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Study Guide
Systems Analysis the process of understanding and specifying in detail what the information system should do
Systems Design the process of specifying in detail how the many components of the information system should be physically implemented
Systems analyst a business professional who uses analysis and design techniques to solve business problems using information technology
Analyst approach to problem solving research and understand the problem Verify that the benefits of solving the problem outweigh the costs Define the requirements for solving the problem Develop a set of possible solutions (alternatives) Decide which solution is best, and make a recommendation Define the details of the chosen solution Implement the solution Monitor to make sure that you obtain the desired results
System a collection of interrelated components that function together to achieve some outcome
Information system a collection of interrelated components that collect, process, store, and provide as output the information needed to complete business tasks
Subsystem a system that is part of a larger system
Supersystem a larger system that contains other systems
Functional decomposition dividing systems into components based on subsystems that in turn are further divided into subsystems
Parts of a system inputs, hardware, people, software, data, procedures, outputs
System boundary the separation between a system and its environment that inputs and outputs must cross
Automation boundary the separation between the automated part of a system and the manual part of a system
Study Guide
Transaction processing systems information systems that capture and record information about the transactions that affect the organization
Management information systems information systems that take information captured by transaction processing systems and produce reports that management needs for planning and control
Executive information systems information systems for executives to use for monitoring the competitive environment and for strategic planning
Decision support systems support systems that allow a user to explore the impact of available options or decisions
Communication support systems support systems that allow employees to communicate with each other and with customers and suppliers
Office Support systems support systems that help create and share documents, including reports, proposals, and memos
Tools software products used to help develop analysis and design specifications and completed system components
Techniques strategies for completing specific system development activities
Analysts need to know what the organization does What makes it successful? What its strategies and plans are What its traditions and values are
People knowledge how people: Think Learn React to change Communicate Work (in a variety of jobs and levels)
Business process reengineering a technique that seeks to alter the nature of the work done in a business function with the objective of radically improving performance
Study Guide
Analysis phase one phase of the SDLC whose objective is to understand the user needs and develop requirements
Problem domain the area of the user’s business for which a system is being developed
Defining the systems requirements review, analyze, and structure information obtained so that analysts can develop an understanding of requirements (drawing diagrams) – model processes
Design phase the phase of the SDLC where the system and programs are designed
Application the portion of the new information system that satisfies the user’s needs in the problem domain (provides processing functions for the business requirements)
Implementation phase the phase of the SDLC where the new system is programmed and installed
Support phase the phase of the SDLC that occurs after the system is installed (maintain the system, enhance the system, support the users
Help desk the availability of support staff to help the users with any technical or processing problem associated with an information system
Waterfall method a method of executing an SDLC where one phase leads (falls) to the next phase
Overlapping activities during the life cycle that overlap (efficiency) analyzing needs while designing forms or reports
Project management organizing and directing of other people to achieve a planned result within a predetermined schedule and budget
Client the person or group who funds the project
Study Guide
Oversight committee clients and key managers who review and direct the project, such as a board of trustees for a company
User the person or group who will use the new system
Weighted scoring a method to prioritize projects based on criteria with unequal weighs
Reasons project initiated respond to opportunity; resolve a problem; conform to directive
Business benefits the benefits that accrue to the organization; often measured in monetary terms
System scope document a very preliminary prototype built to illustrate that a solution to a business need is feasible
Proof of concept prototype a document-containing description, business benefits, and system capabilities- to help define the scope of a new system
Context document a graphical diagram showing the scope of a system
Work breakdown structure the hierarchy of tasks, activities and phases of a project; one method to estimate and schedule the task of a project
Task/activity/phase task- smallest piece of work that is identified and scheduled; activity – a group of related tasks; phase- Is made up of a group of related activities
Pert/cpm a method of scheduling a project based on individual task or activities
Critical path the path on a PERT chart that indicates the shortest completion period for the project
Gantt chart a bar chart that represents the tasks and activities of the project schedule
Study Guide
