中国集体林产权制度改革回顾与展望

采用历史产权制度研究方法,利用详实的历史数据与信息,系统地分析改革开放以来中国集体林产权制度改革每个重要时期的改革内容与进程以及集体林地林木流转制度演化历程,发现改革开放四十年中国集体林所有权和家庭经营的基因没有变,变的是集体林地承包经营权的实现形式;指出集体林产权制度变迁道路中的困惑;提出未来集体林产权制度的选择路径。     

太原市古树资源空间分布特征及历史文化价值

太原市古树名木共计3 866株,隶属于30科52属62种,以枣树Zizyphus jujuba、国槐Sophora japonica、侧柏Platycladus orientalis、油松Pinus tabulaeformis等乡土树种为主。通过核密度分析发现太原市古树名木在太原市中东部地区形成9个核密度估计值较高的地区。古树名木数量最多的枣树、国槐、侧柏、和油松的主要聚集区分别位于太原市中部、东部和南部、南部地区及中部和东北部地区。并依据历史文献资料,从民间习俗、宗教信仰、古城历史等角度阐述这四种主要树种蕴含的历史文化价值。     

Finding Closest Targets in Non-Oriented DEA Models: The Case of Convex and Non-Convex Technologies

This paper draws attention for the fact that traditional Data Envelopment Analysis (DEA) models do not provide the closest possible targets (or peers) to inefficient units, and presents a procedure to obtain such targets.It focuses on non-oriented efficiency measures (which assume that production units are able to control, and thus change, inputs and outputs simultaneously) both measured in relation to a Free Disposal Hull (FDH) technology and in relation to a convex technology. The approaches developed for finding close targets are applied to a sample of Portuguese bank branches.     

Limit theorems for multivariate discrete distributions

According to the usual law of small numbers a multivariate Poisson distribution is derived by defining an appropriate model for multivariate Binomial distributions and examining their behaviour for large numbers of trials and small probabilities of marginal and simultaneous successes. The weak limit law is a generalization of Poisson's distribution to larger finite dimensions with arbitrary dependence structure. Compounding this multivariate Poisson distribution by a Gamma distribution results in a multivariate Pascal distribution which is again asymptotically multivariate Poisson. These Pascal distributions contain a class of multivariate geometric distributions. Finally the bivariate Binomial distribution is shown to be the limit law of appropriate bivariate hypergeometric distributions. Proving the limit theorems mentioned here as well as understanding the corresponding limit distributions becomes feasible by using probability generating functions.     

客户信用评级体系的校准度检验研究

利用多种统计量对客户信用评级体系进行校准度检验,以对其准确性做出定量评估。同时,使用这些统计量对由两种不同方法构造的信用评级进行了实证对比检验,结果表明,校准度检验能够对客户信用评级的准确性做出有效评估。     

华北油田冀中电网输配电线路存在的主要问题及应对措施

本文论述了华北油田冀中电网输电线路存在的老化、线路下方违章建筑物、树木顶线、杆塔缺土、施工车辆、挖掘机、吊车误碰导线跳闸等情况,并提出了应对措施。     

我国可转换债券价值影响因素的敏感度分析

本文采用修正的二叉树模型,对影响可转换债券价值的影响因素进行敏感度分析。分析结果表明,基础股价、股价波动率和公司债券利率是可转债价值最重要的影响因素。本文的分析和结论对于将来构建可转债多因素定价模型和从事可转债的套利分析具有较高的参考价值。     

Category management and consumer choice

This paper shows the results of an exploratory analysis of the structure of a complex product category: Wine. In complex categories, a usual strategy of consumers is the partitioning of alternatives into homogeneous subsets and the sequential eliminations of subsets until a product/brand is chosen from among few homogeneous alternatives in the last subset. To identify if there is such a kind of strategy and the product attributes involved is of great interest for the retailer. After a discussion of the different modelling alternatives of the choice process, the authors provide an application of the additive trees (ADDTREE) model to explore the hierarchical structure. The ADDTREE results provide a first overview of the competitive market structure of the wine category: competition becomes more intense as the wine category is partitioned by, first, the type of wine criteria and, second, the designation of origin (DO) criteria.