Mohammadnejadaghdam, Ali, Fazlzadeh, Alireza, Ahmadian, Vahid, Naghdi, Sajad (2022). Improving the performance of Fama - French models in predicting expected returns by offering new definitions of risk factors in the Tehran stock exchange. *Advances in Finance and Investment*, 3(9), 29-52. 10.30495/afi.2023.1972376.1171