Boswort, StevenAlarfaj, Omar2025-10-012025https://hdl.handle.net/20.500.14154/76522This thesis examines investor behaviour in the Saudi stock markets (SSM), with a focus on various psychological and behavioural aspects such as the disposition effect, herd mentality, and investors' inclination toward Shariah-compliant investments. These three areas collectively examine the psychological and behavioural dimensions underlying market participants' regret aversion and fear of missing out within the context of the SSM including the associated market anomalies and behavioural biases. Following a brief introduction, the research findings that contribute to the existing literature are discussed and explored in Chapters 2, 3 and 4.239enBehavioural BiasProspect TheoryRegret Aversion TheoryHerd BehaviourBehavioural FinanceFinancial EconometricsFinancial Markets Modeling.Thesis