As a scientist he is mostly known for his solution to the Fallacy of Large Numbers (formulated by Paul A Samuelson in 1963) and his formulation of the Maslowian Portfolio Theory in the field of investment advice (and annex theory Target Oriented Investment Advice).
He is associated to the University of Warsaw and has a collaboration with the Vlerick Business School, while working in risk management for a large banking corporation.
Shares (that are much more risky) are typically advised if the investment horizon is longer (depending on the country culture this is between 3 and 15 years).
This seems to make sense, if one has 10K and wants to buy something of 10K on short term, investing in equities is risky as it would not be uncommon to lose 10% on such portfolio on a horizon of one year.
The last few hundred years of capitalist history learns us that on longer horizons the probability that equities have a negative return is much lower.
This paradigm is fundamental to all investment advice, but in 1963 Samuelson wrote a short paper arguing that it is not rational to compound a mistake or in other words that "unfairness can only breed unfairness", meaning that it is not rational to accept a series of bets when one would not accept one of the atomic bets (if one is a utility optimizer).
[3] The utility function has a kink in the actual wealth and decreases faster for losses than it increases for profits.
Adding this to the fact that all investors are loss averse,[4] this result is to be considered as an important step in responsible investment advice.
While theoretically appealing for its consistency and logical coherence, in practice it is not easy to estimate the parameter
This non-existent concept is the determined with the most primitive MCDA method, the Weighted sum model.
De Brouwer develops a theory "Target Oriented Investment Advice" that provides the mathematical framework.
Noteworthy is De Brouwer's effort to make help practitioners understand the concept and importance of coherent risk measure (see eg.
[21][22] Honorary consuls of Belgium are entrusted with the fiduciary care of wellbeing of Belgian nationals abroad and can be a first contact point in case with travel related or other problems.