This study investigated the evolution of library and information science (LIS) by analyzing research topics in LIS journal articles. The analysis is divided into five periods covering the years 1996–2019. Latent Dirichlet allocation modeling was used to identify underlying topics based on 14,035 documents. An improved data-selection method was devised in order to generate a dynamic journal list that included influential journals for each period. Results indicate that (a) library science has become less prevalent over time, as there are no top topic clusters relevant to library issues since the period 2000–2005; (b) bibliometrics, especially citation analysis, is highly stable across periods, as reflected by the stable subclusters and consistent keywords; and (c) information retrieval has consistently been the dominant domain with interests gradually shifting to model-based text processing. Information seeking and behavior is also a stable field that tends to be dispersed among various topics rather than presented as its own subject. Information systems and organizational activities have been continuously discussed and have developed a closer relationship with e-commerce. Topics that occurred only once have undergone a change of technological context from the networks and Internet to social media and mobile applications.

中文翻译：

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1996-2019年LIS研究主题的演变：基于潜在Dirichlet分配主题模型的分析

本研究通过分析 LIS 期刊文章中的研究主题，调查了图书馆和信息科学 (LIS) 的演变。分析分为五个时期，涵盖 1996-2019 年。潜在狄利克雷分配模型用于识别基于 14,035 个文档的潜在主题。为了生成包含每个时期有影响力的期刊的动态期刊列表，设计了一种改进的数据选择方法。结果表明 (a) 图书馆科学随着时间的推移变得不那么流行，因为自 2000-2005 年以来没有与图书馆问题相关的热门主题集群；(b) 文献计量学，尤其是引文分析，在各个时期都非常稳定，这体现在稳定的子群和一致的关键词上；(c) 信息检索一直是主导领域，兴趣逐渐转移到基于模型的文本处理。信息寻求和行为也是一个稳定的领域，往往分散在各种主题中，而不是作为自己的主题呈现。信息系统和组织活动不断被讨论，并与电子商务建立了更密切的关系。只发生过一次的话题经历了从网络和互联网到社交媒体和移动应用程序的技术背景的变化。信息系统和组织活动不断被讨论，并与电子商务建立了更密切的关系。只发生过一次的话题经历了从网络和互联网到社交媒体和移动应用程序的技术背景的变化。信息系统和组织活动不断被讨论，并与电子商务建立了更密切的关系。只发生过一次的话题经历了从网络和互联网到社交媒体和移动应用程序的技术背景的变化。