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IS2210: Systems Analysis and Systems Design and Change
Email: [email protected]: @InstCathalDoyleWebsite: www.cathaldoyle.com
The WebsiteO I will try put notes on the website at
least a day before class
O This does not mean you can’t attend!!!
O I also have made the site very interactive
TutorialsO Location: O’Rahilly Building (ORB)
B.05
O Start Date: Thursday 10/10/2013 (bi-weekly)
O Time: 5-6pm
AttendanceO Students must attend 80% of
lectures and 80% of tutorials
O Attendance sheet will be kept at both
ObjectivesO From todays lesson you should…
O Understand what constitutes an information system
O Know the major roles of Information Systems (IS)
O Understand Analysis and Design
IS2200 TerminologyO SAD:
O IS:
O SDLC:
Systems Analysis and Design
Information Systems
Software Development Life-Cycle
O Systems Analyst:
IS professionals who specialise in analysing and designing information systems
Towards an Information Systems Definition
O We must first understand what information is
O Then we need to understand what a system is
O This will give us a better understanding of what an IS is
Data versus Information
O Data:
O Information:
Raw Facts
Data that has been processed, and useful to human beings
Example
The Information Revolution
O Information has become an important commodity such as land, labour, and capital resources
O Organisations use it to increase productivity, deliver products and services, and to make decisions
What is a System?O A collection of interrelated parts
that work together to achieve one or more common purposes.
INPUT OUTPUTPROCESS
FEEDBACK
System ComponentsO INPUT
O Captures or collects raw data from both internal and external sources
O PROCESSO Converts the raw data into a meaningful
form
O OUTPUTO Transfers the processed information to
people who will use it
O FEEDBACKO Output returned to the appropriate
members of the organisation to aid them in the evaluation or correction of the input stage
O CONTROLO Monitoring and evaluating feedback to
determine whether a system is moving toward achievement of its goal, and make necessary adjustments
What is an Information System?
O An information system is a set of interrelated components that collect, retrieve, process, store, and distribute information to support decision making and control in an organisation
Information Systems Components
O DataO HardwareO SoftwareO
Telecommunications Networks
O People
IS versus ITO Information Systems and Information
Technology are parts of a broader computer science
O Information Systems focuses on the system making use of technology, Information Technology focuses on technology and how it can help in disseminating information
O Information Technology can be considered as a subset of Information Systems
Information Systems Are NOT Just Computers!!!
O Using information systems effectively requires an understanding of the organisation, management, and information technology shaping the system
Who Uses an IS and why?
Major Roles of an IS
Support of Business Processes and Operations
Support Business
Decision Making
Support Competitive
Advantage & Decision making
OperationalLevel
TacticalLevel
StrategicLevel
O Support Business OperationsO e.g. retail information system to record
customer purchases, track inventory, pay employees
O Support Managerial Decision MakingO e.g. in store managers use system to decide
what lines to add or discontinue
O Support Strategic AdvantageO e.g. head office uses system to look at sales
trends across stores to identify ways to gain competitive advantage over other retailers
Who Develops Information Systems?
O In-House Applications
O Software Packages
O Internet-Based Application Services (Web Services)
O Outsourcing
Systems AnalysisO Understanding and specifying in
detail what an information system should do.O A detailed study of how the current
system functionsO An assessment of what users would
like to see in a new systems.
O To carry out system analysisO Requirements determinations –
interviews, JAD (Joint Application Design/Development), documentation
O Requirements Structuring - DFDs
Systems DesignO Design is another crucial phase in
the development of a system. O Specifying in detail how the parts of an
information system should be implemented
O Develop both logical design and physical design Logical design – business aspects – what is to
be done, processes to be performed Physical design – technical aspects –
concerned with h/w and s/w requirements, database tables, index structures etc…
Why Systems Analysis and Design Necessary?
O More than 50% of IS projects fail!!!
O Other Interesting Information: O 30% cancelled before completionO Systems are often not used when
completedO Systems fail to provide the expected
benefitsO 51% of projects exceed budgets by
189%, and only deliver 74% functionality
Why Such Failures?O Many fail because systems
analysts try to build wonderful systems without understanding the organisation
O Our primary goal should be to create value for the organisation
Sample IS FailuresCompany Year Outcome
Hudson Bay (Canada)
2005 Inventory system problems lead to $33.3 million loss.
UK Inland Revenue
2004/5 $3.45 billion tax-credit overpayment caused by software errors.
Avis Europe PLC (UK)
2004 Enterprise resource planning (ERP) system cancelled after $54.5 million spent.
Ford Motor Co. 2004 Purchasing system abandoned after deployment costing approximately $400 M
Hewlett-Packard Co.
2004 ERP system problems contribute to $160 million loss.
AT&T Wireless 2004 Customer relations management system upgrade problems lead to $100M loss
Defining SADO 1: A method used by companies to
create and maintain systems that perform business functions
O 2: Systems Analysis and Design as performed by the systems analysis seeks to systematically analyse data input or data flow, processing or transforming data, data storage, information output within the context of a particular organisation
QuestionsO What is the difference between data
and information?
O What are the five components of an information systems?
O What is the difference between analysis and design?
ThanksO Any Questions?
