Abstract

This chapter focuses on formal modelling. A formal model is the mathematical exposition of reasoning. Its purpose is to formulate consistent and rigorously stated hypotheses, which often shed light on the causation of a particular social phenomenon. Often, in the social sciences, a formal model is valuable because it can accurately predict behaviour and describe an actual (although unobservable) causal mechanism. Thus, formal models also allow plenty of space for deductive reasoning. Whether they clarify hypotheses or describe a mechanism, the success of formal models remains a matter of debate. The chapter then presents a few examples of useful models and considers the most frequent criticisms of formal modelling in order to identify a series of good practices for its proper use.