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1.
Scholarly periodicals in Iran are considered main information resources in the development of knowledge in scholarly areas. About 566 periodicals have publication licenses from the Commission of Scholarly Periodicals Evaluation of Ministry of Science, Research & Technology (MSRT), with sixty-eight published in English. This paper studies the publication delay of twenty-six Iranian scholarly periodicals which are published in Persian in Iran, not those Iranian journals which are published in English in Iran or out of the country. The peer review and scholarly publication processes in Iranian journals are quite lengthy and need improvement. There was no significant relationship between publication delay in Persian scholarly periodicals and their impact factor as presented by the Islamic World Science Citation Center (titled ISC). Finally, the authors offer some solutions for improving the publication system of Iranian scholarly journals and decreasing the publication interval of these journals.  相似文献   

2.
Summary It is known that the problem of combining a number of expert probability evaluations is frequently solved with additive or multiplicative rules. In this paper we try to show, with the help of a behavioural model, that the additive rule (or linear pooling) derives from the application of Bayesian reasoning. In another occasion we will discuss the multiplicative rule. Research supported by C.N.R. and Ministry of University and Technological and Scientific Research.  相似文献   

3.
Yan Ma 《Serials Review》2013,39(3):179-198
Abstract

This article presents an analysis of the Web presence of Chinese American newspapers and periodicals in the United States based on the author's last ten-year national survey of Chinese American newspapers and periodicals in the United States in 1997. The author reports on and updates the changes, development, variety, and status of Chinese American newspapers and periodicals and their Web editions. These publications and their Web presence have played a major role in maintaining the identity, cohesiveness, and structure of Chinese communities. They are the major sources for covering significant aspects of Chinese culture, including the historical, social, economic, and political development of Chinese Americans in the United States. Serials Review 2003; 29:179–198.  相似文献   

4.
In the case where the lagged dependent variables are included in the regression model, it is known that the ordinary least squares estimates (OLSE) are biased in small sample and that the bias increases as the number of the irrelevant variables increases. In this paper, based on the bootstrap methods, an attempt is made to obtain the unbiased estimates in autoregressive and non-Gaussian cases. We propose the residual-based bootstrap method in this paper. Some simulation studies are performed to examine whether the proposed estimation procedure works well or not. We obtain the results that it is possible to recover the true parameter values and that the proposed procedure gives us the less biased estimators than OLSE. This paper is a substantial revision of Tanizaki (2000). The normality assumption is adopted in Tanizaki (2000), but it is not required in this paper. The authors are grateful to an anonymous referee for valuable suggestions and comments. This research was partially supported by Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research (C)(2) #14530033, 2002–2005, for H. Tanizaki and Grants-in-Aid for the 21st Century COE Program.  相似文献   

5.
针对陕西省网站用户流失率超过80%反映出的陕西省互联网接入服务客户满意度指数很低的现实,构建互联网接入服务客户满意度模型,在对陕西省223家网站用户抽样问卷调查的基础上,运用结构方程模型,实证分析互联网接人服务客户满意度及其影响因素的关系,认定接人资费、客户沟通、硬件设施、服务质量及客户关怀对网站用户满意度都有显著影响,提出提升满意度的几点对策.  相似文献   

6.
The past decade has seen attempts by librarians and their allies to respond to inefficiencies in the market for scholarly journals and introduce infrastructure to support open solutions. Recently these efforts have contributed to success at the national level, first with the White House Office of Science and Technology Policy's 2013 policy memorandum on Expanding Public Access to the Results of Federally Funded Research and in 2014 with the Consolidated Appropriations Act, which incorporates the substance of the memorandum into law. This column provides a review of efforts by librarians to advocate for open scholarship, describes the federal actions that will expand public access to research, and concludes with a discussion of next steps in this evolving effort.  相似文献   

7.
科技期刊质量综合评价的主成分分析法及其改进   总被引:1,自引:0,他引:1  
应用主成分分析进行理工大学、工业综合类科技期刊质量综合评价,根据主成分累计贡献值确定主成分的有效维数和权重,消除由于指标间的相关性带来的偏差和人为确定指标权重引起的缺陷,使评价结果更客观、公正和准确。研究了评价指标数、期刊种类数等对评价结果的影响,从而确定了合理的评价指标,得到了可靠、有效的评价结果。在18个指标中,根据保留具有重要作用变量的原则,最终选定14个有效评价指标,并且对期刊质量都具有正向作用,其中引用刊教、学科扩散指标等5个指标最重要,而影响因子的重要性最低。  相似文献   

