Assumptions

Financial economics is based on several assumptions - chief amongst these, that financial decision makers are rational. However, recently, researchers in Experimental economics and Experimental finance have challenged this assumption empirically. Further, these assumptions are challenged - theoretically - by Behavioral finance, a discipline primarily concerned with the rationality, or lack thereof, of economic agents.




Other common assumptions include market prices following a random walk, or asset returns being normally distributed. Empirical evidence suggests that these assumptions may not hold, and in practice, traders and analysts, and particularly risk managers, frequently modify the "standard models".