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Chapter 2. State of the Art of Application Development Processes
collection, (2) Design, (3) Implementation, (4) Evaluation, and (5) Deployment.
Reccurring key elements of each stage are: (1) A task analysis of the activities
done by users in their environment, (2) A ‘conceptual model’ which users see and
understand, (3) A ‘use model’ describing how the system is to be used, (4) Design
and implementation of a prototype, (5) Formal and informal testing of the system,
and (6) Evaluation of the reactions of the users. This methodology gives more formal
and detailed instructions to the developer about how to proceed during a project.
The user focus is strong but again limited to the user’s articulations.
Dick and Carey’s Systematic Design. This approach
[
Dick and Carey 1985
]
originally focused on instructional products, but can also be applied to other types
of products. The methodology is very systematic, it comprises nine steps: (1)
Identify instructional goal(s), (2) Conduct instructional analysis, (3) Identify en-
try behaviors and characteristics, (4) Write performance objectives, (5) Develop
criterion-referenced test items, (6) Develop instructional strategy, (7) Develop and
select instructional materials, (8) Design and conduct formative evaluation, and (9)
Design and conduct summarized evaluation. Before each stage, the previous is re-
visited and revised, and all stages are to be followed in order. Some stages focus
on the user but not as extensive as the previous methodologies. Due to its formal
character the guidance for the developer by this methodology is very strict.
Rapid Prototyping Methodology. The basis of rapid prototyping
[
Tripp and
Bichelmeyer 1989
]
are five stages that are not conducted in a linear manner, but
rather simultaneously. Design, development, and testing are scheduled based on
problems identified during user tests of the software. The process elapses when
errors only on a minimal level are found by the user. The process is very iterative
and has a strong focus on the user throughout all stages. The stages are in particular
(1) Assess needs and analyze content, (2) Set objectives, (3) Construct prototype,
(4) Utilize prototype, and (5) Install and maintain system. The reported advantages
by the authors of this methodology themselves are: (1) Active user participation, (2)
User requirements are immediately implemented, (3) Early detection of errors, and
(4) An accelerated development cycle. In contrast to the previous methodologies
rapid prototyping explicitly fosters the cooperation with the user. Hereby, the user
has the main influence of the development, since the subsequent steps are scheduled
based on his findings during test phases. As such, the guidance of the developer is
rather informal. Several cycles are performed in order to meet the user’s expectations
as good as possible and realize them in a final piece of software. Simultaneously, this
‘stickiness’ to the user does not allow for developments that are beyond the current
horizon of the user, since stimulation of the user does not happen.
Lifecycle for Interactive Systems Development Methodology (ISDM).
This methodology
[
Shneiderman 1997
]
has a strong focus on the user and usability.
It is very formal, elaborate, and detailed. It comprises eight stages: (1) Collect
information, (2) Define requirements, (3) Design syntax and support facilities, (4)
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