Mistakes made in the decision-making process in the light of behavioural financial economics

For a long time, the ability of people to rationally – in accordance with the concept of homo oeconomicus – carry out decision-making processes under conditions of uncertainty was not questioned, thanks to the observation of frequent errors made in decision-making processes – systematic deviations from the pattern set by the normative theory of expected utility, led Kahneman and Tversky to develop a descriptive prospect theory, which, by taking into account psychological aspects, more accurately reflects the actual behaviour of individuals. The survey carried out verifies the existence of flaws in the assumptions about rationality in classical finance theory, and the influence of psychological aspects on the actual behaviour of decision-makers in the decision-making process.