Examining the most heavily-cited publications in labor economics from the early 1990s, I show that few of over 3000 articles citing them directly replicates them. They are replicated more frequently using data from other time periods and economies, so that the validity of their central ideas has...

The way the fields are delineated has been the Achilles' heel of studies analyzing the status and evolution of given scientific areas. Based on van den Besselaar and Leydesdorff's (Mapping change in scientific specialities; a scientometric reconstruction of the development of artificial...