Models of system components flowchart Data flow diagram (DFD) Entity-relationship diagram (ERD) Structure chart Use Case diagram Class diagram Sequence diagram
Tool software support that helps create models or other components required in the project
Case tool a computer aided system engineering tool designed to help a system analyst complete development tasks
Technique a collection of guidelines that help an analyst complete a system development activity or task
Techniques used in sys development strategic planning; project management; user interviewing; data-modeling; relational database; structured analysis design; structured analysis technique; structured programming; software- testing; object-oriented analysis and design
Structured approach system development using structured analysis, structured design, and structured programming techniques
Structured program a program or program module that has one beginning and one ending, and for which each step in the program execution consists of sequence, decision, or repetition constructs
Top down programming dividing more complex programs into a hierarchy of program modules
Structured design a technique providing guidelines for deciding what the set of programs should be, what each program should accomplish, and how the programs should be organized into a hierarchy
Study Guide
Structure chart a graphical model showing the hierarchy of program modules produced by the structured design technique
Structured analysis a technique that helps the developer define what the system needs to do (the processing requirements), what data the system needs to store and use (data requirements), what inputs and outputs are needed, and how the functions work together overall to accomplish tasks
Data flow diagram a graphical model showing the inputs, processes, storage, and outputs of a system produced in structured analysis
Entity-relationship diagram a graphical model of the data needed by a system, including things about which information is stored and the relationships among them, produced in structured analysis and information engineering
Information engineering a traditional system development methodology that focuses on strategic planning, data modeling, and automated tools, thought to be more rigorous and complete than the structured approach
Incremental development a development approach that completes parts of a system in one or more iterations and puts them into operations for users
Automated tools improve speed and quality of system development work no matter which methodology is being used
Case tool contains a database of information about the project, called a repository
Repository a database that stores information about the system in a CASE tool, including models, descriptions, and references that link the various models together
Logical model any model that shows what the system is required to do without committing to any one technology
Analysis Phase activities gather information; define system requirements; prioritize requirements; prototype for feasibility
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Group support system a computer system that enables multiple people to participate with comments at the same time, each on the user’s own computer
Structured walkthrough a review of the findings from your investigation and of the models built based on those findings
Sys requirements, what you need What are the business processes and operations? How are the business processes performed? What are the information requirements?
Gathering Information 7 fact finding techniques: Review existing reports, forms, and procedure descriptions Conduct interviews and discussions with users Observe and document business processes Build prototypes Distribute and collect questionnaires Conduct JAD sessions Research vendor solutions
Purpose of Prototype to have a working model that will test a concept or verify and approach
Data flow diagram a diagram that represents system requirements as processes, external agents, data flows, and data stores
External agent a person or organization, outside the system boundary, that supplies data inputs or accepts data outputs
Process a symbol on a DFD that represents an algorithm or procedure by which data inputs are transformed into data outputs
Data flow an arrow on a DFD that represents data movement among processes, data stores, and external agents
Data store a place where data are held pending future access by one or more processes
Study Guide
Levels of abstraction any modeling technique that breaks the system into a hierarchical set of increasingly more detailed models
Context diagram a DFD that summarizes all processing activity within the system in a single process symbol
DFD fragment a DFD that represents the system response to one event within a single process symbol
Event-partitioned model, diagram O a DFD that models system requirements using a single process for each event in a system or subsystem
Information overload difficulty in understanding that occurs when a reader receives too much information at one time
Rule of 7 & 2 the rule of model design that limits the number of model components or connections among components to no more than nine
Minimization of interfaces a principle of model design that seeks simplicity by limiting the number of connections among model components
Balancing equivalence of data content between data flows entering and leaving a process and data flows entering and leaving a process decomposition DFD
3 common consistency errors differences in data flow content between a process and its process decomposition; data outflows without corresponding data inflows; data inflows without corresponding outflows
Process decomposition shows the internal details of a higher-level process in a more detailed form
Black hole a process or data store with a data input that is never used to produce a data output
Miracle a process or data store with a data element that is created out of nothing
