A framework for defining coupling metrics

The paper describes a model of coupling that uses the reification of the concept of dependency as its fundamental unit. Based on this model, it defines a framework for defining coupling metrics. It shows how to define several well-known coupling metrics in the framework, and how defining different metrics based on the same model facilitates direct comparisons. It discusses how the framework resolves issues due to incomplete metric definitions, such as different language features. This formal framework is sufficiently simple that it can be implemented in such a way as to provide multiple metrics.