Granularity of algorithmically constructed publication-level classifications of research publications: Identification of topics     

Peter Sjögårde  Per Ahlgren 《Journal of Informetrics》2018,12(1):133-152

The purpose of this study is to find a theoretically grounded, practically applicable and useful granularity level of an algorithmically constructed publication-level classification of research publications (ACPLC). The level addressed is the level of research topics. The methodology we propose uses synthesis papers and their reference articles to construct a baseline classification. A dataset of about 31 million publications, and their mutual citations relations, is used to obtain several ACPLCs of different granularity. Each ACPLC is compared to the baseline classification and the best performing ACPLC is identified. The results of two case studies show that the topics of the cases are closely associated with different classes of the identified ACPLC, and that these classes tend to treat only one topic. Further, the class size variation is moderate, and only a small proportion of the publications belong to very small classes. For these reasons, we conclude that the proposed methodology is suitable to determine the topic granularity level of an ACPLC and that the ACPLC identified by this methodology is useful for bibliometric analyses.  相似文献   

Four pitfalls in normalizing citation indicators: An investigation of ESI’s selection of highly cited papers     

Zhigang Hu  Wencan Tian  Shenmeng Xu  Chunbo Zhang  Xianwen Wang 《Journal of Informetrics》2018,12(4):1133-1145

InCites Essential Science Indicators is becoming increasingly used to identify top-performing research and evaluate the impact of institutes. Unfortunately, our study shows that ESI indicators, as well as other normalized citation indicators, have the following flaws. First, the publication month and the online-to-print delay affect a paper’s probability of becoming a Highly Cited Paper (HCP). Papers published in the earlier months of the year are more likely to accumulate enough citation counts to rank at the top 1% compared with those published in later months of the year. Papers with longer online-to-print delays have an apparent advantage for being selected as HCPs. Research field normalizations lead to the third pitfall. Different research fields have different citation thresholds for HCPs, making research field classification important for a journal. In addition, the uniform thresholds for both articles and reviews in ESI affect the reliability of HCP selection because, on average, reviews tend to have higher citation rates than articles. ESI’s selection of HCPs provides an intuitive feel for the problems of normalized citation impact indicators, such as those provided in InCites and SciVal.  相似文献   

数字调制类型的识别及实现     

宋全有  李万高 《商丘职业技术学院学报》2006,5(2):59-61

通信信号的调制识别是目前研究的热点问题.本文给出一种新的数字调制信号识别方法.高速数字专用芯片ADSP2101是此方法具体实现的重要器件,这一方法在实际通信中有着广泛的应用.  相似文献   

Assessing library topics using sentiment analysis in R: a discussion and code sample     

Brady D. Lund 《Public Services Quarterly》2020,16(2):112-123

Abstract

This article discusses the use of R programing language for executing a sentiment analysis of tweets pertaining to library topics. This discussion is situated within the literature of marketing and management sciences, which is employing methods of machine learning and business intelligence to make informed decision-making, and library administration, which has expressed great interest in social media engagement within its literature but has yet to adopt these types of analysis. Presented in this article is a sample code with instructions on how users may execute it within R to retrieve and analyze tweets relevant to library services. Two examples created using the code (analysis of top librarians’ tweets and analysis of posts about major book publishers) are used to demonstrate the functionality of the code. The code presented in this article may be used by libraries to analyze tweets about their library and library-related topics, which, in turn, may inform management and marketing design.  相似文献   

Writer identification approach based on bag of words with OBI features     

Amal Durou  Ibrahim Aref  Somaya Al-Maadeed  Ahmed Bouridane  Elhadj Benkhelifa 《Information processing & management》2019,56(2):354-366

