Information Technology Reference
In-Depth Information
The purpose of the case study is to show the feasibility of applying WUEP to dis-
cover usability problems at different levels of abstraction of a MDWD process. The
conceptual framework that links the phenomena to be studied is the idea based on
integrating usability evaluations into MDWD processes [11]. The research questions
that are intended to be addressed are:
a) What type of usability problems can be de-
tected in each phase of a model-driven Web development process and what are their
implications for intermediate artifacts (models)?
, and
b) What limitations does the
Web Usability Evaluation Process present?
.
The sampling strategy of the case study is based on an embedded single-case de-
sign. We contacted a Web development company located in Alicante (Spain) in order
to apply WUEP to a real Web application from a project in progress. The company
provided us with access to a task management system. The aim was to perform
evaluations on the artifacts that define this Web application at different abstraction
levels in an MDWD process.
WUEP was applied as follows: two of the authors performed the evaluation
designer role in order to design an evaluation plan (in critical activities such as the
selection of usability attributes, we required the help of two external Web usability
experts); and the evaluator role was performed by five evaluators: the other author
and four other independent evaluators with an average of five years' experience in
usability evaluations. The technique that was used to obtain feedback about the feasi-
bility of WUEP was the analysis of the usability reports and observation of the
evaluators when performing the execution of the evaluation. We have not considered
the
analysis of changes
stage since the aim of this case study was to show the feasibil-
ity of WUEP in discovering usability problems.
4.2 Preparation of the Case Study
An evaluation plan was defined by following WUEP. With regard to the
establish-
ment of evaluation requirements
stage of WUEP, the purpose of the evaluation was to
perform a usability evaluation during the development of the Web application men-
tioned above. The type of Web application was an Intranet that was developed using
the OO-H method [13] supported by the VisualWade tool (
www.visualwade.com
).
The context in which the Web application will be used is a software development
company, and there are two kinds of users: project manager and programmers.
OO-H is an MDWD method that provides the semantics and notation for develop-
ing Web applications. The platform-independent models (PIMs) that represent the
different concerns of a Web application are: a class model, a navigational model, and
a presentation model. The class model is UML-based and specifies the content re-
quirements; the navigational model is composed of a set of Navigational Access Dia-
grams (NADs) that specify the functional requirements in terms of navigational needs
and users' actions; and the presentation model
is composed of a set of Abstract Pres-
entation Diagrams (APDs), whose initial version is obtained by merging the former
models, which are then refined in order to represent the visual properties of the final
UI. The platform-specific models (PSMs) are embedded into a model compiler, which
automatically obtains the source code (CM) from the Web application by taking all
the previous PIMs as input.
