DERIVING STRUCTURALLY BASED SOFTWARE MEASURES

Many software engineering methods place internal structural constraints on the documents (including specifications, designs, and code) that are produced. Examples of such structural constraints are low coupling, high cohesion, reuse in designs and code, and control structuredness and data-abstraction in code. The use of these methods is supposed to increase the likelihood that the resulting software will have desirable external attributes, like reliability and maintainability. For this reason, we believe that the software engineering community needs to know how to measure internal attributes and needs to understand the relationships between internal and external software attributes. This can only be done if we have rigorous measures of the supposedly key internal attributes. We believe that measurement theory provides an appropriate basis for defining such measures. By way of example, we show how it is used to define a measure of coupling. © 1990.