For utility maximization problems under proportional transaction costs, it has been observed that the original market with transaction costs can sometimes be replaced by a frictionless shadow market that yields the same optimal strategy and utility. However, the question of whether or not this...

For utility maximization problems under proportional transaction costs, it has been observed that the original market with transaction costs can sometimes be replaced by a frictionless {\em shadow market} that yields the same optimal strategy and utility. However, the question of whether or not...

For utility maximization problems under proportional transaction costs, it has been observed that the original market with transaction costs can sometimes be replaced by a frictionless "shadow market" that yields the same optimal strategy and utility. However, the question of whether or not this...

For utility maximization problems under proportional transaction costs, it has been observed that the original market with transaction costs can sometimes be replaced by a frictionless {\em shadow market} that yields the same optimal strategy and utility. However, the question of whether or not...

For an investor with constant absolute risk aversion and a long horizon, who trades in amarket with constant investment opportunities and small proportional transaction costs, weobtain explicitly the optimal investment policy, its implied welfare, liquidity premium, andtrading volume. We...

In a market with one safe and one risky asset, an investor with a long horizon, constantinvestment opportunities, and constant relative risk aversion trades with small proportionaltransaction costs. We derive explicit formulas for the optimal investment policy, its impliedwelfare, liquidity...

Consider an investor trading dynamically to maximize expectedutility from terminal wealth. Our aim is to study the dependencebetween her risk aversion and the distribution of the optimal terminalpayo. Economic intuition suggests that high risk aversion leads to arather concentrated distribution,...

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...