Problem Oriented Software Engineering: Estimating Software Package Reliability by Determining Error Rate

Software packages play an important role in our lives. Products and services that affect people’s lives must have quality attributes. Therefore, good quality software package is required and in order to determine the quality of software package we need methods to measure it reliability. An interesting point here is that the quality of software may change over time and software package is no exception. In the early days of computing, software costs represented a small percentage of the overall cost of a computer-based system. Hence, a sizable error in estimates of software cost had relatively little impact. Today, software is the most expensive element in many computer-based systems. Therefore, steps taken to reduce the cost of software can make the difference between the profit and loss of a company. So, by determining the quality attributes of software, more precise, predictable and repeatable control over the software development process and product will be achieved. We propose a formal approach from the problem oriented software engineering point of view, for estimating the reliability of a software package by determining the error rate.