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991.
对外技术依存度是我国测度创新型国家建设进程的重要指标。本文提出基于全球化视角的对外技术依存度测算方法,考虑了外资企业的影响,使指标反映的内容更加全面。以大中型工业企业为例,计算了近十年的对外技术依存度,并预测了未来十年的对外技术依存度。分析表明,2020年创新型国家对外技术依存度目标是能够实现的。  相似文献   
992.
ABSTRACT

The generalized Pareto distribution (GPD) is commonly used as extreme values's distribution. We present goodness of fit tests for the GPD based on Neyman's smooth tests statistics. The methods of maximum likelihood, moments and probability-weighted moments are used for estimating the GPD's parameters. Simulations are done to study the power of these tests.  相似文献   
993.
The Darbellay–Vajda partition scheme is a well known method to estimate the information dependency. This estimator belongs to a class of data-dependent partition estimators. We would like to prove that with some simple conditions, the Darbellay–Vajda partition estimator is a strong consistency for the information dependency estimation of a bivariate random vector. This result is an extension of 20 and 21 work which gives some simple conditions to confirm that the Gessaman's partition estimator and the tree-quantization partition estimator, other estimators in the class of data-dependent partition estimators, are strongly consistent.  相似文献   
994.
The “traditional” approach to the estimation of count-panel-data models with fixed effects is the conditional maximum likelihood estimator. The pseudo maximum likelihood principle can be used in these models to obtain orthogonality conditions that generate a robust estimator. This estimator is inconsistent, however, when the instruments are not strictly exogenous. This article proposes a generalized method of moments estimator for count-panel-data models with fixed effects, based on a transformation of the conditional mean specification, that is consistent even when the explanatory variables are predetermined. Two applications are discussed, the relationship between patents and research and development expenditures and the explanation of technology transfer.  相似文献   
995.
孙川 《统计研究》2013,30(3):35-42
 信息通信技术(ICT)投资对经济增长和劳动生产率的提高具有显著影响,要想深入研究ICT投资对经济增长的作用,就必须以一套完整的ICT资本存量数据作为基础。为此,本文利用可获得的原始数据,在完成了确定ICT投资额的计算方法,估算折旧率和ICT价格指数等工作的基础上,运用永续存盘法估算了1980-2007年全国ICT资本存量和1997-2007年各地区ICT资本存量。  相似文献   
996.
《随机性模型》2013,29(2):149-171
Abstract

When routing dynamically randomly arriving messages, the controller of a high-speed communication network very often gets the information on the congestion state of down stream nodes only after a considerable delay, making that information irrelevant at decision epochs. We consider the situation where jobs arrive according to a Poisson process and must be routed to one of two (parallel) queues with exponential service time distributions (possibly with different means), without knowing the congestion state in one of the queues. However, the (conditional) probability distribution of the state of the unobservable queue can be computed by the router. We derive the joint probability distribution of the congestion states in both queues as a function of the routing policy. This allows us to identify optimal routing schemes for two types of frameworks: global optimization, in which the weighted sum of average queue lengths is minimized, and individual optimization, in which the goal is to minimize the expected delay of individual jobs.  相似文献   
997.
ABSTRACT

This paper describes some methods of constructing circular neighbor balanced and circular partially neighbor balanced block designs for estimation of direct and neighbor effects of the treatments. A class of circular neighbor balanced block designs with unequal block sizes is also proposed.  相似文献   
998.
ABSTRACT

The exponential-logarithmic distribution is a distribution which has a decreasing failure function and various applications such as in biological and engineering fields. In this paper, we study a change-point problem of this distribution. A procedure based on Schwarz information criterion is proposed to detect changes in parameters of this distribution. Simulations are conducted to indicate the performance of the proposed procedure under different scenarios. Applications on two real data are provided to illustrate the detection procedure.  相似文献   
999.
The purpose of this article is to develop algorithms for computing the exact Fisher information matrix of periodic time-varying state-space models. We first present a relatively simple recursive algorithm which computes the elements of the exact information matrix without involving numerical differentiation, since all required derivatives are analytically evaluated. The proposed algorithm extends the procedure due to Cavanaugh and Shumway (1996 Cavanaugh , J. E. , Shumway , R. H. ( 1996 ). On computing the expected Fisher information matrix for state-space model parameters . Statist. Probab. Lett. 26 : 347355 .[Crossref], [Web of Science ®] [Google Scholar]) to the periodic state-space framework. Exploiting the approach used in Klein et al. (2000 Klein , A. , Mélard , G. , Zahaf , T. ( 2000 ). Construction of the exact Fisher information matrix of Gaussian time series models by means of matrix differential rules . Linear Alg. Applic. 321 : 209232 .[Crossref], [Web of Science ®] [Google Scholar]), a second algorithm is proposed in order to obtain the exact information matrix as a whole instead of element by element. The algorithms are first developed in a general framework and then specialized to the case of a periodic Gaussian vector autoregressive moving-average (PVARMA) model.  相似文献   
1000.
Mixture modeling in general and expectation–maximization in particular are too cumbersome and confusing for applied health researchers. Consequently, the full potential of mixture modeling is not realized. To remedy the deficiency, this tutorial article is prepared. This article addresses important applied problems in survival analysis and handles them in deeper generality than the existing work, especially from the point of view of taking covariates into account. In specific, the article demonstrates the concepts, tools, and inferencial procedure of mixture modeling using head-and-neck cancer data and survival time after heart transplant surgery data.  相似文献   
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