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61.
文章提出开发和整合各种体育课程资源,以丰富体育课堂教学内容,使体育课程更具趣味性,激发学生学习体育的兴趣,充分发挥课程资源优势,将学校体育延伸到终身体育,更好地达成体育课程目标.  相似文献   
62.
本文论述创造良好的体育课堂教学气氛,对培养学生独立思考能力,发展学生非智力因素起到积极作用。  相似文献   
63.
This paper provides a unified treatment of oil stockpiling and demand restraint as policy responses for enhancing energy security and examines the implications of recent changes in the structure and performance of the international oil market for the design of policies. These issues are addressed using a dynamic programming framework in which international policy actions of key oil-importing countries are modeled as a Nash dynamic game. Significant policy implications from the analysis include: (1) the result that, with realistic assumptions about disruption risks and inventory capacities, differences between noncooperative and coordinated stockpile policies appear to be minor and (2) significant mutual gains could be reaped from a modest degree of collective restraint on normal market oil demand. The broader role of international cooperation in enhancing energy security is also discussed.  相似文献   
64.
This paper uses longitudinal survey data to assess factors affecting the duration of unemployment in Russia. We examine four types of marginalised labour force participants, according to ILO guidelines and survey responses, and we estimate duration models for each type. It turns out that the sets of characteristics with the strongest effects on the duration are remarkably similar across the different unemployment definitions and model specifications. Therefore, despite the formidable practical measurement problems, problematic groups of individuals can actually be identified. Received: 27 January 1999/Accepted: 27 January 2000  相似文献   
65.
This paper aims to derive explicit analytical solutions for Average Run Length (ARL) of CUSUM chart for the SARFIMA(P,D,Q)S process with exponential white noise. Measurement of performance was done with the ARL in terms of percentage error and CPU time. The results obtained from the explicit formulas were compared focusing on the performance using the numerical integral equation (NIE) method. Both methods had similarly excellent agreement with the percentage error at less than 0.25%. Meanwhile, the explicit formulas consumed less CPU time than the NIE method. It is clear that the explicit formulas are a good alternative in real applications.  相似文献   
66.
A frequency domain bootstrap (FDB) is a common technique to apply Efron’s independent and identically distributed resampling technique (Efron, 1979) to periodogram ordinates – especially normalized periodogram ordinates – by using spectral density estimates. The FDB method is applicable to several classes of statistics, such as estimators of the normalized spectral mean, the autocorrelation (but not autocovariance), the normalized spectral density function, and Whittle parameters. While this FDB method has been extensively studied with respect to short-range dependent time processes, there is a dearth of research on its use with long-range dependent time processes. Therefore, we propose an FDB methodology for ratio statistics under long-range dependence, using semi- and nonparametric spectral density estimates as a normalizing factor. It is shown that the FDB approximation allows for valid distribution estimation for a broad class of stationary, long-range (or short-range) dependent linear processes, without any stringent assumptions on the distribution of the underlying process. The results of a large simulation study show that the FDB approximation using a semi- or nonparametric spectral density estimator is often robust for various values of a long-memory parameter reflecting magnitude of dependence. We apply the proposed procedure to two data examples.  相似文献   
67.
We develop statistical inferential tools for estimating and comparing conditional tail expectation (CTE) functions, which are of considerable interest in actuarial science. In particular, we construct estimators for the CTE functions, develop the necessary asymptotic theory for the estimators, and then use the theory for constructing confidence intervals and bands for the functions. Both parametric and non-parametric approaches are explored. Simulation studies illustrate the performance of estimators in various situations. Results are obtained under minimal assumptions, and the general Vervaat process plays a crucial role in achieving these goals.  相似文献   
68.
One classical design criterion is to minimize the determinant of the covariance matrix of the regression estimates, and the designs are called D-optimal designs. To reflect the nature that the proposed models are only approximately true, we propose a robust design criterion to study response surface designs. Both the variance and bias are considered in the criterion. In particular, D-optimal minimax designs are investigated and constructed. Examples are given to compare D-optimal minimax designs with classical D-optimal designs.  相似文献   
69.
The study employs a sample of US S&P 100 firms to explore the driving factors affecting the level of board commitment. We modified Clark’s (1998) CANE model and developed a corporate CANE model that is applicable for board commitment. Supporting our model, we find that primary drivers of board commitment (through board personal agency) are non-financial factors including board independence, size, gender diversity, professional experience/skills, industrial and financial experiences, senior executives' compensation, and strictly board independence. These board compositions significantly enhance the level of board commitment, except the board size. On the other hand, whilst we find significant impact for the market-based factors, i.e. board commitment level tends to increase with market value (Tobin's Q), we find weak or no evidence on the effects of accounting-based factors. This suggests that the board task value is influenced by the actual perception of the market participants rather than ‘documented’ figures.  相似文献   
70.
This paper aims to determine, by means of regression analysis, which exported product groups, categorized according to their technological intensity, have the greatest effect on the movements in the volume of GDP p/c of the Western Balkan Countries (WBCs). The analysis, based on statistical-econometric methodology, includes 16 commodity groups per each WBC (Albania; Bosnia and Herzegovina; Croatia; FYR Macedonia; Montenegro; Serbia). The data were collected and presented in accordance with the HS4 system classification, which is also used for development of the ITC’s Trade Map. The results of the analysis show that those commodity groups produced by medium-low and low technology industries have the greatest effect on the change in the volume of GDP p/c in all WBCs in the period 2005–2015.  相似文献   
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