Software comprehension: Theory and metrics

The understandability of a program specification has a direct bearing on several important aspects of software quality. These include reliability, modifiability, reusability, and maintainability to name a few.;The process of comprehension has been studied by psychologists. Their findings have implications for software engineering practises. A survey of pertinent studies in memory usage and comprehension processes reveals motivators for good software engineering practices.;Software metrics are used in software engineering to predict human performance, for instance faults per thousand lines of code. A survey of software metrics which are related to human performance is included. Recently proposed metrics are examined.;Rules for developing software that respect human limitations are derived based on psychological research and software engineering practises.;An empirical study of human performance against a newly proposed metric based on comprehension processes is done using the performance of students on final examinations. The metric, identifier density, is found to predict human error.