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41.
创造性思维的时效是指创造性思维在一定的时间内所取得的思维成果。在追求创造性思维科学性的同时 ,力求其高效率是创造性思维的目的。我们要运用先进的思维工具 ,采用科学的思维方法 ,尽量减少创造性思维中的挫折和曲折 ,力戒不必要思维时间的浪费 ,以提高创造性思维的效率  相似文献   
42.
以心理学、语言学、哲学和方法论为指导 ,探析了英语上下位概念之间关系的认识论意义。确定英语上下位概念依靠语义分析和述谓结构 ,上下位概念的牢固建立和活用可增强学习者对世界和语言的认识和描述能力 ,完善其认识结构 ,拓宽其世界知识  相似文献   
43.
Summary. We model daily catches of fishing boats in the Grand Bank fishing grounds. We use data on catches per species for a number of vessels collected by the European Union in the context of the Northwest Atlantic Fisheries Organization. Many variables can be thought to influence the amount caught: a number of ship characteristics (such as the size of the ship, the fishing technique used and the mesh size of the nets) are obvious candidates, but one can also consider the season or the actual location of the catch. Our database leads to 28 possible regressors (arising from six continuous variables and four categorical variables, whose 22 levels are treated separately), resulting in a set of 177 million possible linear regression models for the log-catch. Zero observations are modelled separately through a probit model. Inference is based on Bayesian model averaging, using a Markov chain Monte Carlo approach. Particular attention is paid to the prediction of catches for single and aggregated ships.  相似文献   
44.
高校青年学生网络思想与法制教育的几点思考   总被引:5,自引:0,他引:5  
随着因特网的发展 ,网络上信息的内容日益呈现出其复杂性 ,世界观并没有完全形成的青年学生 ,很容易受到网上信息内容所隐含的意识形态的影响。正确辨别网络信息 ,正确对待网上游戏 ,抵制恶意信息流传 ,增强青年学生的自我控制能力 ,加强对他们的思想与法制教育 ,是高校实现人才培养目标的重要保证。  相似文献   
45.
阐述了或有事项引起的财务报表变动 ,建立了一套财务指标 ,分析了或有事项对企业财务能力的影响 ,并指出在不确定性会计处理中应注意的几个问题  相似文献   
46.
Sets of relatively short time series arise in many situations. One aspect of their analysis may be the detection of outlying series. We examine the performance of standard normal outlier tests applied to the means, or to simple functions of the means, of AR(1) series, not necessarily of equal lengths. Although unequal lengths of series implies that the means have unequal variances, that are only known approximately, it is shown that nominal significance levels hold good under most circumstances. Thus a standard outlier test can usefully be applied, avoiding the complication of estimating the time series' parameters. The test's power is affected by unequal lengths, being higher when the slippage occurs in one of the longer series  相似文献   
47.
Estimated associations between an outcome variable and misclassified covariates tend to be biased when the methods of estimation that ignore the classification error are applied. Available methods to account for misclassification often require the use of a validation sample (i.e. a gold standard). In practice, however, such a gold standard may be unavailable or impractical. We propose a Bayesian approach to adjust for misclassification in a binary covariate in the random effect logistic model when a gold standard is not available. This Markov Chain Monte Carlo (MCMC) approach uses two imperfect measures of a dichotomous exposure under the assumptions of conditional independence and non-differential misclassification. A simulated numerical example and a real clinical example are given to illustrate the proposed approach. Our results suggest that the estimated log odds of inpatient care and the corresponding standard deviation are much larger in our proposed method compared with the models ignoring misclassification. Ignoring misclassification produces downwardly biased estimates and underestimate uncertainty.  相似文献   
48.
K. Goda  H. P. Hong 《Risk analysis》2008,28(2):523-537
Seismic risk can be reduced by implementing newly developed seismic provisions in design codes. Furthermore, financial protection or enhanced utility and happiness for stakeholders could be gained through the purchase of earthquake insurance. If this is not so, there would be no market for such insurance. However, perceived benefit associated with insurance is not universally shared by stakeholders partly due to their diverse risk attitudes. This study investigates the implied seismic design preference with insurance options for decisionmakers of bounded rationality whose preferences could be adequately represented by the cumulative prospect theory (CPT). The investigation is focused on assessing the sensitivity of the implied seismic design preference with insurance options to model parameters of the CPT and to fair and unfair insurance arrangements. Numerical results suggest that human cognitive limitation and risk perception can affect the implied seismic design preference by the CPT significantly. The mandatory purchase of fair insurance will lead the implied seismic design preference to the optimum design level that is dictated by the minimum expected lifecycle cost rule. Unfair insurance decreases the expected gain as well as its associated variability, which is preferred by risk-averse decisionmakers. The obtained results of the implied preference for the combination of the seismic design level and insurance option suggest that property owners, financial institutions, and municipalities can take advantage of affordable insurance to establish successful seismic risk management strategies.  相似文献   
49.
The problem considered is that of finding an optimum measurement schedule to estimate population parameters in a nonlinear model when the patient effects are random. The paper presents examples of the use of sensitivity functions, derived from the General Equivalence Theorem for D-optimality, in the construction of optimum population designs for such schedules. With independent observations, the theorem applies to the potential inclusion of a single observation. However, in population designs the observations are correlated and the theorem applies to the inclusion of an additional measurement schedule. In one example, three groups of patients of differing size are subject to distinct schedules. Numerical, as opposed to analytical, calculation of the sensitivity function is advocated. The required covariances of the observations are found by simulation.  相似文献   
50.
论英语语言课程设计中的需求分析   总被引:1,自引:0,他引:1  
界定需求要从目标和目的两个方面进行,这两个方面是我们发展测试、材料、教学活动、评价策略的基础。因此需求分析是语言课程建设不可分割的一部分。本文重点介绍了英语语言课程设计中需求分析的方法及步骤。目的在于强调需求分析的重要性,以及需求分析对于教师改进教学方法、提高教学效果、提高学生学习的主动性和积极性的重要意义。  相似文献   
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