关于分类推进我国国有企业改革的思考

我国现有国有企业可以区分为一般竞争性领域的国有中小型企业、一般竞争性领域的国有大型企业、支柱产业领域的国有企业、非竞争性领域的国有企业等几种不同类型。对不同类型的国有企业应该按照不同的原则，采取不同的对策进行改革。     

Learning from Nuclear Accident Experience

Statistical procedures are developed to estimate accident occurrence rates from historical event records, to predict future rates and trends, and to estimate the accuracy of the rate estimates and predictions. Maximum likelihood estimation is applied to several learning models and results are compared to earlier graphical and analytical estimates. The models are based on (1) the cumulative number of operating years, (2) the cumulative number of plants built, and (3) accidents (explicitly), with the accident rate distinctly different before and after an accident. The statistical accuracies of the parameters estimated are obtained in analytical form using the Fisher information matrix. Using data on core damage accidents in electricity producing plants , it is estimated that the probability for a plant to have a serious flaw has decreased from 0.1 to 0.01 during the developmental phase of the nuclear industry. At the same time the equivalent frequency of accidents has decreased from 0.04 per reactor year to 0.0004 per reactor year, partly due to the increasing population of plants.     

Potential Negative Impacts of Nuclear Activities on Local Economies: Rethinking the Issue

Surveys of public opinion about perceptions of risk associated with the nuclear fuel cycle have shown that the public professes a widespread feeling of dread, a fear of associated stigmas, and a concern about possible catastrophic nuclear accidents. Various interest groups and state governments that oppose congressionally mandated siting of centralized high-level radioactive waste (HLW) storage and disposal facilities are using this negative imagery to create a powerful, emotional obstacle to the siting process. From statistical analyses of images and location preferences, researchers have claimed that possible significant economic losses could potentially accompany the siting of HLW facilities. However, several paradoxes, or self-contradictory statements, apparently exist between the responses expressed in surveys and the actual economic and demographic behavior evidenced in the marketplace. Federal policymakers need to evaluate whether the request for a change in siting policy is based on subjective fear of a potential negative economic effect or on proven negative effects. Empirically observed behavior does not support predicted negative economic effects based on survey responses.     

Effects of the Chernobyl Accident on Public Perceptions of Nuclear Plant Accident Risks

Assessments of public perceptions of the characteristics of a nuclear power plant accident and affective responses to its likelihood were conducted 5 months before and 1 month after the Chernobyl accident. Analyses of data from 69 residents of southwestern Washington showed significant test-retest correlations for only 10 of 18 variables--accident likelihood, three measures of impact characteristics, three measures of affective reactions, and hazard knowledge by governmental sources. Of these variables, only two had significant changes in mean ratings; frequency of thought and frequency of discussion about a nearby nuclear power plant both increased. While there were significant changes only for two personal consequences (expectations of cancer and genetic effects), both of these decreased. The results of this study indicate that more attention should be given to assessing the stability of risk perceptions over time. Moreover, the data demonstrate that experience with a major accident can actually decrease rather than increase perceptions of threat.     

How Fair Is Safe Enough? The Cultural Approach to Societal Technology Choice1

This paper consists of an argument and a pilot study. First is a general, perhaps philosophical, argument against the National Academy's viewpoint⁽¹⁾ that dealing with risk is a two-stage process consisting of (a) assessment of facts, and (b) evaluation of facts in sociopolitical context. We argue that societal risk intrinsically revolves around social relations as much as around evaluations of probability. Second, we outline one particular approach to analyzing societal risk management styles. We call this the fairness hypothesis. Rather than focusing on probabilities and magnitudes of undesired events, this approach emphasizes societal preferences for principles of achieving consent to a technology, distributing liabilities, and investing trust in institutions. Conflict rather than probability is the chief focus of this approach to societal risk management. This view is illustrated by a recent empirical pilot study that explored the fairness hypothesis in the context of new nuclear technologies.     

媒介生态平衡的演变与博弈——如何认识中国报业“拐点”

面对2005中国报业“拐点”,本文从媒介生态学角度,分析我国区域化报业市场格局与报业收入的单一性,发行竞争加剧到地市级城市报业市场面临重新洗牌的趋势,从五个方面探讨当前我国报纸如何打造核心竞争力,提升媒介生态位的途径。     

A Multiattribute Utility Analysis of Alternative Sites for the Disposal of Nuclear Waste

Five potential sites nominated for the Nation's first geologic repository for disposing of nuclear waste are evaluated using multiattribute utility analysis. The analysis was designed to aid the Department of Energy in its selection of 3 sites for characterization, a detailed data-gathering process that will involve the construction of exploratory shafts for underground testing and that may cost as much as $1 billion per site. The analysis produced insights into the relative advantages and disadvantages of the nominated sites and clarified current uncertainties regarding repository performance.     

An Analysis of the Portfolio of Sites to Characterize for Selecting a Nuclear Repository

The U.S. Department of Energy has selected three sites, from five nominated, to characterize for a nuclear repository to permanently dispose of nuclear waste. This decision was made without the benefit of an analysis of this "portfolio" problem. This paper analyzes different portfolios of three sites for simultaneous characterization and strategies for sequential characterization. Characterization of each site, which involves significant subsurface excavation, is now estimated to cost $1 billion. Mainly because of the high characterization costs, sequential characterization strategies are identified which are the equivalent of $1.7-2.0 billion less expensive than the selected DOE simultaneous characterization of the three sites. If three sites are simultaneously characterized, one portfolio is estimated to be the equivalent of $100-400 million better than the selected DOE portfolio. Because of these potential savings and several other complicating factors that may influence the relative desirability of characterization strategies, a thorough analysis of characterization strategies that addresses the likelihood of finding disqualifying conditions during site characterization, uncertainties, and dependencies in forecast site repository costs, preclosure and postclosure health and safety impacts, potential delays of both sequential and simultaneous characterization strategies, and the environmental, socioeconomic, and health and safety impacts of characterization activities is recommended.     

Uncertainty about Probability: A Decision Analysis Perspective

The issue of how to think about "uncertainty about probability" is framed and analyzed from the viewpoint of a decision analyst. The failure of nuclear power plants is used as an example. The key idea is to think of probability as describing a state of information on an uncertain event, and to pose the issue of uncertainty in this quantity as uncertainty about a number that would be definitive: it has the property that you would assign it as the probability if you knew it. Logical consistency requires that the probability to assign to a single occurrence in the absence of further information be the mean of the distribution of this definitive number, not the median as is sometimes suggested. Any decision that must be made without the benefit of further information must also be made using the mean of the definitive number's distribution. With this formulation, we find further that the probability of r occurrences in n exchangeable trials will depend on the first n moments of the definitive number's distribution. In making decisions, the expected value of clairvoyance on the occurrence of the event must be at least as great as that on the definitive number. If one of the events in question occurs, then the increase in probability of another such event is readily computed. This means, in terms of coin tossing, that unless one is absolutely sure of the fairness of a coin, seeing a head must increase the probability of heads, in distinction to usual thought. A numerical example for nuclear power shows that the failure of one plant of a group with a low probability of failure can significantly increase the probability that must be assigned to failure of a second plant in the group.     

鲁西地区产业结构优化的总体构想和产业发展序列研究

采用定量和定性相结合的分析方法及产业职能分类法,探讨了鲁西地区（京九铁路辐射地带）产业结构优化的总体构想和产业发展序列,提出了优先发展主导产业,积极扶持潜导产业;提高支柱产业素质,保持巩固已有的支柱作用;配套发展关联产业;有重点地发展基础性产业;拓宽“瓶颈”产业;大力发展乡镇企业的意见．