标对照实施方法

文章通过分析国内外食品添加剂限量指标对照的需求,阐述了了解和掌握不同国家和地区的食品添加剂安全体系、范围和类别、编码与功能分类、食品分类是对照工作开展的基础,给出了国内外食品添加剂限量指标对照的主要信息并建立了对照实施路线。     

如何整合中职学校《机械制图》与《极限配合与测量技术基础》课程

《机械制图》与《极限配合与技术测量基础》两门课程是实践性和应用性很强的专业技术基础课,教学内容是密切相关、紧密配合的,对学生动手能力、专业能力及综合素质的形成具有非常重要的作用。结合《机械制图》教材的编写实践,谈谈是如何对《机械制图》与《极限配合与技术测量技术》这两门课进行整合的。     

限制金融企业集团内部交易数额研究

本文介绍了各国通过限制金融企业集团内部交易数额来控制金融企业集团内部交易风险的规定之后 ,探讨了是否应对各金融行业、不同国家集团成员、不同交易类型、不同金融行业的集团成员分别设定内部交易限额 ,并对我国限制金融企业集团内部交易数额提出相应建议。