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A GENERAL EVALUATION MODEL CRITERIA FOR 
SELECTING AN OPTIMUM STRUCTURED DEVELOP- 
MENT METHODOLOGY 
Alot of Structured Development Methodologies exist in the 
Information Science/ Technology scene. Some look similar 
in many respects, some use techniques that overlap in 
concepts, the advantages or otherwise of some are more 
apparent in some types of Systems than the others, and 
some lay more emphasis on some aspects of Information 
Systems development. This state of affairs leaves the 
Systems Analyst and Designer in a quandary over which of 
these methodologies could suit a particular Systems 
Development project. The reported Research focuses on 
the determination of a general evaluation model criteria for 
selecting an optimum Structured Development Methodology 
for the development of a wide range of Information 
Systems. 
Framework for Evaluation: 
This framework (see Figure 3) can be conceptualised as a 
scenario in which the problem domain or Object System 
(the Organisation, considered as a problem area) is to be 
assessed against a background of many recommended 
approaches (or methodologies) for the development of 
information systems. 
  
EVALUATION 
RULES 
  
  
  
  
* How decisions can be taken on very closely scored 
methodologies (could be through increasing the levels 
of details evaluated) 
The Different Methodologies would be introduced into the 
evaluation framework 
(matrices or tables) determined in the evaluation model. 
The Evaluation Model would simply be a model of selection 
processes, resulting in a priority list of methodologies,and 
also in a final decision. This model is the core of the 
scenario and is blown further as shown in Figure 4. 
Further Explanation of the Framework 
€ STEP O: This involves outlining of the principal phases 
through which the development process for the Object 
System would (or should) have to go through. In the 
presented example of Topographic Database Systems, the 
phases of development are [Radwan, undated] Design, 
Implementation and Operation. 
€ STEP 1: Here the functions and/or activities within the 
phases defined above are listed. 
  
  
  
  
    
  
DIFFERENT 
METHODOLOGIES 
AND 
TECHNIQUES 
  
  
  
PRIORITY LIST 
OF | > FINAL 
METHODOLOGIES DECISION 
AND TECHNIQUES 
  
Figure 3 An Overview of the Evaluation Process 
The Evaluation Rules should include the following 
guidelines (based on the nature of the problem area for the 
Object System): 
* The composition of an evaluation committee 
* Aspects (perspectives) of methodologies to be 
evaluated 
* Level of decomposition (as provided for by the 
methodology) to be considered or seen as desirable. 
* The level of details to be evaluated per methodology 
* Howthe extent of subjectivity in evaluation (particularly 
Weighting) can be reduced (could be through iterations 
using the Delphi Technique of quantitative studies) 
€ STEP 2: The importance of each phase and function/ 
activity is weighted. This is done independent of any 
considerations for any methodology. It would have more to 
do with the peculiar circumstances of our Object System, 
and each evaluator would state reasons why a particular 
phase, function/activity is given more importance relative to 
the rest. Viewed as an individual judgement, weighting can 
be highly subjective because the phases are not mutually 
exclusive and the evaluators have different perceptions and 
experiences. Through iterations, the evaluators can re- 
evaluate their weights (where discrepancies are 
unacceptable) and move towards an acceptable mean 
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