Select the Subprocesses that Will Be Statistically Managed

Selecting the subprocesses to be statistically managed is often a concurrent and iterative process of identifying applicable project and organization quality and process-performance objectives, selecting the subprocesses, and identifying the process and product attributes to measure and control. Often the selection of a process, quality and process-performance objective, or measurable attribute will constrain the selection of the other two. For example, if a particular process is selected, the measurable attributes and quality and process performance objectives may be constrained by that process.

• Identify which of the quality and process-performance objectives of the project will be statistically managed.
• Identify the criteria to be used in selecting the subprocesses that are the main contributors to achieving the identified quality and process-performance objectives and for which predictable performance is important. Examples of sources for criteria used in selecting subprocesses include:
  • Customer requirements related to quality and process performance
  • Quality and process-performance objectives established by the customer
  • Quality and process-performance objectives established by the organization
  • Organization’s performance baselines and models
  • Stable performance of the subprocess on other projects
  • Laws and regulations
• Select the subprocesses that will be statistically managed using the selection criteria. It may not be possible to statistically manage some subprocesses (e.g., where new subprocesses and technologies are being piloted). In other cases, it may not be economically justifiable to apply statistical techniques to certain subprocesses.
• Identify the product and process attributes of the selected subprocesses that will be measured and controlled. Examples of product and process attributes include:
  • Defect density
  • Cycle time
  • Test coverage