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UCD Description for SWUIWiki "How To" section

From: Roberto García <rogargon@gmail.com>
Date: Thu, 31 May 2007 22:26:44 +0200
Message-ID: <e56f135c0705311326o1886c6c2q3e2fa3119d2599d9@mail.gmail.com>
To: public-semweb-ui@w3.org
Dear all,

Before adding the following text to the "How To" section of the
SWUIWiki, I would appreciate your comments about the following
description of User Centred Design (UCD). Do you think it is


User-Centred Design

The methodology for developing usable and accessible applications is
called User-Centred Design (UCD). It is based on an iterative
development process based on a detailed study of the users' needs, the
tasks they carry on in order to meet them and the context in which
they are performed (Norman 1986). There are many UCD development
processes proposals, but all of them provide a mix of software
engineering plus usability and accessibility engineering tasks. One
particular proposal, which combines both disciplines in a neat way
thus facilitating its adoption, is the usability and accessibility
Engineering Process Model (MPIu+a) sketched in Figure 1 (Granollers


Fig. 1. Usability and accessibility Engineering Process Model (MPIu+a)

This UCD proposal, as other software development processes, starts
with the requirements gathering phase. However, the emphasis is placed
on users. First of all, it is important to know who the users are.
Then, the following step is to identify the tasks they are going to

The development process continues with the common phases, i.e. design,
implementation and deployment. Despite these similarities, the focus
continues to be placed on the user.

In order to keep user needs present during the whole development
process, the previous phases are complemented with two additional ones
that are performed in parallel, for each process iteration,
prototyping and evaluation.

Prototypes are created from the beginning, for instance paper
prototypes (Snyder 2003), which do not require any implementation, or
simple applications with limited functionality. All of them are used
to evaluate the system with users so their requirements are taken into
account and contrasted with the developed system just from the
beginning and through all the development process iterations.

Once developed, prototypes are tested with users and experts in the
evaluation phase. There are three kinds of evaluation methods:

- Inspection: these evaluation methodologies are performed by experts,
the evaluators, that inspect the usability and accessibility aspects
of the system based on a set of guidelines, e.g. heuristic usability
evaluations and walkthroughs (Nielsen 1994).

- Inquiry: the objective is to draw usability conclusions from
observing and talking with users. There are surveys, interviews, field
observations, focus groups, logs analysis, etc.

- Test: they are performed in a controlled environment, usually a
usability laboratory, where specialised software applications are used
to record and analyse the whole interaction, i.e. screen capture, key
strokes, mouse clicks, user video record and voice,... while
representative users interact with the system or a prototype.

D. Norman and S. Draper: "User-centered systems design: new
perspectives on human-computer interaction". Lawrence Erlbaum, 1986
T. Granollers: "User Centred Design Process Model. Integration of
Usability Engineering and Software Engineering". Doctoral Consortium,
INTERACT 2003, Zurich, 2003
J. Nielsen and R. L. Mack (eds.): "Usability Inspection Methods". John
Wiley & Sons, New York, 1994
C. Snyder: "Paper Prototyping: The Fast and Easy Way to Design and
Refine User Interfaces". Morgan Kaufmann, 2003

Roberto García

(image/png attachment: mpiua.png)

Received on Thursday, 31 May 2007 20:27:01 GMT

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