Introduction to Information Systems Models and Methodologies - High Level Models and Methodologies for Information Systems - page 8

Table 1.1 Different types of ISDM, based on Avison and Taylor ( 1997 )
Problem
situation

Requirements Methodologies

Well de ned Clear Technical, rigid, hard approaches. Ex.: SSADM

Well de ned Unstable Technical, rigid, problem-oriented and focused on tools

rather that stages. Ex.: STRADIS

Unstructured Unstable Soft approaches, context and user-based. Ex.: SSM

N/A Unstable User-centric and focused on subjectivity. Ex.: ETHICS

Complex Unstable Contingency models, hybrid approaches. Ex.: Multiview

complete. SSADM was originally intended for use by government entities and large
projects, so it is ideal for stable requirements and is heavily reliant on documen-
tation (Schumacher 2001 ).
The second class of ISDM includes all methodologies that are applicable to well-
structured problem situations, where the ultimate goals are clear, but where user
requirements are likely to change along the process (Avison and Taylor 1997 ).
Structured analysis and design of information systems (STRADIS) is an example of
this class of ISDM. It is essentially a traditional methodology; however, it focuses
heavily on the tools necessary to solve speci

c problems, instead of attempting to
outline a generic set of stages that should be followed for all situations, therefore
making it a much more problem-oriented solution (Britts 2011 ).
The third class of ISDM is comprised of methodologies which are applicable to
unstructured problem situations, where objectives and requirements are unclear and
most likely unstable (Avison and Taylor 1997 ). Such situations call for an approach
that focuses on the wider context of the project, and the subjective views of the
users and developers, thus these methodologies are commonly known as

“ soft ”

approaches (as opposed to approaches that emphasize the technical pro-

cesses and tools). The prime example is the soft systems methodology (SSM) which
was precisely intended to bridge the gap between the different (and often con-

“ hard ”

flicting) views of the stakeholders involved in the development project. To achieve
this, SSM relies on the building of conceptual models that synthesize the problem
situation, facilitating its simpli

a 2008 ).
The fourth class of ISDM consists of methodologies that are applicable to sit-
uations where user interaction is very high and/or where user acceptance is a major
factor, such as in highly commercial projects. An example is the effective technical
and human implementation and computer-based systems, or ETHICS methodology,
an approach which is heavily focused on user participation and the impact of the
system on the working environment of the users (Avison and Taylor 1997 ).
The

cation (S á nchez and Mej í

final class of ISDM comprises situations where the problem sit-
uation is too complex, requiring contingency solutions to the system development
(Avison and Taylor 1997 ). Such situations are usually met by resorting to hybrid
methodologies that pick aspects from various others, in order to reach a solution
that is appropriate for the particular situation at hand. The Multiview methodology
is an example of this hybrid approach.

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