Data skeletons: simultaneous estimation of multiple quantiles for massive streaming datasets with applications to density estimation

We consider the problem of density estimation when the data is in the form of a continuous stream with no fixed length. In this setting, implementations of the usual methods of density estimation such as kernel density estimation are problematic. We propose a method of density estimation for massive datasets that is based upon taking the derivative of a smooth curve that has been fit through a set of quantile estimates. To achieve this, a low-storage, single-pass, sequential method is proposed for simultaneous estimation of multiple quantiles for massive datasets that form the basis of this method of density estimation. For comparison, we also consider a sequential kernel density estimator. The proposed methods are shown through simulation study to perform well and to have several distinct advantages over existing methods.     

Constrained allocation problems with single-peaked preferences: An axiomatic analysis

We introduce a new class of problems that contains two existing classes: allocation problems with single-peaked preferences and bankruptcy problems. On this class, we analyze the implications of well-known properties such as Pareto optimality, strategy-proofness, resource-monotonicity, no-envy, equal treatment of equals, and two new properties we introduce, hierarchical no-envy and independence of nonbinding constraints. Unlike earlier literature, we consider rules that allow free-disposability. We present characterizations of a rule we introduce on this domain. We relate this rule to well-known rules on the aforementioned subdomains. Based on this relation, we present a characterization of a well-known bankruptcy rule called the constrained equal awards rule. Received: 22 June 2000/Accepted: 21 March 2002 This paper is based on the first chapter of my Ph.D. thesis submitted to the University of Rochester. I wish to thank my advisor, William Thomson, for helpful comments and suggestions.     

城市发展中土地供应调控机制初探

一、我国城市土地供应机制的基本特点 1.以需定供,总量不限 我国大多数城市土地供应基本上采用"以需定供,总量不限"的方式,由于城市土地利用规划的滞后,土地管理的力度尚待加强,加上地方政府片面强调"以地生财"、"筑巢引凤",城市土地的供应往往缺乏时段性和空间性,在土地供应总量上也基本没有严格的限制.     

经济责任审计风险的成因与防范

经济责任审计是一项非常严肃的工作。审计评价是否恰当 ,不仅影响对领导干部的业绩评估 ,而且直接关系到审计机关的信誉和形象。这就要求审计人员客观公正 ,尽量降低审计风险。     

International Tax Competition: A Case for International Cooperation in Globalization

The liberalization of international financial flows and foreign direct investment has induced countries to use diverse measures to attract inflow of foreign capital and foreign direct investment, which is expected to have a positive effect on the growth of GDP and thus a positive effect on social welfare. Tax exemption, reduction of tax rate, tax holiday, or diverse subsidies are some of the most important measures used. In this paper we study international tax cooperation, i.e., countries change and especially reduce tax rate for corporate income or for asset revenues to attract inflow of foreign direct investment. Both theoretical and empirical studies have shown the sensibility of foreign direct investment decision with respect to tax rate differences between home countries and host countries. In general, more inflow of foreign direct investment can be expected if the tax rate of the home country is lower than that of foreign countries. This is the main reason for international tax cooperation. In this paper we propose a simple model to prove the sub-optimal Nash non cooperative solution in a two-country tax-competition game. The model shows that international tax cooperation can improve welfare of the participating countries. How to reach a cooperative solution for an international tax competition game (ITCG) is therefore an important issue for further discussions and studies. International institutions can play a crucial role to reach international tax cooperation or international tax harmonization.     

政府投资与扶持:解决农村公共产品短缺的中坚力量——渠县农村公共产品供给的调查报告

农村公共产品对农村经济和社会发展起着基础性作用,它与农村经济社会发展和广大农民的幸福安康息息相关.以政府为主导的农村公共产品供给制度对我国农村经济社会的发展能起到非常重要的作用.作为农村经济发展基础的公共产品供给是实施城乡统筹发展战略,也是实现和谐社会和全面建设小康社会社会的重要途径,政府在农村公共产品的供给方面责无旁贷.面对农村与世界市场经济的接轨和重大的经济结构调整对农村公共产品的巨大需需求和现代农民日益增长的物质文化生活水平的需求,农村公共产品短缺的问题是当地政府应当高度重视的问题.