What is the difference of research collaboration network under different projections: Topological measurement and analysis

•We construct the author collaboration networks by three different projections.•We measure and analyze the topological feature of these three different author collaborations.•Different projections have distinct influence on degree distribution, shortest path length and clustering coefficient.•Different projections have no significant influence on connected subgraphs, betweenness and degree correlation coefficient.

Research collaboration network is a typical bipartite network that consists of papers and authors. This bipartite network could be transformed into one-mode networks by projection. In this paper, we used three different projections to construct three co-authorship networks. Topological features of three co-authorship networks are measured and analyzed in order to understand the influence of projections on network features. The measurement results show that different projections could lead to different topological features. Therefore, to reflect the existing reality more precisely, projection method is suggested to be considered when we investigate the structure of scientific collaborations and/or assess the status, impact and influence of researchers and their institutions.