Every scientific journal has an impact factor, a metric that calculates the average number of times, in previous years, the research published in a particular journal was cited by other studies. In other words, how often does the average study from PLOS go on to inspire or otherwise support research by other scientists? It wasn't originally intended to be, but impact factor has grown into a surrogate measure of the quality of scholarship, says Randy Schekman, cell biologist at the University of California at Berkeley. Publishing in journals like Nature, or the New England Journal of Medicine, is seen as indication that a piece of research is particularly excellent. Getting multiple papers into those journals is seen as one of the best ways to build a reputation as a scientist, and get grant funding and academic jobs.