“…the players' skills and abilities. The ex-post inputs in sports economics literature used to be: sports statistics, e.g., shots, in soccer; rebounds, in basketball; batting, in baseball (Carmichael et al, 2000;Sexton and Lewis, 2003;Espitia-Escuer and García-Cebrián, 2006;Boscá et al, 2009;Tiedemann et al, 2011;Moreno and Lozano, 2012;and Zambom-Ferraresi et al, 2015); or wages/salaries (Haas, 2003;Frick and Simmons, 2008;Ribeiro and Lima, 2012). These ex-post inputs are employed to analyse the second stage of PF where intermediate inputs (Z) produced output (Y).…”