Market imperfections and macroeconomic instability.

Summary In this thesis, we study the effect of market imperfections on macroeconomic stability in the standard Ramsey and OLG models. To carry out this objective, we use the method of local dynamics analysis introduced by Grandmont, Pintus and De Vilder (1998). The imperfections we use are externalities in consumption, imperfections in the credit market, the presence of a progressive tax on wage income and the existence of transaction costs associated with capital accumulation.