Analysis of marginally specified semi-nonparametric models for clustered binary data

Generalized linear mixed models are widely used for analyzing clustered data. If the primary interest is in regression parameters, one can proceed alternatively, through the marginal mean model approach. In the present study, a joint model consisting of a marginal mean model and a cluster-specific conditional mean model is considered. This model is useful when both time-independent and time-dependent covariates are available. Furthermore our model is semi-parametric, as we assume a flexible, smooth semi-nonparametric density of the cluster-specific effects. This semi-nonparametric density-based approach outperforms the approach based on normality assumption with respect to some important features of 'between-cluster variation'. We employ a full likelihood-based approach and apply the Monte Carlo EM algorithm to analyze the model. A simulation study is carried out to demonstrate the consistency of the approach. Finally, we apply this to a study of long-term illness data.     

核电厂不同评价方法的比较研究

文章分析了核电厂评价体系的内涵、构成、功能,重点分析了不同评价方法之间的异同,为进一步提高中国核电厂评价体系的水平提供了参考。     

核地质系统工程产业发展思路

文章根据核地质系统的实际 ,提出实施人才战略、提高队伍素质 ;增加设备投入、壮大自身实力 ;加大经营力度 ,拓展目标市场 ;强化项目管理 ,提高经济效益 ;利用地勘优势 ,发展延伸产业等五条核地质系统工程产业发展思路。     

日本核电危机及其影响初步分析

日本核电危机已经产生了严重的后果与广泛影响。基于目前证实的转折性的政府决定、政策、措施,从核电规划、能源政策、核电与气候变化3个视角讨论了核电危机的潜在影响,具体体现在核能发展可能会更加审慎、能源政策中各因素的协调、全球核电复兴趋势可能终结等方面。     

Bayesian inference in cointegrated systems

In this paper I deal with Bayesian methods for conducting inference on important features of (potentially) cointegrated VAR models involving I(1) variables. Firstly, (informal) inference is made on the cointegrating rank of the system. Secondly, posterior analysis is used to verify the validity of over-identifying restrictions on the cointegration parameters. Thirdly, posterior distributions are obtained for impulse response functions and predictive densities at different horizons. The relevant posterior distributions are obtained by means of Monte Carlo integration. The analysis is based on the use of simple weakly informative priors. Two applications on simulated data and on the Danish money demand data are presented.     

矿物微粉对水泥基混合料抗压强度的影响

为了了解矿物微粉对混凝土性能的影响,利用可压缩堆积模型(CPM)计算了不同体系胶凝材料的堆积密实度,研究了矿物微粉级配及其相对掺量对低水胶比水泥基混合料抗压强度的影响。结果表明,胶凝材料的堆积密实度与水泥基混合料的抗压强度有很强的对应关系;当堆积密实度相差不大而化学效应相差较大时,化学效应越大,抗压强度越大。     

Nuclear Power

Nuclear power has never been free from the stifling involvement of government. Heavy regulation has reduced the ability of entrepreneurs to develop and provide new means for the generation of energy using nuclear fuel. The strict parameters dictated by government officials are based upon outdated technology, an improper regulatory philosophy, and preclude innovation in nuclear power generation. Anti-market environmentalists misunderstand the implications of a free market in nuclear power and argue against it based on problems that are actually caused by government involvement. Our position is neither for nor against nuclear power. We advocate a hands-off policy where the nuclear industry is left to its own devices, free from governmental regulations and subsidies: free to succeed or fail on its own. Thus, our position is neither right-wing conservative (removing regulations), nor left-wing liberal (removing subsidies). Very much to the contrary of both positions, we propose a free-market in nuclear power.     

Firm Density and Industry R & D Intensity: Theory and Evidence

By deriving a formal model of industry R & D that identifies factors influencing industry R & D intensity, this paper first suggests firm density, defined as the inverse of average firm sales or simply the number of firms divided by industry sales, as a measure of market structure that is appropriate in explaining industry R & D intensity. The model shows that the cost structure of R & D, consumer preference over quality and price, the appropriability of R & D, firm density, and the average level of firm R & D intensity jointly determine industry R & D intensity. In particular, firm density has a positive relationship with industry R & D intensity, implying that firms in higher firm-density industries feel fiercer competitive pressure and thus engage more intensively in R & D. An empirical analysis of panel data on industry R & D activities of Korean manufacturing industries during the period 1991–1996 provides supportive evidence for the predictions of the model including the positive relationship between firm density and industry R & D intensity. The theoretical model and the empirical results are also consistent with the recent survey of U.S. corporate R & D activities by the U.S. Department of Commerce and the National Science Foundation (1999).     

中国低密度住宅设计的工业化方向

针对中国城市低密度住宅现状,作者分析了其郊区化、大规模及平民化特征,提出“有人情味”的工业化将是低密度住宅在中国的发展方向。     

Spatial welfare economics versus ecological footprint: modeling agglomeration,externalities and trade

A welfare framework for the analysis of the spatial dimensions of sustainability is developed. It covers agglomeration effects, interregional trade, negative environmental externalities, and various land use categories. The model is used to compare rankings of spatial configurations according to evaluations based on social welfare and ecological footprint indicators. Five spatial configurations are considered for this purpose. The exercise is operationalized with the help of a two-region model of the economy, that is, in line with the ‘new economic geography.’ By generating a number of numerical ‘counter-examples,’ it is shown that the footprint method is inconsistent with an approach aimed at maximum social welfare. Unless environmental externalities are such a large problem that they overwhelm all other components of economic well-being, a ‘spatial welfare economic’ approach delivers totally different rankings of alternative land use configurations than the ecological footprint.