Many techniques have been developed for
measuring quality. In what follows, we survey the ones we are going to use in the
remainder of this chapter.
Goal.Question.Metric.(GQM).
GQM is a framework for metric definition (Basili et al., 1992). It defines a top-down
procedure allowing for specifying what is going to be measured, and to trace how
measuring must be performed, providing a framework for result interpretation. The
outcome of the process is the specification of a system of measurements that consists
of a set of results and a set of rules for the interpretation of the collected data.
The model defines three levels of analysis: (a) conceptual (Goal), where a goal for
a product, process, or resource is defined; (b) operational (Question): at this level,
a set of questions is used for describing the way a specific goal will be reached; and
(c) quantitative (Metric): the metric associated with each question. The model is a
hierarchical structure that starts from a goal, follows with a set of questions refining
the goal, and ends with the metrics that will help answer the questions. For example,
if our goal consists in measuring the legibility of a certain text, the question would
be ???what is the level of readers??™ comprehension???? The metric will be the number
of readers who understood the text.
Data Quality-Based Requirements Elicitation for Decision Support Systems 6
Copyright ?© 2007, Idea Group Inc.
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