A model based on software quality factors which predicts maintainability

Software quality metric were developed to measure the complexity of software systems. The authors relate the complexity of the system as measured by software metrics to the amount of maintenance necessary to that system. The authors have developed a model which uses several software quality metrics as parameters to predict maintenance activity. A description is given of three classifications of metrics that are used to measure the quality of source code: code metrics, which measure physical characteristics of the software, such as length or number of tokens; structure metrics, which measure the connectivity of the software, such as the flow of information through the program and flow of control; and hybrid metrics, which are a combination of code and structure metrics