Aging and political decision making on public pensions

In this paper decision making on public pensions in a representative democracy is modeled within the framework of the well-known two-overlapping-generations (OLG) general-equilibrium model with rational expectations. The model is used to analyze the effects of aging on the economy in general and on the evolution of public pension schemes in particular, where aging is interpreted as a combination of a decrease in the rate of population growth and an increase in the political influence of pensioners. Analytical results are derived for the long run as well as for the short run by the method of comparative statics and comparative dynamics respectively. It appears that an increase in transfers to the old is not guaranteed if due to aging their political power increases. JEL classification: J14, H55 Received April 5, 1995 / Accepted September 4, 1995     

A simple endogenous growth model with endogenous fertility: indeterminacy and uniqueness

This paper studies the equilibrium dynamics and indeterminacy of equilibria in an endogenous growth model with endogenous fertility choice. We characterize the conditions that give rise to an unique equilibrium as well as multiple equilibria. Whenever there exists a unique equilibrium, it will be globally determinate; when multiple equilibria arise, indeterminacy occurs. In particular, we find that two equilibria occur – one is associated with high fertility and low growth, while the other is associated with low fertility and high growth. A parameterized example is given to assess the empirical feasibility of our results. The validity of the neo-Malthusian relation between fertility and growth is then re-examined. Finally, we study the relation between growth and welfare and compare different balanced growth equilibria in terms of their lifetime-attained utility. JEL classifications: O41, J13 Received December 11, 1995 / Accepted October 20, 1996     

Dynamic microeconomic models of fertility choice: a survey

We review existing approaches to the specification and estimation of dynamic microeconomic models of fertility. Dynamic fertility models explain the evolution of fertility variates over the life-cycle as the solution to a dynamic programming model involving economic choices. Dynamic models may be classified into structural and reduced-form models. Structural models generally require solution of the underlying dynamic programming problem. Reduced-form models, while based on a structural specification, do not. Recent innovations in estimation methodologies make both types practical and realistic alternatives to static models of lifetime fertility. JEL classification: J13, C41, C61 Received August 26, 1994/Accepted October 23, 1996     

Child labor versus educational attainment: some evidence from Latin America

The paper addresses the issue of child labor in relation to the educational attainment of working children. The empirical analysis is based on household surveys in Bolivia and Venezuela. It was found that labor force participation is non-trivial among those below the legal working age or supposed to be in school. Working children contribute significantly to total household income. The fact that a child is working reduces his or her educational attainment by about 2 years of schooling relative to the control group of non-working children. Grade repetition, a common phenomenon in Latin America, is closely associated with child labor. JEL classification: J13, J21, I21 Received May 2, 1996/Accepted August 14, 1996     

Problem characteristics, decision processes and evaluation activity: a preliminary study of mental health center directors

This article reports on the results of a preliminary study on the characteristics of problems and problem solving in mental health centers. The major findings were that directors were generally quite satisfied both with the available level of information intended to help them make decisions, and with their ability to make good, even optimal, decisions. Much of this confidence resulted from the use of assumptions about the problems which reduced the need for empirical information. The problem solving process was highly dynamic and interactive, with changes over time in the characteristics of problems, constraints and alternative solutions. The directors played an active role in attempting to foster and influence the direction of many of these instabilities. Some implications for evaluation and research are discussed.     

The Economic Efficiency of Sampling Size: The Case of Beef Trim Revisited

A recent paper by Ferrier and Buzby provides a framework for selecting the sample size when testing a lot of beef trim for Escherichia coli O157:H7 that equates the averted costs of recalls and health damages from contaminated meats sold to consumers with the increased costs of testing while allowing for uncertainty about the underlying prevalence of contamination. Ferrier and Buzby conclude that the optimal sample size is larger than the current sample size. However, Ferrier and Buzby's optimization model has a number of errors, and their simulations failed to consider available evidence about the likelihood of the scenarios explored under the model. After correctly modeling microbial prevalence as dependent on portion size and selecting model inputs based on available evidence, the model suggests that the optimal sample size is zero under most plausible scenarios. It does not follow, however, that sampling beef trim for E. coli O157:H7, or food safety sampling more generally, should be abandoned. Sampling is not generally cost effective as a direct consumer safety control measure due to the extremely large sample sizes required to provide a high degree of confidence of detecting very low acceptable defect levels. Food safety verification sampling creates economic incentives for food producing firms to develop, implement, and maintain effective control measures that limit the probability and degree of noncompliance with regulatory limits or private contract specifications.     

论曹丕《典论·论文》

在中国文学理论批评史上,曹丕的《典论·论文》提供了许多新内容。"诗赋欲丽"把诗赋文体的审美和娱乐功能推到极致。但作于建安末年的《典论·论文》,其主旨却是要消弭受儒家经学浸淫至深的士人的抵抗情绪,使士人与世无争,惟以著述为追求。     

利用工业废硅胶制活性白炭黑

工业废硅胶用一定浓度的氢氧化钠处理，经过滤得水玻璃．在其中同时加入氯化钠溶液和稀硫酸，经酸化、过滤、水洗、干燥得活性白炭黑，产品指标和橡胶补强性能均达到有关标准.     

日本2001年社保基金投资体制与投资策略改革评述:问题与前途

在2001年改革之前,日本中央社保基金“年金积立金”始终是通过“财政投融资计画”这个机构对产业和基础设施等领域进行投资来实现其增值保值的目的,结果出现了大量的坏账损失。鉴于此,2001年4月日本开始对社保基金投资管理体制进行大幅度的改革,新成立的“年金资金运用基金”代之以原来的“财政投融资计画”负责基金的投资运营,开始实施市场化的投资策略改革,将投资开始向资本市场倾斜。本文对2001年以来的改革过程和绩效进行了实事求是的分析,在占有大量第一手资料的基础上,首次对新体制的运行和存在的问题进行了评价,对我国社保基金的投资管理不乏具有特殊的启发。     

普惠性民办幼儿园的制度意蕴及实现路径思考

普惠性民办幼儿园作为实现学前教育普惠性改革发展目标的制度构建,所蕴含的意蕴在于扩展国家提供普惠性学前教育(园位)资源的渠道,让普通人能够获得最基本的学前教育服务需求。民办幼儿园满足一定条件经法定程序认定为普惠性幼儿园,可以享受国家相关政策优惠。国家对普惠性民办幼儿园的政策优惠区分为社会力量举办普惠性民办幼儿园扶持、引导政策,普惠性民办幼儿园面向社会提供普惠性学前教育(园位)资源的补助政策,以及普惠性民办幼儿园发展支持政策三个方面。