Handwriter identification aims to simplify the task of forensic experts by providing them with semi-automated tools in order to enable them to narrow down the search to determine the final identification of an unknown handwritten sample. An identification algorithm aims to produce a list of predicted writers of the unknown handwritten sample ranked in terms of confidence measure metrics for use by the forensic expert will make the final decision.Most existing handwriter identification systems use either statistical or model-based approaches. To further improve the performances this paper proposes to deploy a combination of both approaches using Oriented Basic Image features and the concept of graphemes codebook. To reduce the resulting high dimensionality of the feature vector a Kernel Principal Component Analysis has been used. To gauge the effectiveness of the proposed method a performance analysis, using IAM dataset for English handwriting and ICFHR 2012 dataset for Arabic handwriting, has been carried out. The results obtained achieved an accuracy of 96% thus demonstrating its superiority when compared against similar techniques.  相似文献   

An NCME Instructional Module on Data Mining Methods for Classification and Regression     

Sandip Sinharay 《Educational Measurement》2016,35(3):38-54

Data mining methods for classification and regression are becoming increasingly popular in various scientific fields. However, these methods have not been explored much in educational measurement. This module first provides a review, which should be accessible to a wide audience in education measurement, of some of these methods. The module then demonstrates using three real‐data examples that these methods may lead to an improvement over traditionally used methods such as linear and logistic regression in educational measurement.  相似文献   

应收账款管理创新研究   总被引：1，自引：0，他引：1  

张尧洪 《宁波职业技术学院学报》2004,8(6):29-31

在传统应收账款管理方法的基础上，企业应运用维．帕累托(Vilfredo．Pareto)最优分析法对应收账款进行分类管理。即把已有客户分为核心客户、主要客户和一般客户，对他们实行不同的信用管理。对新客户运用稳健分析模型进行信用分析，然后做出销售决策。对销售人员确立应收账款管理目标，以应收账款质量提高作为目标管理的主要内容，企业销售人员的考核与应收账款质量的提高挂钩，建立应收账款管理的激励和约束机制。  相似文献   

小说《简爱》中梦境的审美分析     

龙丽伟  魏现江 《铜仁学院学报》2007,1(4):26-29

梦是文学创作的一种特殊的表达方式。在小说《简爱》中,夏洛蒂.勃朗特通过梦的意象把女主人公简爱充满疑虑和矛盾的内心展现在读者面前。该文对小说中的梦境描写进行了归类并对其作了进一步分析,展示通过梦意象的运用产生了震撼人心的艺术效果,增强了思想感情表达的艺术张力。  相似文献   

后牙折裂原因与分类初探     

张李明  卢东民 《湖州师范学院学报》2004,26(2):95-97

收集典型病例，观察年龄、牙位、牙髓状况、充填洞型、咬合等与牙折裂的关系，按斜折、纵折、横折、粉碎折四型对牙折进行分类，研究发现：后牙折裂年龄集中在30～60岁，上下颌第一磨牙折裂率最高．折裂与牙髓状况、充填、咬合有关，各型牙折以Ⅰ类B型和Ⅱ类B型牙折率较高．死髓牙、严重磨耗牙、Ⅱ类洞充填的牙要特别注意防止其发生牙折，不同类型的牙折治疗原则应有针对性。  相似文献   

网络舆情信息受众的观点认知距离计量研究     

高俊峰  宋绍成 《图书情报工作》2016,60(20):77-85

[目的/意义] 量化展现网络舆情信息受众之间的观点认知距离与情感归属,澄清其情感倾向性的形成脉络,为科学应对群体性突发事件提供思路。[方法/过程] 切分舆情事项子话题,通过情感本体计算受众观点的极性强度,构建2-模的受众-关注焦点隶属矩阵和1-模的受众关系矩阵,并采用复杂网络可视化图谱对受众认知距离进行可视化展示,从网络舆情场的视角下阐述受众观点的互斥与耦合机制,描述受众情感倾向的形成脉络。[结果/结论] 对受众整体认知网络中不同类型的受众加以区分,揭示真实情景中的网络舆情场力的作用特点,为舆情受众情感疏导工作提供实践出发点。  相似文献