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Building and Implementing Decision Support Systems. Week 6. DSS Examples. Bank Rate Monitor Car Point. Development Process Review. SDLC Advantages: standardized steps, formal documentation, no important area overlooked Disadvantages: too rigid, poor user-developer communication - PowerPoint PPT Presentation
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Building and Building and Implementing Decision Implementing Decision
Support SystemsSupport Systems
Week 6Week 6
2
DSS Examples Bank Rate Monitor Car Point
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Development Process Review SDLC
Advantages: standardized steps, formal documentation, no important area overlooked
Disadvantages: too rigid, poor user-developer communication
Prototyping Advantages: improved user-developer
communication Disadvantages: can extend development, user
misperceptions End-User Development
Advantages: user control, time & cost savings Disadvantages: distraction, not training in systems
development, “playing graphic designer”
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The DSS Analysis and Design Process
Functional category analysis – the developer identifies the specific functions necessary for a specific DSS from a broad list of available functions.
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Functional Categories Selection – locating knowledge within
the knowledge base for use as input Aggregation – creation or derivation
of summary statistics, such as averages or totals
Estimation – creation of model parameter estimates
Simulation – creation of knowledge about expected outcomes or consequences of specific actions
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Functional Categories Equalization – creation of
knowledge regarding conditions necessary to maintain consistency
Optimization – discovering what set of parameter values best meet a set of performance measures
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Strategies for DSS Analysis and Design
There are two common strategies for DSS development:
Programming a customized DSS: either a general purpose language like C++ or a fourth-generation language like Delphi or Visual C# can be used. This allows for development of special interfaces between the DSS and other applications.
Employing a DSS generator: these range from spreadsheets such as Excel—perhaps with some add-ins—or a more sophisticated generator such as MicroStrategy’s DSS Architect.
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Generalized DSS Development Process
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DSS Development ProcessFor unstructured problems, we employ an
alternate development strategy. There are seven basic activities in this process (not all may be performed in every project).
1. Problem diagnosis – formal identification of the problem context
2. Identification of objectives and resources – specific objectives must be described and available resources identified
3. System analysis – three categories of requirements (functional, interface, and coordination) are established.
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DSS Development Process
The remaining steps are:4. System design – the determination of
components, structure, and platform5. System construction – an iterative
prototyping approach, with small but constant refinement employed
6. System implementation – where testing, evaluation, and deployment occurs
7. Incremental adaptation – this final stage is a continual refinement of the activities of the earlier six stages.
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Tools for DSS DevelopmentThere are a variety of tools available,
roughly falling into three categories:
1. Primary development tools – these include programming languages and database query mechanisms.
2. DSS generators – at a higher level of technology, these possess integrated, diverse functionality, including decision modeling, sophisticated reporting, and database management.
3. Specific DSS applications – for some problem types there may be a commercially available package that can be acquired and customized.
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DSS Development Tool Classification
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Development Tool Selection Criteria
These criteria are particularly important in selection of a DSS generator :
1. Data management functions2. Model management functions3. User interface capabilities4. Compatibility and degree of connectivity5. Available hardware platforms6. Cost7. Quality and availability of vendor support
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DSS User Interface IssuesThe unique characteristics of a DSS
user interface stem from the unique characteristics of typical end users: They play an organizational role based on
something other than computing skills. They have latitude in exercising judgment. Their decisions have impact. They spend more time on tasks that do not
need a computer than do. The unique nature of the decisions they
make means their personal preferences must be accommodated.
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Factors Related to the Quality of the User Interface
Learning curve – how fast does the user learn?
Operational recall – how long does it take the user to recall how to use the DSS?
Task-related time – how long is the typical task?
System versatility – does it support a variety of end user tasks?
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Factors Related to the Quality of the User Interface Error-trapping and support – what type of
errors will users make? Degree of system adaptability – will it
adjust to individual use? Management of cognitive overload – to
what extent does the DSS reduce the need to remember things while using it?
