The “statistical discrimination” theory maintains that discrimination is based on stereotypes: in a context of information asymmetries, employers use an observable identity characteristic of a group (e.g. race or gender) as a signal for an unobservable variable (e.g. skills or productivity) (Phelps, 1972, Arrow, 1973). From early age, boys and girls perceive different stereotyped notions of what they should excel and enjoy in doing, which shapes their behaviours and may even affect their performance (Hill, Corbett and St. Rose, 2010, OECD, 2012a). For example, as early as the first year of primaiy school, girls rate their own ability in mathematics as lower than that of boys, even when their actual performance does not differ (Fredericks and Eccles, 2002, Herbert and Stipek, 2005).