8.
Summary The paper first provides a short review of the most common microeconometric models including logit, probit, discrete choice, duration models, models for count data and Tobit-type models. In the second part we consider the situation that the micro data have undergone some anonymization procedure which has become an important issue since otherwise confidentiality would not be guaranteed. We shortly describe the most important approaches for data protection which also can be seen as creating errors of measurement by purpose. We also consider the possibility of correcting the estimation procedure while taking into account the anonymization procedure. We illustrate this for the case of binary data which are anonymized by ‘post-randomization’ and which are used in a probit model. We show the effect of ‘naive’ estimation, i. e. when disregarding the anonymization procedure. We also show that a ‘corrected’ estimate is available which is satisfactory in statistical terms. This is also true if parameters of the anonymization procedure have to be estimated, too. Research in this paper is related to the project “Faktische Anonymisierung wirtschaftsstatistischer Einzeldaten” financed by German Ministry of Research and Technology.  相似文献   

9.
This column's offerings cover late spring through summer to fall of 2011: NISO Webinar: The Future of Integrated Library Systems: Part 1: RDA & Cataloging (May 11); American Library Association Annual Conference (June 23–28); Association of College and Research Libraries New England Serials and Electronic Resources Interest Group Summer Program: Current Trends in E-Journals (August 18); Kentucky Library Association/Kentucky School Media Association Joint Conference (September 28–October 1); American Society for Information Science and Technology Annual Meeting (October 9–12); Great Lakes E-Summit Conference (October 10–11); and Potomac Technical Processing Librarians Annual Meeting (October 21).  相似文献   

10.
Increasing prices of scholarly journals have been subject to fierce discussion for several decades. In this paper the authors integrate influence factors of journal prices analyzed in different previous studies in a unified regression model based on current data. Three different models are calculated. In the first model (overall market) the largest influence was found for the size of the journal. Additionally, the authors calculate separate regression models for STM (Scientific, Technical, Medical) vs. HSS (Humanities and Social Sciences) journals and for for-profit vs. not-for-profit journals. The first comparison found that the influence of the number of published articles is much lower for HSS journals. The comparison between for-profit and not-for-profit journals showed that the influence of the circulation of a journal on its price is higher in the for-profit segment.  相似文献   

11.
Abstract

This column's offerings cover late spring through summer to fall of 2011: NISO Webinar: The Future of Integrated Library Systems: Part 1: RDA & Cataloging (May 11); American Library Association Annual Conference (June 23–28); Association of College and Research Libraries New England Serials and Electronic Resources Interest Group Summer Program: Current Trends in E-Journals (August 18); Kentucky Library Association/Kentucky School Media Association Joint Conference (September 28–October 1); American Society for Information Science and Technology Annual Meeting (October 9–12); Great Lakes E-Summit Conference (October 10–11); and Potomac Technical Processing Librarians Annual Meeting (October 21).  相似文献   

12.
The rapid development of the theory of robust estimation (Huber, 1973) has created a need for computational procedures to produce robust estimates. We will review a number of different computational approaches for robust linear regression but focus on one—iteratively reweighted least-squares (IRLS). The weight functions that we discuss are a part of a semi-portable subroutine library called ROSEPACK (RObust Statistical Estimation PACKage) that has been developed by the authors and Virginia Klema at the Computer Research Center of the National Bureau of Economic Research, Inc. in Cambridge, Mass. with the support of the National Science Foundation. This library (Klema, 1976) makes it relatively simple to implement an IRLS regression package.  相似文献   

13.
在综合考虑决策单元同质性和随机因素等影响的基础上,运用Bootstrap修正的DEA模型,对2010年中国教育部直属高校的科研活动效率进行了较为全面的评价和分析.研究结果表明:(1)统计检验显示出Bootstrap-DEA模型更合理,更具有可靠性;(2)中国教育部直属高校科研活动效率不仅存在较大改进空间,而且存在显著的个体差异;(3)规模效率均值显著高于相应的技术效率和纯技术效率,表明其并不是高校科研活动效率偏低的主要因素;(4)不同类型的高校科研活动效率差异是比较大的;(5)从纯技术效率和规模效率的比较看,大部分高校表现为两效率的双重低下或一高一低;(6)高校科研活动的纯技术效率与规模效率之间存在一定程度的不协调性.  相似文献   

