Level 4 - The Managed Level

At the Managed Level, the organization sets quantitative quality goals for both software products and processes. Productivity and quality are measured for important software process activities across all projects as part of an organizational measurement program. An organization-wide software process database is used to collect and analyze the data available from the projects' defined software processes. Software processes are instrumented with well-defined and consistent measurements at Level 4. These measurements establish the quantitative foundation for evaluating the projects' software processes and products.

Projects achieve control over their products and processes by narrowing the variation in their process performance to fall within acceptable quantitative boundaries. Meaningful variations in process performance can be distinguished from random variation (noise), particularly within established product lines. The risks involved in moving up the learning curve of a new application domain are known and carefully managed.

The software process capability of Level 4 organizations can be summarized as predictable because the process is measured and operates within measurable limits. This level of process capability allows an organization to predict trends in process and product quality within the quantitative bounds of these limits. When these limits are exceeded, action is taken to correct the situation. Software products are of predictably high quality.

Level Four processes

        Quantitative Process Management

Measurements are taken of process performance and a procedure defines what measurements are to be collected, how they will be used, and how they will be analysed etc.  Measurement are chosen from all life cycle activities of all project across the organisation.  Measurements collected should be a natural result of software activities where possible.  Measurements are stored in the organisations software process database.

Quality Management

Software quality management addresses the quality of the software product.  The activities for the software quality management are planned.  Goals are defined for the quality of software products.  Progress towards the achievements of these goals is monitored.  Input to software quality goals comes from the customer, the end user and the organisations strategic quality plans.  Examples of quality may be to find a pre-determined number if errors during a test cycle.