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User Interface Design CIS 322

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           Methods for
       user-centered design
Participatory Design:
The now widely recognised idea to involve the
users in the development of a system for
improved usability of the interface.
This is typically successful because users can
give designers their own opinions and make
useful suggestions, which can help to prevent
errors in the first place before they occur.
            Methods for
        user-centered design
             continued
Participatory Design continued:
The design should be able to anticipate
potential problems by interacting with users
during the design phase.
This has led to a design that makes erroneous
choices unavailable (greying out menu choices
or buttons if they are not available, e.g. if you
haven’t copied anything, you cannot paste).
           Methods for
       user-centered design
            continued
Participatory Design continued:
The design should attempt a good compromise
for both new and experienced users.
Therefore, both novices and experts should be
involved during the design phase of new
applications.
            Methods for
        user-centered design
             continued
Different Methods for user-centered design:


1. Soft Systems Methodology
2. Cooperative Design
3. Multiview
4. The star life cycle
           Methods for
       user-centered design
            continued
1. Soft Systems Methodology
Many HCI researchers consider a holistic point
of view as necessary. This means that is is
important to understand the whole human-
computer system and to put it into a wider
context, e.g. many human actions depend on
the situations humans currently experience.
            Methods for
        user-centered design
             continued
1. Soft Systems Methodology continued
One of the most popular holistic point of views
was given the name “Soft Systems
Methodology” (Checkland, 1981).
The idea of the Soft Systems Methodology is to
understand the particular situation in which the
problem is believed to lie and not to just find a
general solution to a specified problem.
            Methods for
        user-centered design
             continued
1. Soft Systems Methodology continued
Therefore, this approach first tries to define the
situation (stages 1 and 2). The definition of the
situation occurs in 2 stages. First, a problem
situation is perceived and in stage 2, a better
overview is gained by having the problem
situation expressed through communication
with all involved parties.
            Methods for
        user-centered design
             continued
1. Soft Systems Methodology continued
After expressing the problem in the given
situation, the approach tries to deliver a precise
definition (“root definition”) of the system (stage
3), which is applied to produce conceptual
models (=abstract representations) of the
system.
            Methods for
        user-centered design
             continued
1. Soft Systems Methodology continued
These conceptual models in stage 4 include
the consideration of clients/customers, actors,
transformations, world view, owners and the
environment. The precise root definition from
stage 3 will have already identified who all the
involved people are (i.e. the clients, the actors
who use the system and the owners of the
system).
            Methods for
        user-centered design
             continued
1. Soft Systems Methodology continued
Stages 3 and 4 are typically abstract modeling
processes that do not relate directly to the
specific situation at hand, i.e. many scenarios
can be considered and simulated. This is an
abstract modeling process that does not take
place in the real world (though the people from
the problem definition in stage 3 are real).
            Methods for
        user-centered design
             continued
1. Soft Systems Methodology continued
Stages 5, 6 and 7 then go away from the
abstract point of view and try to embed the
earlier processes into the real world (the
concrete situation at hand).
Stage 5 will expose gaps in the original root
definition after incorporating the expressed
situational circumstances until a well-formed...
            Methods for
        user-centered design
             continued
1. Soft Systems Methodology continued
...root definition has been found.
In Stage 6, the conceptual model of the
situation is compared with the original
expression of the situation (= the situation
before communication took place between all
involved parties and before the situation was
expressed through this communication).
            Methods for
        user-centered design
             continued
1. Soft Systems Methodology continued
it is possible that Stage 6 exposes further
changes that might be necessary.
In Stage 7, action takes place to improve the
situation at hand with the help of the designed
system, but this may not succeed in the first
place, so many iterations might be necessary.
             Methods for
         user-centered design
              continued
1. Soft Systems Methodology continued
Soft Systems Methodology has been highly
influential. Applied to designing HCI systems and
good user interfaces, the main focus is on combining
the actual purpose, the people involved, the technical
and human constraints, the world view of the people.
This helps to develop adequate conceptual models of
all involved people and system components so that
the goals of delivering a good system can be
achieved.
           Methods for
       user-centered design
            continued
2. Co-operative Design


