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931.
21世纪是知识经济的时代。知识要素和人力资源 (即人才 )是知识经济的两个重要因素 ,知识的传播和人才的培养都离不开教育。该文以国家创新系统的人才层次结构为依据 ,提出林业创新系统的人才层次结构和林业创新人才的层次结构 ,并通过分析北京林业大学历年教师、学生的数据 ,得出在中国林业发展的三大阶段中林业创新人才培养的实际结构和未来结构 ,指出在知识创新的情况下 ,培养未来林业人才的趋势 相似文献
932.
Models of incomplete information have played a major role in the fields of political science and political economy. The models have almost exclusively been signaling models, and their substantive focus is frequently on situations in which the extensive form is not dictated by institutional requirements or procedures. We explore the relation between multiple-sender signaling games and the corresponding screening or mechanism design games without transfers and establish an equivalence result. If there is a fully-revealing equilibrium in the signaling game there is also a full-information optimal mechanism that yields the principal’s optimal policy in every state. The converse, that fully-revealing equilibria exist in the signaling game if a full-information optimal mechanism exists, is true if and only if the mechanism involves only the selection of policies that are optimal for some belief about the state. We also present two straightforward sufficient conditions for the existence of full-information optimal mechanisms. When either holds, fully-revealing equilibria in the signaling and screening games exist. The perceived advantage of the signaling over the screening approach – that no commitment by the principal is assumed – may be over-stated as flexibility in specifying off the path beliefs can mimic commitment. 相似文献
933.
袁明英 《北京林业大学学报(社会科学版)》2004,(Z1)
图书馆是高校的重要组成部分 ,其管理状况和作用的发挥关系到所在高校全局的发展。为了搞好图书馆建设 ,公共调查是一项经常性、基础性的工作。该文从高校图书馆公共调查的一般指标和方法的角度 ,结合高校图书馆的特点 ,提出了公共调查的一般思路、各业务板块的调查指标和方法设计及图书馆综合调查的要求和结构 相似文献
934.
It is argued that the abstract product attributes that consumers mention in a research setting should not be interpreted as combinations of the more concrete attributes consumers mention. Results from a laddering study show that a majority of elicited abstract product attributes are unrelated to concrete attributes. Furthermore, these unrelated abstract attributes are about different product aspects than the related abstract attributes. These findings are discussed in the light of the problem of ‘actionability', and of models for new product development. 相似文献
935.
Carla P. Davis 《The International migration review》2004,38(2):450-469
It is frequently noted that Cubans living in Miami are successful because they benefit from the formation of an enclave economy. Using the 1990 Census Public Use Microdata, this study broadens the examination beyond Miami to address the question of why Cubans living elsewhere have higher earnings than those in Miami. Specifically, I address the question of whether there is a relationship between Cuban ethnic enclave participation and Cuban income. Findings indicate that Cubans in Miami have the lowest personal income. Cubans living in areas with the lowest Cuban populations have the highest incomes. These findings are evidence against the enclave economy hypothesis. 相似文献
936.
王泽福 《北京林业大学学报(社会科学版)》2004,(Z1)
建设国际知名、国内高水平多科性研究型大学已成为北京林业大学的办学指导思想和奋斗目标 ,因此 ,图书馆面临着服务对象、服务内容、服务方式、服务针对性、服务层次等 5个方面的职能转换。针对形势变化和学校建设的需求 ,该文提出了图书馆在 4个方面的建设对策 :①建设研究型特色图书馆 ;②建设能提供深层次、全方位的文献信息导航服务的导航体系 ;③对文献信息资源进行重组和优化配置 ,建设特色馆藏 ;④启动支撑学科建设尤其是重点学科建设的“数字图书馆工程项目”。 相似文献
937.
孟莉 《北京林业大学学报(社会科学版)》2004,(Z1)
知识经济的核心是知识创新 ,而知识创新要求高等教育必须培养造就一批高素质的创新人才。数字化图书馆是高校图书馆发展的必然趋势。建设数字化图书馆对培养造就高素质的创新人才具有不可替代的重要作用。该文论述了数字化图书馆的概念、特征及其对培养高素质创新人才的重要作用 ,并提出了面向培养创新人才的数字化图书馆的建设方略 相似文献
938.
A constrained optimisation theory or choice in concurrent schedules of reinforcement is presented. The theory posits that subjects evaluate both reinforcement rates and the work rates required to produce them and select the most highly valued combination. The chosen reinforcement rate is obtained by efficiently allocating work rate across schedules. The theory provides a unified explanation for maximisation of the overall reinforcement rate, the law of least effort, choice under Conc FR FR, Conc VR VR. Conc VI VI and Conc VI VR schedules, and choice of work rate. 相似文献
939.
A mixture model with Laplace and normal components is fitted to wind shear data available in grouped form. A set of equations is presented for iteratively estimating the parameters of the model using an application of the EM algorithm. Twenty-four sets of data are examined with this technique, and the model is found to give a good fit to the data. Some hypotheses about the parameters in the model are discussed in light of the estimates obtained. 相似文献
940.
Joseph P. Romano 《Revue canadienne de statistique》1989,17(1):75-80
An important statistical problem is to construct a confidence set for some functional T(P) of some unknown probability distribution P. Typically, this involves approximating the sampling distribution Jn(P) of some pivot based on a sample of size n from P. A bootstrap procedure is to estimate Jn(P) by Jn(&Pcirc;n), where P?n is the empirical measure based on a sample of size n from P. Typically, one has that Jn(P) and Jn(P?n) are close in an appropriate sense. Two questions are addressed in this note. Are Jn(P) and Jn(P?n) uniformly close as P varies as well? If so, do confidence statements about T(P) possess a corresponding uniformity property? In the case T(P) = P, the answer to the first questions is yes; the answer to the second is no. However, bootstrap confidence statements about T(P) can be made uniform over a restricted, though large, class of P. Similar results apply to other functional T(P). 相似文献