2017PASP..129b4008A

I explore whether small or large teams produce the most important astronomical results, on average, using citation counts as our metric. I present evidence that citation counts indicate the importance of papers. For the 1343 papers published in A&A, ApJ, and MNRAS in 2012 January-February, I considered 4.5 years worth of citations. In each journal, there are larger citation counts for papers from large teams than from small teams by a factor of about 2. To check whether the results from 2012 were unusual, I collected data from 2013 for A&A and found it to be the same as that for 2012. Could the preponderance of papers by large teams be due to self-citations (i.e., citing and cited papers sharing one or more authors)? To answer this, I looked at 136 papers with one to 266 authors and discovered a linear relation that ranges from a 12.7% self-citation rate for single-author papers to a 45.9% self-citation rate for papers with 100 authors. Correcting for these factors is not enough to explain the predominance of the papers with large teams. Then I computed citations per author. While large teams average more citations than small ones by a factor of 2, individuals on small teams average more citations than individuals on large teams by a factor of 6. The papers by large teams often have far more data, but those by small teams tend to discuss basic physical processes.