...involves several approaches. They all have
in common that users participate in the design
process.
             Methods for
         user-centered design
              continued
2. Co-operative Design continued
I will refer to 3 (overlapping) approaches:


1. Participatory design (=Scandinavian Approach)
2. Socio-technical design
3. Open System Task Analysis (OSTA)
           Methods for
       user-centered design
            continued
2. Cooperative Design continued


Participatory Design aims to improve the
working conditions and the working
environment of the user. It involves full
collaboration with users and repeated
prototyping, workshops, etc.
            Methods for
        user-centered design
             continued
2. Co-operative Design continued


Participatory Design involves participation of
the user in analysing organisational
requirements and planning social as well as
technical structures that would benefit both the
employee and the organisation.
             Methods for
         user-centered design
              continued
2. Co-operative Design continued


The advantage of Participatory Design is that
it is likely to produce a workable and usable
system for all its users. The disadvantage is
that it is often difficult to control the cost of this
approach and that it requires some time to
implement in a satisfactory way.
            Methods for
        user-centered design
             continued
2. Co-operative Design continued
Socio-technical Design focuses on the entire
human-computer system and aims to find
designs that are both socially and technically
feasible. This is a difficult problem, because
this involves many elements (e.g. the different
models of tasks, domains and systems that
users and designers deal with).
           Methods for
       user-centered design
            continued
2. Co-operative Design continued
In order to deal with these difficulties of
incorporating all these elements, Socio-
technical Design focuses on a wide range of
methodologies for system design, analysis and
design techniques and evaluation methods.
           Methods for
       user-centered design
            continued
2. Co-operative Design continued
One example of a methodology that is based
on a socio-technical design is the Open
System Task Analysis (OSTA).
The aim of OSTA is to deliver a methodology
that helps understand what transformation
occurs when a new computer system is
introduced into a working environment.
           Methods for
       user-centered design
            continued
2. Co-operative Design continued
In summary, co-operative design approaches
involve users to actively participate in the
design process.
In order to avoid problems when relying on Co-
operative Design approaches, a number of
suggestions have been made.
             Methods for
         user-centered design
              continued
2. Co-operative Design continued
One suggestion is to rely on expert advice during the
design process, because experts have long
experience which helps them guide the design
process and support users.
Another suggestion is to only rely on co-operative
design if the management is committed to involve
users and to accept their requirements.
           Methods for
       user-centered design
            continued
2. Co-operative Design continued


Another problem that has been pointed out is
that none of these methods inform designers
how they can involve users.
            Methods for
        user-centered design
             continued
3. Multiview


...is an information systems design
methodology that combines the approaches
from soft systems methodology and co-
operative design into a staged and controlled
methodology (i.e. it defines an order of steps
that need to be carried out).
            Methods for
        user-centered design
             continued
3. Multiview continued


Multiview begins with an analysis of human
activities. This results in the Primary Task
Model (PTM). Furthermore, a conceptual
model is developed. After all this has taken
place, decisions about the actual design
implementation are made.
            Methods for
        user-centered design
             continued
3. Multiview continued


Consequently, Multiview provides more
direction for system designers by referring to
the different steps in the design process.
Multiview is a complete methodology and
spans from the planning of the design to its
actual implementation.
           Methods for
       user-centered design
            continued
4. The Star Life Cycle
The Star Life Cycle is based on the actual
design practice of User Interface Design
practitioners. In contrast to the structured
Mulitiview methodology, the Star Life Cycle
assumes that ordering of activities and
processes is inappropriate to User Interface
Design.
           Methods for
       user-centered design
            continued
4. The Star Life Cycle continued


Hence, the Star Life Cycle expresses more
accurately what the designers really do and
places a high weight on evaluation, i.e. both
users and experts should evaluate the design
development constantly.
            Methods for
        user-centered design
             continued
4. The Star Life Cycle continued
By relying on what designers really do rather
than what they should do according to the
more structured Multiview approach, one could
also say that the Star Life cycle adopts an
approach that is more experimental, more
flexible and less structured than the traditional
approaches such as Multiview or the Waterfall
model.
            Methods for
        user-centered design
             continued
4. The Star Life Cycle continued
The Star Life Cycle is often described to adopt
an alternating waves approach, which is
adding a flexible bottom-up approach to the
more traditional, well-structured top-down
approach known from Multiview and the
Waterfall model.
            Methods for
        user-centered design
             continued
4. The Star Life Cycle continued


