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CHAPTER 20 Introduction to Systems Development and Systems Analysis -…
CHAPTER 20
Introduction to Systems Development and Systems Analysis
Reasons companies change their systems
Improved business process
Competitive advantages
Productivity gains
System integration
Technological changes
Change in user or business needs
Systems age and need to be replaced
Systems Development
System Development life cycle
a 5 step process used to design and implement a new system
1. System Analysis
the information needed to purchase, develop, or modify a system is gathered
using the limited resources, development request are screened and prioritized
to determined the feasibility of the proposed project
if feasible, info of system's users and managers are needed to be document the systems requirements used to select new system
system analysis report is prepared and submitted to the info systems steering committee
2. Conceptual Design
analyst decide how to meet user needs, identify and evaluate design alternatives and develop detailed specifications for what the system is to accomplish and how it is to be controlled
first task, identify and evaluate appropriate design alternatives (buying software, developing it in-house)
conceptual design requirements are communicated to the steering com
3. Physical Design
broad, user-oriented conceptual design requirements are translated into the detailed spec used to code and test software, design input/output, create files/database, develop procedures, implement controls
4. Implementation and Conversion
company hires and trains employees, test and modifies procedures, establishes standards and controls, completes documentation, moves to the new system and detects and correct design deficiencies
new hardware, software are installed and tested
new system were used and the old one are dismantle
system development is complete when operational system is delivered
5.Operation and Maintenance
system is periodically reviewed, necessary modifications and improvements are made
operate system
modify system
do ongoing maintenance
deliver improved system
The Players
number of people must cooperate to successfully develop and implement an AIS
management
to emphasize the importance of involving other users in the process
provide support and encouragement for development projects
align systems w corporate strategies
establishing system goals and objective
Users
AIS users communicate their information needs to system developers
project development team/steering community, manage system development
accountants- design, test, audit the controls that ensure the accurate and complete processing data
Information Systems Steering Committee
high-level management who plan and oversee the IS function
setting IS policies that govern the AIS
ensuring top-management guidance and control
coordinating and integrating systems activities
Project Development Team
a team of systems analyst and specialists, managers, accountants, users to guide its development
to ensure timely and cost-effective completion, proper consideration to human element, communicate project status to top management and the steering committee
System Analysts and Programmers
system analyst
- people who help users determine their information needs, study existing systems and design new ones, prepare specifications used by computer programmers
computer programmer
- people wo write and test programs using the specifications developed by the analyst and modify and maintain existing computer programs
External Players
customers, vendors, external auditors, governmental entities
example
- Walmart vendors are required to implement and use electronic data interchange
Planning Systems Development
Systems development plans:
Project development plan
doc showing project requirements (people, hardware, software, financial), cost benefit analysis, how a project will be completed
Master Plan
how, who, will, when it will be developed
how needed resources will be acquired
status of projects in process
prioritization of planned projects and criteria
projects w higher priorities are developed first
3 year planning horizon is common, updated quarterly or monthly
Planning Techniques
program evaluation and review technique (PERT)
a way to plan, develop, coordinate, control and schedule systems development activities; all activities and precedent and subsequent relationships among activities, are identified in PERT diagram (pg624)
critical path
- path that require greatest amount of time
if any activity on critical path is delayed, the whole project is delayed
resources can be shifted to critical path activities to reduce project completion time
Gantt Chart
a bar graph used for project planning
shows project activities on the left
top - units of time
horizontal - expected time to take of each activity
Advantage
- ability to show graphically the entire schedule including date and status progress for large project
Disadvantage
- do not show the relationship among project activities
Feasibility Study (business case)
an investigation to determine whether it is practical to develop a new application or system
prepared w input from management, accountants, system personnel, users
Aspects of feasibility study:
1. Economic
determining whether system benefits justify the time, money and resources required to omplement it
Capital Budgeting: Calculating Economic Feasibility
capital budgeting model
a return-on-investment technique used to compare estimated benefits and costs to determine whether a system is cost beneficial
payback period
a return0on-investment technique used to calculate the number of years required for the net savings of a system to equal its initial cost
choose shortest payback period
Net Present Value (NPV)
estimated future cash flows are discounted back to the present, using a discount rate that reflects time value of money
choose highest NPV
Internal rate of return (IRR)
effective interest rate that results in an NPV zero
highest IRR is selected
2. Technical
determining if a proposed system can be developed given the available technology
4. Scheduling
determining if a proposed system can be developed and implemented in the time alloted
4. Operational
determining if the organization has access to people who can design, implement and operate the proposes system and if employees will use the system
3. Legal
determining if a proposed system will comply with all applicable federal and state laws, administrative agency regulations and contractual obligations
Behavioral Aspects of Change
positive and negative ways people react to change; managing these behavioral reactions is crucial to successfully implementing a new system
why behavioral problem occur
fear
top-management support
experience w prior change
communications
disruptive nature of change
manner in which change is introduced
biases and emotions
personal characteristics and background
how people resist change
aggression
resistance to change intended to destroy, cripple or weaken system effectiveness, such as increased error rates, disruptions or deliberate sabotage
projection
resistance to change the blames anything and everything on the new system, such as it becomes the scapegoat for all real and imagined problems and errors
avoidance
resistance to change where users ignore a new IS in the hope that the new system will eventually go away
preventing behavioral problems
obtain management support
to provide resources and motivate others to assist w system development
meet user needs
involve users
participate by suggesting and helping in making decisions
participant could be more knowledgeable, better trained and more committed to using the system
provide trainings
to make the users understand the system better
reexamine performance evaluation
to ensure they are congruent to the system
1 more item...
System Analysis
request for system developments
a written request for a new or improved system that describes the current system's problems, the reasons for the change and the proposed system's objectives, benefits and costs
1. Initial Investigations
investigate each development activity to define the problem to be solved
make a preliminary assessment of feasibility
prepare a proposal to conduct systems analysis
2. System Survey
study the present system to gain a thorough understanding of how it works
3. Feasibility Study
develop a more thorough feasibility analysis, especially w respect to economic costs and benefits
4. Information Needs and Systems Requirement
identify information needs of users
determine objectives and requirement of the new system
5. System Analysis Report
provide management w the findings of the analysis phase
to summarize and document analysis activities
Strategies to determine AIS Requirement
ask users what they need
analyze external systems
examine existing systems
create prototype
interviews
questionnaires
observation
systems documentation
documentation
physical models
- how a system functions by describing document flow, computer processes performed and the people performing them, equipment used
logical models
- focus on essential activities (what is being done) and the flow of information
systems survey report
a report that summarizes all the activities that took place during the system surveys, including all relevant information