14.
For the acquisition of periodicals and indexes, the selector role of subject specialists and reference librarians has been transformed by electronic access. In the past these librarians made independent recommendations for new periodicals, indexes, and abstracts by using traditional selection criteria (e.g., relevance, quality, and cost). With electronic resources, considerations such as licensing negotiations, consortial agreements, and technical issues have complicated the decision-making process and have sometimes removed it from individual librarians or even individual libraries. The author discusses the opportunities for individual librarians, particularly in public service roles, to participate in serials collection management decisions and provides a case study of business periodicals collection management in an academic library. Serials Review 2002; 28:283–286.  相似文献   

15.
Abstract

For authors, publishers, and researchers, the information roadmap charts and utilizes evolving technology. “Infomediary” is a new name for an old role, describing participation in both traditional and emerging ways to deliver information and publications. This article briefly defines the role of the infomediary and the types of services provided by companies such as Ingenta, ISI (Institute for Scientific Information), and Gale. The best infomediaries will provide rational order to the growing and changing base aggregation of published material as it moves from researcher to author to publisher to library and back to researcher, particularly as that material evolves from print to electronic form.  相似文献   

16.
Abstract

The Ruth H. Hooker Research Library has been delivering digital information to researchers' desktops at Naval Research Laboratory (NRL) sites across the country for over ten years. This article describes the current and planned efforts at unifying the various journals, databases, reference tools, and linking schemes into a comprehensive and integrated Web-based scientific and technical digital library for the benefit of the NRL and the broader naval research community. Serials Review 2003; 29:76–82.  相似文献   

17.
Abstract

For the acquisition of periodicals and indexes, the selector role of subject specialists and reference librarians has been transformed by electronic access. In the past these librarians made independent recommendations for new periodicals, indexes, and abstracts by using traditional selection criteria (e.g., relevance, quality, and cost). With electronic resources, considerations such as licensing negotiations, consortial agreements, and technical issues have complicated the decision-making process and have sometimes removed it from individual librarians or even individual libraries. The author discusses the opportunities for individual librarians, particularly in public service roles, to participate in serials collection management decisions and provides a case study of business periodicals collection management in an academic library. Serials Review 2002; 28:283–286.  相似文献   

18.
The focus of this installment of “The Balance Point” is “shelf-ready” print serials acquisitions, including functions associated with traditional consolidation services (ordering, receiving, check-in, labeling, claiming and batch shipments), and the newer capabilities of uploading check-in data automatically into library systems. Featured authors discuss traditional vendor consolidation services, pilot projects and experiments in the pursuit of what they define as genuinely “shelf-ready” periodicals. The authors view obtaining “shelf-ready” print journal issues as an effective and efficient means of managing print serials operations while coping with the demands of managing digital resource acquisitions with limited financial resources.  相似文献   

19.
Two wavelet based estimators are considered in this paper for the two parameters that characterize long range dependence processes. The first one is linear and is based on the statistical properties of the coefficients of a discrete wavelet transform of long range dependence processes. The estimator consists in measuring the slope (related to the long memory parameter) and the intercept (related to the variance of the process) of a linear regression after a discrete wavelet transform is performed (Veitch and Abry, 1999). In this paper its properties are reviewed, and analytic evidence is produced that the linear estimator is applicable only when the second parameter is unknown. To overcome this limitation a non linear wavelet based estimator - that takes into account that the intercept depends on the long memory parameter - is proposed here for the cases in which the second parameter is known or the only parameter of interest is the long memory parameter. Under the same hypothesis assumed for the linear estimator, the non linear estimator is shown to be asymptotically more efficient for the long memory parameter. Numerical simulations show that, even for small data sets, the bias is very small and the variance close to optimal. An application to ATM based Internet traffic is presented.Financial support from the Italian Ministry of University and Scientific Research (MIUR), also in the context of the COFIN 2002 ALINWEB (Algorithms for the Internet and the Web) Project, is gratefully acknowledged.  相似文献   

20.
The authors propose a reduction technique and versions of the EM algorithm and the vertex exchange method to perform constrained nonparametric maximum likelihood estimation of the cumulative distribution function given interval censored data. The constrained vertex exchange method can be used in practice to produce likelihood intervals for the cumulative distribution function. In particular, the authors show how to produce a confidence interval with known asymptotic coverage for the survival function given current status data.  相似文献   

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