Management Information Systems By Effy Oz

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Management Information SystemsBy Effy Oz Andy
Jones
Chapter 11 System Planning and Development
www.cengage.co.uk/oz
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Objectives

• Explain the importance of and steps in IT
  planning
• Describe the systems development life cycle,
  which is the traditional approach to systems
  development
• Explain the challenges involved in systems
  development
• List the advantages and disadvantages of
  different system conversion strategies

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Objectives (continued)

• Enumerate and explain the principles of agile
  systems development methods
• Explain the concept of systems integration
• Discuss whether IS professionals should be
  certified

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Planning Information Systems

• Enterprise ISs gaining in popularity
• High risk involved in implementation
• Successful integration of system vital
• Planning of IS necessary
• Align IS and organizational strategies

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Steps in Planning Information Systems

• IS planning includes several key steps
• Create IS mission statement
• Articulate vision for IS
• Create IS plans
• Create operations plan
• Create budget

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Steps in Planning Information Systems (continued)
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Steps in Planning Information Systems (continued)

• Mission statement most important overarching
  goal of organization
• IS mission statement describes goal of IS
• Should be compatible with organizational mission
  statement
• CIO develops strategic plan for implementation
• Goals broken down into objectives
• Objectives broken down to operational details

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Steps in Planning Information Systems (continued)

• IT planning similar to planning of other
  resources
• Growing proportion of IT funds spent on software
• More purchasing
• Less developing in-house

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The Benefits of Standardization in Planning

• Major goal of planning is standardization
• Many benefits
• Cost savings
• Better bargaining power
• Applies to hardware and software
• Efficient training
• Smaller variety of software
• Efficient support
• More specialization

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From Planning to Development

• After planning decide how to obtain systems
• Usually software
• Approaches to systems development universal
• Two approaches
• Systems development life cycle (SDLC)
• Nontraditional methods
• Agile methods more efficient
• Prototyping fast development of application
  based on initial requirements

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The Systems Development Life Cycle

• Large ISs conceived with systems development life
  cycle (SDLC)
• SDLC also known as waterfall development
• Consists of sequential phases
• Organizations sometimes take shortcuts
• Four major phases
• Analysis
• Design
• Implementation
• Support

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The Systems Development Life Cycle (continued)
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Analysis

• Systems analysis five-step process
• Investigation
• Technical feasibility study
• Economic feasibility study
• Operational feasibility study
• Requirements definition

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Analysis (continued)
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Analysis (continued)

• First step is investigation
• Determine if system necessary
• Small team interviews employees
• Feasibility studies conducted after IS warranted
• Technical feasibility
• Determine if components exist
• Adequate hardware

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Analysis (continued)

• Economic feasibility study
• Cost/benefit analysis spreadsheet showing costs
• Benefits must outweigh costs
• Return on investment (ROI) most accurate
  economic analysis
• Difference between stream of benefits and costs
• Many benefits are intangible

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Analysis (continued)
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Analysis (continued)

• Operational feasibility study
• Determine how new system will be used
• Organizational culture general tone of corporate
  environment
• System compatibility with culture
• Requirements definition
• Project team installed
• System requirements functions expected from
  system

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Design

• Second step in systems development is design
• Systems design three steps
• Description
• Construction
• Testing
• If purchasing system must determine how to adapt
• Construction requires changing programming code

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Design (continued)
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Design (continued)

• Symbols used to communicate ideas
• Visual information grasped more quickly
• Data flow diagram (DFD) describes flow of data
• Four symbols
• External entities
• Processes
• Data stores
• Direction of data flow

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Design (continued)
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Design (continued)

• DFD symbols
• External entities are external individuals and
  groups
• Processes are events that change data
• Data store is resting data
• Data flow is direction that data moves
• Simplicity of DFD is advantage
• DFD suitable for describing non-computer based IS
• DFD cannot describe system completely

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Design (continued)
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Design (continued)

• Unified modeling language (UML) de facto
  standard for diagramming
• Helps developers communicate features
• Provides standard symbols and notations
• Consists of diagrams describing software
• Use case
• Class
• Interaction
• State
• Activity
• Physical components

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Design (continued)
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Design (continued)

• Construction
• Mostly programming
• Takes months to years
• Testing done on completed modules
• Walk-through logic of program
• Simulation of actual program execution
• System testing
• Test entire integrated system
• Try to outsmart system
• Poor testing causes many failures

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Implementation

• Implementation Two steps
• Conversion
• Training
• Conversion switching old system to new
• Four basic strategies
• Parallel conversion old system used with new
  system at first
• Phased conversion break IS into modules and
  integrate one at a time
• Cut-over conversion immediately replace all
• Pilot conversion introduce in one business unit
  at a time

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Implementation (continued)
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Support

• Support two responsibilities
• Maintenance
• Post-implementation debugging
• Updates
• Adding postponed features
• User help
• Longest phase of system life cycle

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Agile Methods

• Agile methods alternatives to SDLC
• Treat software development as series of contacts
  with users
• Fast development of software
• Improve software after user specifications
  received
• Iterative programming

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Agile Methods (continued)

• Popular agile methods
• Extreme programming (XP)
• Adaptive software development (ASD)
• Lean development (LD)
• Rational unified process (RUP)
• Feature driven development (FDD)
• Dynamic systems development method (DSDM)
• Scrum
• Crystal

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Agile Methods (continued)

• Agile method risks
• Analysis phase limited or eliminated
• Risk of incompatibilities
• Less documentation
• Difficult modification
• Manifesto for Agile Software Development
  prioritizes individuals and interactions over
  processes
• Light but sufficient development process

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Agile Methods (continued)
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Agile Methods (continued)

• User involvement encouraged throughout process
• Test modules immediately after completion
• Communication with users informal
• Two programmers per module

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When to Use Agile Methods

• Best to use agile method
• When system is small
• Analysis less important
• Small investment of resources
• For unstructured problems
• Users cannot specify all requirements at start
• Unfamiliar with technology
• Difficult to conceptualize

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When Not to Use Agile Methods

• Do not use agile methods when
• System is large
• System failure entails great financial loss
• Designed to interface with other systems
• SDLC recommended for complex systems
• Documentation is key

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When Not to Use Agile Methods (continued)
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Systems Integration

• Systems integration combine disparate systems
• Examines needs of entire organization
• Allows data to flow between units
• Some service companies specialize in this
• Integration more challenging than development
• Interface legacy systems with new systems

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Systems Integration (continued)
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Systems Integration (continued)

• Systems integrators must be skilled in hardware
  and software
• Difficult to overcome incompatibility issues
• Systems integration may span several
  organizations
• Integration with telecommunications

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Summary

• IT planning important because of high investment
  rate
• Standardization important part of IT planning
• Systems development life cycle (SDLC) has
  well-defined phases
• Purpose of systems analysis is to determine needs
  the system will satisfy

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Summary (continued)

• Feasibility studies determine if system is
  possible and desirable
• System requirements detail features needed
• Developers outline system components graphically
• Unified Modeling language used to create model of
  desired system
• Implementation includes training and conversion
  to new system

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Summary (continued)

• Support entails maintenance and satisfying
  changing needs
• Agile methods are popular alternative to
  traditional systems development cycle
• Systems integration more complicated than systems
  development
• Great responsibility of IS professionals results
  in certification requirements