Impact of Special Collections in JGR Space Physics.

Journals occasionally solicit manuscripts for special collections, in which all papers are focused on a particular topic within the journal's scope. For the Journal of Geophysical Research: Space Physics, there have been 51 special collections from 2005 through 2018, with a total of 1,009 papers out of the 8,881 total papers in the journal over those years (11%). Taken together, the citations to special collection papers, as well as other metrics, are slightly higher than papers not in special collections. Several paper characteristics were examined to assess whether they could explain the higher citation and download values for special collection papers, but they cannot. In addition, indirect methods were conducted for assessing self‐citations as an explanation for the increased citations, but no evidence was found to support this hypothesis. It was found that some paper types, notably Commentaries and Technical Reports, have lower average citations but higher average downloads than Research Articles (the most common type of paper in this journal). This implies that such paper types have a different kind of impact than "regular" science‐result‐focused papers. In addition to having higher average citations and downloads, special collections focus community attention on that particular research topic, providing a deadline for manuscript submissions and a single webpage at which many related papers are listed. It is concluded that special collections are worth the extra community effort in organization, writing, and reviewing these papers. Plain Language Summary: Journals sometimes focus the attention of the research community by having a special collection, even an entire issue, devoted to a single topic. A reasonable question to ask is whether the extra effort of organizing, promoting, and maintaining the special collection is worthwhile. This paper examines paper impact in this journal, the Journal of Geophysical Research Space Physics, separating the special collection papers from those not in special collections. The short answer is, on average, yes, at least based on the metric of citations. Some characteristics of the paper were also assessed, such as the use of a colon in the title, the average author team size, the average number of references in each paper, and the paper type of the articles. None of these factors explains the higher average citations and downloads for papers in special collections. In this analysis, though, it was found that several paper types have lower‐than‐average citations but higher‐than‐average downloads, including Commentaries (personal perspectives articles) and Technical Reports (describing new methods or data sets). This implies that such papers are being read but perhaps not heavily referenced (yet). The overall conclusion is that special collections are worth the extra work. Key Points: JGR Space Physics published 51 special collections from 2006 to 2018, totaling 1,009 papers out of 8,881Average citations and downloads are slightly higher for papers in special collections compared to those not in collectionsPaper attributes thought to influence citations were analyzed, finding no statistically significant effect for special collection papers compared to others [ABSTRACT FROM AUTHOR]