DEA评价模型应用的几点探讨

为更好地应用ＤＥＡ评价模型，本文讨论了ＤＥＡ模型中定性指标的模糊处理及权重分布的随机处理，运用主成分分析法对ＤＥＡ模型指标体系进行处理，并对ＤＥＡ评价结果进行了排队分析．     

A General Model of Some Inverse Combinatorial Optimization Problems and Its Solution Method Under l ∞ Norm

This paper proposes an optimization model and shows that most inverse combinatorial optimization problems so far discussed can be fit into this model as special cases. We propose a Newton-type algorithm for this model under l norm. This algorithm can solve the model in strongly polynomial time if the subproblem involved is solvable in strongly polynomial time for any fixed value of the parameter appearing in the subproblem, and it is shown that most particular inverse optimization problems encountered are this kind. Therefore, through this paper we show that a large group of inverse optimization problems can be handled in a uniform way and solved in strongly polynomial time.     

Finding a Noncrossing Steiner Forest in Plane Graphs Under a 2-Face Condition

Let G = (V,E) be a plane graph with nonnegative edge weights, and let be a family of k vertex sets , called nets. Then a noncrossing Steiner forest for in G is a set of k trees in G such that each tree connects all vertices, called terminals, in net N _i, any two trees in do not cross each other, and the sum of edge weights of all trees is minimum. In this paper we give an algorithm to find a noncrossing Steiner forest in a plane graph G for the case where all terminals in nets lie on any two of the face boundaries of G. The algorithm takes time if G has n vertices and each net contains a bounded number of terminals.     

"编译原理"课程的教学探索

"编译原理"课程由于其理论难度及目前本科学生中普遍存在的各种思想误区,造成难以取得理想的教学效果.针对这一现状,从如何提高学习热情,利用形象化教学手段使抽象理论具体化,合理组织实验及课程设计内容等方面入手,提出了相应对策.     

诉讼案件所再现的文书类型：以“淡新档案”为中心

清代地方官厅旧址的公文书经战后台湾大学戴炎辉教授整理成为可利用的“淡新档案”,其中所有诉讼案件的文书类型包括申诉书、诉状、指令书原稿、差役复命书、法庭记录、证文、字据。官厅间文书所再现的内容全面反映了当时州县的诉讼实态,弥足珍贵,具有极高的研究价值。     

论美与数学

"美”与"数学”似乎是相隔遥远的两个领域.美现实而单纯,数学抽象而复杂.数学美正是本文要诠释的观点.     

Multivariate forests with missing mixed outcomes

In this article, we propose a multivariate random forest method for multiple responses of mixed types with missing responses. Imputation is performed for each bootstrap sample used to build the individual trees that form the forest. The individual trees are built using a weighted splitting rule allowing downweighting of imputed observations. A simulation study shows the benefits of this approach over complete case analysis when missing responses are missing completely at random and missing at random (MAR). In particular, the gain in prediction accuracy of the proposed method is larger in the MAR case and also increases as the proportion of missing increases.     

Tests based on equivariant estimators

Let ?⁽¹⁾ and ?⁽²⁾ be location-equivariant estimators of an unknown location parameter μ. It is shown that the test for H₀: μ ≤ μ₀ versus H_A : μ > μ₀ that rejects H₀ if ?⁽¹⁾ is large is uniformly more powerful than the one that rejects H₀ if ?⁽²⁾ is large if and only if ?⁽²⁾ is “more dispersed” than ?⁽¹⁾. A similar result is obtained for tests on scale using the star-shaped ordering. Examples are given.     

Predicting Severity of Foreign Body Injuries in Children in Upper Airways: An Approach Based on Regression Trees

The entry of a small item into the upper airways is one of the leading causes of injuries in children up to 14 years old. The aim of this study is to characterize types of objects causing choking along with the features of the children involved in the accident and compare results with current standards. The European Survey on Foreign Bodies Injuries Study (ESFBI) collected data on foreign body injuries from 19 European countries. The data from ESFBI were selected according to the ICD-9-CM codes 933 (foreign body in the pharynx and larynx) and 934 (foreign body in the trachea, bronchi, and lungs). Both a classification tree and a linear discriminant analysis (LDA) have been set up to predict the probability that an injured child experiences a hospitalization. The classification tree provides flowchart-type decision rules and allows for analyzing the impact of the item features, the children characteristics, and the circumstances of the accidents on the severity of the foreign body injuries. Results showed that children younger than 3.5 who are involved in an accident have a high probability to experience a hospitalization.     

试论微型小说的环境描写

微型小说的环境描写，依托于具体的景与物的描写。其形式可分为无景之景、全景之景、特写之景和白描之景四种。这些形式主要通过借人物的活动来暗示、借情节的跳跃来弹塑、借诗意的笔调来美化等方式实现。微型小说的成功的环境描写，往往不拘传统，超越自身，可谓颇具匠心和充满活力。