1.5 Measurement Information Model
The Measurement Information Model described here is one of the fundamental concepts inherent to a successful, information-driven measurement program. The Measurement Information Model is a mechanism for linking defined information needs to the project software processesand products, the entities that can actually be measured. It establishes a defined structure for relating measurement concepts and, as such, provides a basis for accurately communicating measurement results within the organization.
The Measurement Information Model is a primary resource within the measurement process. It provides a structure that defines specific project measures and relates them to the needs of project decision makers. It provides a well-defined analysis path that supports recommendations derived from the analysis of the collected data. The Measurement Information Model directly supports both measurement planning and analysis activities.
Figure 1-1 Measurement Information Model relationships
In their most basic form, the relationships defined by the Measurement Information Model are depicted in Figure 1-1. During the planning and execution phases of a software project, technical and management decisions addressing many different areas must be made on a continuing basis. Decision makers must make trade-off decisions involving cost, schedule, capability, and quality. As a result, there is a definitive need for information to support the decision-making process. The Measurement Information Model helps to define the information needs of the project decision makers and focuses measurement planning activities on the selection and specification of the most appropriate software measures to address those needs. As the measures are implemented and data is collected, the Measurement Information Model helps to structure the measurement data and associated analysis into structured information products. These information products integrate the measurement results with established decision criteria and present recommendations to project decision makers on alternative courses of action.
In a typical software project, there are many information needs defined at any point in time. These information needs tend to change significantly during the course of the project, based on changing project objectives, assumptions, and constraints.
Chapter 2 fully describes the Measurement Information Model and all of its components.