Document Type Profiles in Nature, Science, and PNAS： Journal and Country Level

Purpose： In this contribution, we want to detect the document type profiles of the three prestigious journals Nature, Science, and Proceedings of the National Academy of Sciences of the United States （PNAS） with regard to two levels： journal and country. Design/methodology/approach： Using relative values based on fractional counting, we investigate the distribution of publications across document types at both the journal and country level, and we use （cosine） document type profile similarity values to compare pairs of publication years within countries. Findings： Nature and Science mainly publish Editorial Material, Article, News Item and Letter, whereas the publications of PNAS are heavily concentrated on Article. The shares of Article for Nature and Science are decreasing slightly from 1999 to 2014, while the corresponding shares of Editorial Material are increasing. Most studied countries focus on Article and Letter in Nature, but on Letter in Science and PNAS. The document type profiles of some of the studied countries change to a relatively large extent over publication years. Research limitations： The main limitation of this research concerns the Web of Science classification of publications into document types. Since the analysis of the paper is based on document types of Web of Science, the classification in question is not free from errors, and the accuracy of the analysis might be affected.Practical implications： Results show that Nature and Science are quite diversified with regard to document types. In bibliometric assessments, where publications in Nature and Science play a role, other document types than Article and Review might therefore be taken into account. Originality/value： Results highlight the importance of other document types than Article and Review in Nature and Science. Large differences are also found when comparing the country document type profiles of the three journals with the corresponding profiles in all Web of Science journals.

Do Chinese and American contributions in top journals have an equal citation potential?

Purpose： We want to contribute to the evaluation of Chinese research, focusing on contributions in top journals. Design/methodology/approach： Using a Mann-Whitney test we investigate if contributions in Nature, Science or the Proceedings of the National Academy of Sciences of the United States of America （PNAS） by Chinese or American authors only, i.e. articles for which all authors have a Chinese or an American address, have a different citation potential. Findings： There is no reason to state that Chinese and American contributions in these top journals have a different citation potential. Research limitations： Because of the small numbers involved we were not able to make a distinction between publications in Nature, Science or the Proceedings of the National Academy of Sciences of the United States of America. Practical implications： These results suggest that the better Chinese research results are of a similar level as those by American colleagues. Originality/value： It is well-known that the number of citations per publication by Chinese authors is still lagging with respect to leading scientific nations and in particular compared with the USA. We have shown that this difference does not necessarily hold in contributions in Nature, Science or the Proceedings of the National Academy of Sciences of the United States of America.