Market imperfections and endogenous fluctuations : on the role of externalities in preferences and financial constraints.

Summary Based on the endogenous cycle theory, this doctoral thesis studies the issue of macroeconomic instability and endogenous fluctuations in three distinct economies: I) with external effects in consumption in a Ramsey model. II) with externalities in leisure in a nested generations model. and III) with credit market imperfections in a monetary endogenous growth model.