Much ado about nothing? : the wage effect of holding a Ph.D. degree but not a Ph.D. job position / Giuseppe Lucio Gaeta (University of Naples l'Orientale and c.MET05), Giuseppe Lubrano Lavadera (University of Salerno), Francesco Pastore (Seconda Università di Napoli and IZA) ; IZA. Bonn : IZA, July 2016