Biases at the Bank : Gender Differences in Behavioural Biases among UK Investment Bankers

This study examines gender differences in behavioural biases among UK investment bankers, a professional group rarely explored in behavioural finance research. Using an online survey of 72 bankers, we assess four cognitive biases – overconfidence, herding, loss aversion and overreaction – through the lenses of prospect theory and heuristics theory. The results show that males exhibit significantly higher overconfidence, while no meaningful gender differences emerge for herding, loss aversion or overreaction, suggesting that professional expertise may moderate commonly observed disparities. Additional analysis reveals that herding decreases with age among female bankers, indicating a gender specific demographic influence. Further, inter-bias relationships differ across genders: males show a strong negative association between overconfidence and loss aversion, whereas females display a positive link between herding and overreaction. Overall, the findings highlight that cognitive biases persist even in sophisticated professional settings, offering implications for risk management, training and the design of diverse decision making teams.