This dissertation studies the importance of shocks in understanding economic outcomes, both at the aggregate and at the individual levels. The research in this document is separated into chapters that deal with somewhat dissimilar questions which are linked by the necessity to acknowledge and understand how unforeseeable shocks determine how agents make economic decisions. These shocks or innovations are a potential explanation for why, often similar economic actors face very different paths. In Chapter 2, the interest lays in the determinants of different life-cycle fertility outcomes across educational groups. The chapter presents a model where individuals deal with idiosyncratic shocks in the f...