In this thesis we deal with different topics in financial mathematics, that are all related to market imperfections and to the fundamental technique of utility maximization. The work consists of three parts. In the first one, which is based on two papers, we consider the problem of optimal...

Acteurs incontournables des marchés financiers, les hedge funds demeurent mal connus. Qui sont-ils ? Quelles sont leur techniques de gestion ? Qu'offrent-ils de différent en termes de performance et de risque ?

In this thesis we explore two recent topics in behavioral finance, namely portfolio optimization by non-expected utility insiders and existence of equilibria in financial markets populated by heterogeneous agents. Firstly, we review a number of theories which have been used to model behavioral...

In this paper we deal with a utility maximization problem at finite horizon on a continuous-time market with conical (and time varying) constraints (particularly suited to model a currency market with proportional transaction costs). In particular, we extend the results in Campi and Owen (2011)...

Hedge fund replication based on factor models is encountering growing interest. In this paper, we investigate the implications of substituting standard rolling windows regressions, which appear ad-hoc, with more effcient methodologies like the Kalman flter. We show that the copycats constructed...

Minimum variance and equally-weighted portfolios have recently prompted great interest both from academic researchers and market practitioners, as their construction does not rely on expected average returns and is therefore assumed to be robust. In this paper, we consider a related approach,...

Alternative assets are gaining increasing importance in investors' portfolios. One of their defining characteristic is their poor liquidity, which often translates into an inherent smoothing process of the returns. For asset allocation purposes, this feature has to be seriously addressed as it...

In this article, we characterize efficient portfolios, i.e. portfolios which are optimal for at least one rational agent, in a very general financial market model with proportional transaction costs. In our setting, transaction costs may be random, time-dependent, have jumps and the preferences...

We present an optimal investment theorem for a currency exchange model with random and possibly discontinuous proportional transaction costs. The investor’s preferences are represented by a smooth, multivariate utility function, allowing for simultaneous consumption of any prescribed selection...