Reaching an
Agreement on COTS Quality through the
Use of Quality Models
It
is difficult to reach to an agreement on how to measure software
quality. It
has been argued that one of the reasons for this is that quality is a
complex
concept, for which a universal definition does not exist. Quality means
different things to different people, thus it is highly subjective and
context-dependant.
Kitchenham stated that quality is “hard to define, impossible
to
measure, easy to recognize”. Gilles stated quality is "generally
transparent when present, but easily recognized in its absence". Both
of
these statements imply that quality is somehow perceptible. Thus, the
problem
is not quality being subjective, but how to correlate the different
views on
quality into a measurable quality framework, which can be commonly
agreeable at
least in some context (e.g., a domain of knowledge, an organization, a
project,
etc.).Software quality models help in
this purpose: they can be used as a base to define a commonly agreeable
quality
framework, which consolidates the different views on quality; they can
be
tailored to specific contexts; they provide a measurable base to the
evaluation
of software quality. However, several problems remain which let quality
models to be used or misused in
the practice. In this paper we review these
problems and propose a set of characteristics which provide the basis
for the
construction of well founded and useful quality models. We focus our
analysis
in the context of COTS components.