This paper examines the impact of superstitious beliefs on human capital accumulation, focusing on the Italian fear of Friday the 17th. Using administrative records covering more than 1.7 million university exams from 2002 to 2023, we document a systematic performance penalty when exams are held on this culturally salient date. Students score significantly lower on Friday the 17th compared to other days, even after controlling for a rich set of fixed effects and covariates. To identify superstition as the underlying mechanism, we construct individual-level superstition indices by combining the European Values Study with an original survey administered at the University of Modena and Reggio Emilia. The results reveal that the negative effect is entirely driven by students with a higher predicted propensity to be superstitious, while it vanishes among less superstitious individuals. Robustness checks and placebo tests rule out alternative explanations such as exam difficulty or student selection. Our findings highlight how cultural beliefs can act as exogenous cognitive frictions, reducing educational performance and potentially widening socioeconomic inequalities.
Co-authors: Giovanni Gallo, Anthony Lepinteur
