中国A股公司市盈率、市净率与ROE水平的关系研究

本文利用沪深两市1996年至2002年A股公司的数据,全面系统地研究了ROE水平与市盈率、市净率间的关系,分析了市盈率和市净率作为估值标准的合理性问题.检验结果表明,市净率与ROE水平间是非单调的函数关系,合理地反映了不同ROE水平公司未来业绩、风险和净资产的质量等基本面因素,是理想的估值标准;而市盈率受盈余管理影响很大,不是恰当的估值标准.     

Two Moments of the Logitnormal Distribution

We display the first two moment functions of the Logitnormal(μ, σ²) family of distributions, conveniently described in terms of the Normal mean, μ, and the Normal signal-to-noise ratio, μ/σ, parameters that generate the family. Long neglected on account of the numerical integrations required to compute them, awareness of these moment functions should aid the sensible interpretation of logistic regression statistics and the specification of “diffuse” prior distributions in hierarchical models, which can be deceiving. We also use numerical integration to compare the correlation between bivariate Logitnormal variables with the correlation between the bivariate Normal variables from which they are transformed.     

Flexible Copula Density Estimation with Penalized Hierarchical B‐splines

The paper introduces a new method for flexible spline fitting for copula density estimation. Spline coefficients are penalized to achieve a smooth fit. To weaken the curse of dimensionality, instead of a full tensor spline basis, a reduced tensor product based on so called sparse grids (Notes Numer. Fluid Mech. Multidiscip. Des., 31, 1991, 241‐251) is used. To achieve uniform margins of the copula density, linear constraints are placed on the spline coefficients, and quadratic programming is used to fit the model. Simulations and practical examples accompany the presentation.     

电子商务参与下的交易信用

世界经济迅速全球化、电子商务也得到了迅猛发展，全球和地区的商业合作已经成为各行业经营和管理的方式。不管在合作还是交易中交易信用的作用和需求都非常突出地显现出来了，作者通过对于国内外交易信用的调查，总结出国内信用体系建设的必要性、层次和方法以及应该注意的一些问题。     

基于J2EE的第三方物流管理信息系统分析与设计

分析了第三方物流的业务流程特点和系统需求,介绍了J2EE平台的基本知识和框架特点,并结合某物流公司的物流信息平台建设,探讨了基于J2EE平台的第三方物流管理信息系统的组织结构与设计技术.     

A study of BIB designs through support matrices

This paper deals with the existence and nonexistence of BIB designs with repeated blocks. The approach is an algebraic one. The concept of a support matrix is introduced and some of its basic properties are noted. Some basic examples of support matrices are given when the block size is 3. The connection between full column rank proper support matrices and irreducible designs is explored and some examples of such matrices are given.     

基于51单片机的小型温度测量系统

本文介绍了单线数字温度传感器DS18820的结构、特点、工作原理，设计了一种基于DS18820和AT89S52单片机的温度测量系统的硬件结构及汇蝙程序设计。     

On the distribution of quadratic functionals of the ordinary and fractional Brownian motions

In this paper we discuss some distributional properties of quadratic functionals of the ordinary and fractional Brownian motions (fBms). As far as the ordinary Brownian motion (Bm) is concerned, those properties have been established extensively. A transition from the Bm to the fBm is not straightforward. Some difficulties associated with dealing with the fBm are explained, and a way to solving the problem is indicated, and some conjectures are given.     

Comment on An and Schorfheide's Bayesian Analysis of DSGE Models

An and Schorfheide's article provides an excellent review of Bayesian estimation of DSGE models. Rather than recapitulating the points already made in this article, my comment focuses on three aspects. It proposes a convergence measure to take account of serial correlation of MCMC draws, explains why the DSGE-VAR framework for policy analysis can be improved by avoiding the ad hoc identification assumption, and discusses an alternative structural approach to model misspecification.     

在教学中提高A、B级英语考试水平

近几年来,高职高专的英语应用能力考试得到了大大的推广,当下进行的高职教育评估对该项考试的过级率更是提出了更高的要求。对高职高专的英语应用能力A、B级考试做的相关教学探索,实践证明相关的作法实施得到了良好的效果。