Structures de financement et instabilités endogènes

According to H. P. Minsky?s Financial Instability Hypothesis [1975], [1986], the endogenous deterioration of financial structures during growth phases generates endogenous dynamics. The traditional interpretation of Minsky?s analysis ascribes the origin of this process to irrational behaviours, as banks satisfy business?s external financing demand whereas debt ratios are high. We develop a model conveying the financial instability mechanism while at the same time taking into account a certain type of bank rationality. In fact, capital accumulation dynamics integrate a financial constraint similar to the one developed in financial accelerator models (Bernanke et Gertler [1989], [1990]). Financing costs are given by an endogenous external finance premium inversely related to debt ratios. Stability crucially depends on the level of agency costs and of debt ratios. Moreover, via a Hopf bifurcation, the external finance premium can generate cyclical endogenous dynamics. Classification JEL: G3, E32, E51