The Star Life Cycle approach recommends
rapid prototyping, constant evaluation of the
product and step-by-step development and
refinement until the final outcome is reached.
           Methods for
       user-centered design
            continued
4. The Star Life Cycle continued
This flexibility has several advantages in the
rapidly changing field of multimedia. The
reason for this is that in the course of
developing a device, there might be necessary
changes that were initially not considered but
that need to be implemented in order to bring
this device up to date.
            Methods for
        user-centered design
             continued
4. The Star Life Cycle continued
The main stages in the star life cycle consist of
similar activities as the stages in the Waterfall
model:
Analysis, Requirements specification, Design,
Implementation.
             Methods for
         user-centered design
              continued
4. The Star Life Cycle continued
However, in the Star Life Cycle, system
development may begin at any stage (uni-
directional arrows) and may be followed by any
of the other stages (bi-directional arrows).


A figure to illustrate this can be found on the next
slide.
               The Star Life Cycle

                                      Task
  Implementation
                                     Analysis




Prototyping        Evaluation         Requiremens
                                      Specification




                    Conceptual
                   Design/Formal
                      Design
            Methods for
        user-centered design
             continued
4. The Star Life Cycle continued


The Star Life Cycle process also involves a lot
more iteration than the Waterfall and Life Cycle
Approach. The requirements, design and the
product gradually evolve and become
increasingly well defined.
           Methods for
       user-centered design
            continued
4. The Star Life Cycle continued


The Star Life Cycle makes a distinction
between
1. Conceptual Design
2. Physical Design
           Methods for
       user-centered design
            continued
4. The Star Life Cycle continued


Conceptual Design tells what is required,
i.e. what the system should do, what the users
need to know, etc.
            Methods for
        user-centered design
             continued
4. The Star Life Cycle continued
Physical Design tells how things that are
required can be achieved.
The conceptual/physical distinction contributes
to designing good systems because it leaves a
lot of room for modification while the prototype
design process has already started.
            Methods for
        user-centered design
             continued
4. The Star Life Cycle continued
Deferring decisions as to who or what will
perform which functions to a later stage of the
design process is particularly important in
highly dynamic (=rapidly changing) fields such
as IT. If there are rapid technology changes,
this will have a strong impact on the outcome
of the final design, because the changes also
determine what design the user desires.
            Methods for
        user-centered design
             continued
4. The Star Life Cycle continued
This may get clearer with the following
example:
Several years ago hardly any mobile phone
had the option to send and receive SMS (text
messages). Nowadays, it would be hard to sell
a phone without this option.
           Methods for
       user-centered design
            continued
4. The Star Life Cycle continued


User Interface design before SMS was made
possible needed to remain open for a sudden
change in user demands, because once SMS
became available, it became highly popular
and most users wanted to have this option.
            Methods for
        user-centered design
             continued
4. The Star Life Cycle continued


In more classical models such as the Waterfall
model, it would be more difficult to adjust to
these rapid changes in user demands.
The Star Life Cycle therefore tries to meet
these demands in a flexible way.
            Methods for
        user-centered design
             continued
4. The Star Life Cycle continued


In summary, the Star Life Cycle stresses on
rapid prototyping, alternating waves of analytic
and well-structured (top-down) and flexible
(bottom-up) approaches.
It also stresses on realistic and user-centred
evaluation.
            Methods for
        user-centered design
             continued
4. The Star Life Cycle continued


Because development of an interface design
can begin from any point in the star (see slide
with the figure), many limitations of traditional
models such as the Waterfall and traditional
Life Cycle Model can be overcome.
           Methods for
       user-centered design
            continued
4. The Star Life Cycle continued


Whilst the Star Life Cycle makes heavy use of
prototypes, these are not the only models in
the process of developing the interface, e.g.
sketches, scenarios or formal notations are
also applied and it very much depends on the
context where they will be most effective.

				
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posted:9/14/2011
language:English
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