Degree of personal engagement – to what extent is the DSS enjoyable to use?
Degree of guidance and structure – to what extent does the interface guide the user?
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Implementation Stage “The process of assuring that the
information system is operational and then allowing the users to take over its operation for use and evaluation” (Kendell and Kendell, 1988)
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Implementation Stage Activities Obtaining and installing the DSS
hardware Installing the DSS and making it run
on its intended hardware Providing user access to the system Creating and updating the database Training the users on the new system
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Implementation Stage Activities Documenting the system Making arrangements to support
the DSS Transfer from developers to
operations Changing previous methods Evaluating the operation and use
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Direct conversion Four basic conversion strategies
Direct conversion Parallel conversion Pilot conversion Phased conversion
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Direct conversion Stop old system, start new system Need to keep the old system in
place
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Parallel conversion Run both old system and new
system and compare the results Pointless for data-oriented DSS Acceptable for suggestion DSS
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Pilot conversion Introduce the system to a small
part of the organization Not feasible for group DSS
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Phased conversion Introduce the system in stages Good for DSS that can be divided
into several modules (GDSS) Start with most important modules
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System Conversion ViabilityTPS DSS
Direct conversion Usually unacceptable risk
Usually acceptable risk
Parallel conversion
Usually impractical
Usually practical
Pilot conversion Generally first choice
May raise operational issues
Phased conversion
Requires large effort to interface 2 DBs
Good choice for usually read only systems
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Resistance to Change “There is nothing more difficult to
take in hand, more perilous to conduct, or more uncertain in its success, than to take the lead in the introduction of a new order of things.” (Machiavelli, 1532)
Few will gain Many will lose
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Resistance to Change “The design and implementation of
a DSS is an example of planned technological change. The success or failure of a proposed DSS depends on how well this change process is managed.” (Chervany & Palvia, 1990)
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Managing Change Deals with people, not technology Organizational culture Lewin-Schein Theory of Change
Unfreezing Moving Refreezing
Mostly applies to institutional DSS
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Unfreezing Create a strong motivation for change Create a vision Based on justification of the system Clearly define the benefits 3 ways to unfreeze
1. Increase the forces that motivate change2. Reduce forces that motivate resistance3. Adjust the existing force
Should start when the project starts
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Moving Most visible component Training
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Refreezing Internal commitment to use the
systems on an ongoing basis Particularly important in DSS
3 factors that have positive effects1. Strong project champion2. Sufficient time for each change stage3. Make sure each stage a success
before continuing
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DSS Implementation Issues Technical User-related
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Technical Implementation Issues Unfamiliarity with this type of
system Response time Reliability and Availability Poor data quality
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User-related Implementation Issues User and Management Support Unstable user community Response time Training Availability of support Voluntary or Mandatory Use
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User-related Implementation Issues Change in job content Loss of status Change in interpersonal relationships Loss of power Change in decision-making approach Uncertainty or unfamiliarity or
misinformation Job security
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Ethical Issues in DSS Implementation Storage of Information Use of Information Sharing of Information Human Judgment Combining Information Error Detection and Correction
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Measuring Implementation Success 1. Ratio of actual project execution time to the
estimated time
2. Ratio of actual project development cost to budgeted cost
3. Managerial attitudes toward the system
4. How well managers' information needs are satisfied
5. Impact of the project on the computer operations of the firm
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Other MSS Success Measures System Use
User satisfaction
Favorable attitudes
Degree to which system accomplishes its original objectives
Payoff to the organization
Benefit-to-cost ratios
Degree of institutionalization of DSS in the organization
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Contributing Factors to DSS Success User involvement
User training
Top management support
Information source
Level of managerial activity being supported
Characteristics of the tasks involved (structure, uncertainty, difficulty, interdependence)
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MSS Implementation Failures Usually a closely held secret in many
organizations
Expected synergy of human and machine not developed
Managers unwilling to use computers to solve
problems
Not much formal data on MSS failures
Many informal reports on unsuccessful implementation