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...

This paper discusses the role of annuities in retirement planning. It begins by explaining the basic theory underlying the individual welfare gains available from annuitizing resources in retirement. It then contrasts these findings with the empirical findings that so few consumers behave in a...

This paper establishes a causal relation between an individual's decision of whether to own stocks and average stock market participation decision of the individual's community. We instrument for the average ownership of an individual's community with lagged average ownership of the states in...

Rational models of risk-averse consumers have difficulty explaining limited annuity demand. We posit that consumers evaluate annuity products using a narrow "investment frame" that focuses on risk and return, rather than a "consumption frame" that considers the consequences for lifelong...

This paper is the first to investigate the importance of geography in explaining equity market participation. We provide evidence to support two distinct local area effects. The first is a community ownership effect, that is, individuals are influenced by the investment behavior of members of...

This paper examines how the menu of investment options made available to workers in defined contribution plans influences portfolio choice. Using unique panel data of 401(k) plans in the U.S., we present three principle findings. First, we show that the share of investment options in a...

This paper provides new evidence on what types of individuals are most likely to choose a defined contribution (DC) plan over a defined benefit (DB) plan. Making use of administrative data from the State Universities Retirement System (SURS) of Illinois, we study the decisions of nearly 50,000...

This paper examines why some employers provide matching contributions to 401(k) plans in company stock and explores the implications of match policy for employee retirement wealth. Unlike stock option grants to non-executives, a firm's decision to match in company stock does not appear to be...

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)...