Software metrics: good, bad and missing

The software industry is an embarrassment when it comes to measurement and metrics. Many software managers and practitioners, including tenured academics in software engineering and computer science, seem to know little or nothing about these topics. Many of the measurements found in the software literature are not used with enough precision to replicate the author´s findings-a canon of scientific writing in other fields. Several of the most widely used software metrics have been proved unworkable, yet they continue to show up in books, encyclopedias, and refereed journals. So long as these invalid metrics are used carelessly, there can be no true software engineering, only a kind of amateurish craft that uses rough approximations instead of precise measurement. The paper considers three significant and widely used software metrics that are invalid under various conditions: lines of code or LOC metrics, software science or Halstead metrics, and the cost-per-defect metric. Fortunately, two metrics that actually generate useful information-complexity metrics and function-point metrics-are growing in use and importance.<>