It is a matter of debate whether a shrinking proportion of scholarly literature is getting most of the references over time. It is also less well understood how a narrowing literature usage would affect the circulation of ideas in the sciences. Here we show, that the utilization of scientific literature follows dual tendencies over time: while a larger proportion of literature is cited at least a few times, citations are also concentrating more on the top of the citation distribution. Parallel to the latter trend, a paper's future importance increasingly depends on its past citation performance. A random network model shows that the citation concentration is directly related to the greater stability of citation performance. The presented evidence suggests that the growing heterogeneity of citation impact restricts the mobility of research articles that do not gain attention early on. While concentration grows from the beginning of the studied period in 1970, citation dispersion manifest itself significantly only from the mid-1990s when the popularity of freshly published papers has also risen. Most likely, advanced information technologies to disseminate papers are behind both of these latter trends.
翻译:一个争论的问题是,随着时间的流逝,学术文献比例的减少是否正在获得大部分参考文献。同样不甚清楚的是,日益缩小的文献使用会如何影响科学思想的传播。我们在这里表明,科学文献的利用随着时间的流逝而出现双重趋势:虽然引用的文献比例至少增加了几次,但引文也更多地集中在引文发行的顶端。与后一种趋势平行的是,文件的未来重要性越来越取决于其过去引用的性能。随机网络模型显示,引用的集中性与引文表现的更大稳定性直接相关。所展示的证据表明,引文影响日益多样化限制了研究文章的流动性,而这些研究文章没有在早期引起注意。虽然从1970年研究期开始,集中程度不断提高,但引文的分散性只是在1990年代中期才明显显现出来,当时新出版的论文的受欢迎程度也在上升。传播论文的先进信息技术很可能落后于后两种趋势。