Turban, Aronson, and Liang
Decision Support Systems and Intelligent Systems,
Seventh Edition
Chapter 6
Decision Support System
Development
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-1
Systems Development Life Cycle
• Four phases
–
–
–
–
Planning
Analysis
Design
Implementation
• Cyclical
• Can return to other
phases
• Waterfall model
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-2
• Planning, analysis, design, and implementation are
the four fundamental phases. The minor phases
include: In the planning phase: (1) identify business
value, (2) analyze feasibility, (3) develop work plan,
(4) staff project, and (5) control and direct project.
• In the analysis phase: (6) analyze problem, (7)
gather information, (8) model process(es), and (9)
model data. In the design phase: (10) design
physical system, (11) design architecture, (12)
design interface, (13) database and files, and (14)
design interface(s). In the implementation phase:
(15) construction, and (16) installation
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-3
Case Tools
•
CASE (Computer-Aided Software Engineering)
tools are essentially information systems for
systems analysts. CASE tools can help manage
every aspect of developing a system. It is essentially
a DSS for an information system development team.
It is important because through it a consistent
information system can be developed, it enforces
consistency, and provides communication among
the development team.
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-4
Case Tools
• Computer-aided software design tools
– Upper CASE –
• Creates systems diagrams
– Lower CASE
• Manages diagrams and code
– Integrated CASE
• Combination
• design tools
– Enterprise class repository and collaboration
– UML modeling
• Analysis and design software
• Code debugging methods
• Testing and quality assurance tools
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-5
Successful Project Management
•
•
•
•
•
Establish a baseline
Define scope of project
Manage change and scope creep
Get support from upper management
Establish timelines, milestones, and
budgets based on realistic goals
• Involve users
• Document everything
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-6
Implementation Failures
•
•
•
•
•
•
Lack of stakeholder involvement
Incomplete requirements
Unrealistic expectations
Lack of skill or expertise
Inadequate human resources
New technologies
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-7
Evolutionary Disruptors
• Development environment
– Organizational cultural factors
– Loss of top management support
– User experience
• Development process
– User education, support, involvement,
training
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-8
Project Management Tools
• Project management software can
allow:
– Collaboration among disparate teams
– Resource and program management
– Web enabled
– analyses project data
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-9
Alternative Development
Methodologies
• Parallel development
– Multiple development on separate systems
• RAD
– Quick development allowing fast, but limited
functionality
• Phased development
– Sequential serial development
• Prototyping
– Rapid development of portions of projects for user
input and modification
– Small working model or may become functional part of
final system
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-10
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-11
• Compare a throwaway (design) prototype to a
system prototype.
•
• Throwaway prototyping is essentially the same,
except that the prototype developed is a proof of
concept system. It shows that the ideas work, and
that the ideas can then be implemented in some
viable delivery vehicle. For example, it is possible
to develop a system in Excel to test the formulas,
and later to switch to a programming language
like Visual Basic for faster run times.
•
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-12
DSS Development Methodology
•
•
•
•
Prototyping
Iterative design
Adaptive design
Incremental design
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-13
• Define prototyping.
• Prototyping involves performing the
analysis, design, and implementation
phases concurrently, and repeatedly.
It is a cyclic variation on the SDLC.
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-14
DSS Prototyping
• Short steps
–
–
–
–
Planning
Analysis
Design
Prototype
Immediate stakeholder feedback
Iterative
In development of prototype
Within the system in general
Evaluation integral part
Control mechanism
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-15
DSS Prototyping
• Advantages
– User and management
involvement
– Learning explicitly
integrated
– Prototyping bypasses
information requirement
– Short intervals between
iterations
– Low cost
– Improved user
understanding of
system
• Disadvantages
– Changing requirements
– May not have thorough
understanding of
benefits and costs
– Poorly tested
– Dependencies,
security, and safety
may be ignored
High uncertainty
Problem may get lost
Reduction in quality
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-16
• Define change management.
•
Change management is a process
for handling changes to existing
applications
or
the
computer
environment,
including
network
changes, software upgrades and
database
changes.
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-17
Change Management
•
•
•
•
Crucial to DSS
People resistant to change
Examine cause of change
Lewin-Schein change theory steps
– Unfreeze
• Create awareness of need for change
• People support what they help create
– Move
• Develop new methods and behaviors
• Create and maintain momentum
– Refreeze
• Reinforce desired changes
• Establish stable environment
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-18
DSS Technology Levels
• DSS primary tools
– Fundamental elements
• Programming languages, graphics, editors, query systems
• DSS generator (engine)
– Integrated software package for building specific DSS
• Modeling, report generation, graphics, risk analysis
• Specific DSS
– DSS application that accomplishes the work
• DSS primary tools are used to construct integrated
tools that are used to construct specific tools
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-19
DSS
• Hardware
– PCs to multiprocessor mainframes
• Software
– Involves multiple criteria
– Develop in house, outsource, or buy off the
shelf
– Off the shelf software rapidly updated; many on
market
– Prices fluctuate
– Different tools available
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-20
DSS
• Team developed DSS requires substantial
effort to build and manage
• End user developed DSS
– Decision-makers and knowledge workers
develop to solve problems or enhance
productivity
• Advantages
–
–
–
–
Short delivery time
User requirements specifications are eliminated
Reduced implementation problems
Low costs
• Risks
– Quality may be low
– May have lack of documentation
– Security risks may increase
© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition,
Turban, Aronson, and Liang
6-21