“…Thomas 1988;Finkelstein & Hambrick, 1996;Waldman & Yammarino, 1999;Mumford, Scott, Gaddis, & Strange, 2002;Bertrand & Schoar, 2003;Jones and Olken 2005;Yukl, 2008;Mackey, 2008;Goodall 2009a;Souder, Simsek & Johnson, 2012;Dezs & Ross, 2012;Nohe, Michaelis, Menges, Zhang, & Sonntag, 2013). To estimate leaders' effects in an exact way within real-world settings is known to be problematic (Antonakis, Bendahan, Jacquart, &Lalive, 2010, Blettner, Chaddad andBettis, 2012); it is not possible, outside a laboratory, to randomly assign a leader to an organization. In this area of social science, therefore, the discovery of persuasive conclusions has to rest, at least in large part, on the availability of error-free observational data and on truly consistent replication across a wide range of settings.…”