Mid term

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DFD Completeness

DFD must include all components necessary for system. Each component must be fully described in the project dictionary or CASE repository.

Ways of Assessing Project Feasibility

Economic Technical Operational Scheduling Legal and contractual Political

Written work procedure

For an individual or work group Describes how a particular job or task is performed Includes data and information used and created in the process

Name the 6 Sources of Software

Information technology services firm Packaged software producers Enterprise solutions software Enterprise Resource Planning (ERP) Cloud computing Open source software In-house developers

4 methods for determining requirements

Interviewing individuals Interviewing groups Observing workers Studying business documents

System prototypes

Iterative development process Rudimentary working version of system is built Refine understanding of system requirements in concrete terms

Interviewing Groups Disadvantage

More difficult to schedule than individual interviews

Interviewing Groups Advantages

More effective use of time Can hear agreements and disagreements at once Opportunity for synergies

Report

Primary output of current system Enables you to work backwards from the report to the data needed to generate it

Data Flow Diagramming Mechanics characteristics

Represent both physical and logical information systems Only four symbols are used Useful for depicting purely logical information flows

DFD Timing

Time is not represented well on DFDs. Best to draw DFDs as if the system has never started and will never stop

Business form

Used for all types of business functions Explicitly indicates what data flow in and out of a system and data necessary for the system to function Gives crucial information about the nature of the organization

CASE tools

Used to analyze existing systems Help discover requirements to meet changing business conditions

Information Sources For RFP

Vendor's proposal Running software through a series of tests Feedback from other users of the vendor's product Independent software testing services Customer surveys Articles in trade publications are sometimes biased (seeded by manufacturer)

Direct Observation

Watching users do their jobs Used to obtain more firsthand and objective measures of employee interaction with information systems Can cause people to change their normal operating behavior Time-consuming and limited time to observe

an Activity

a behavior that an object carries out while in a particular state represented by a sold circle with arrow attached to the bottom

Data store

data at rest (inside the system)

What are the 2 DFD guidelines

1. The inputs to a process are different from the outputs of that process 2. Objects on a DFD have unique names

1980s

4GL, CASE tools, objectoriented methods

4 Approaches to reuse

Ad-hoc Facilitated Managed Designed

3 Different Approaches to Improving Development

CASE Tools Agile Methodologies eXtreme Programming

Drawbacks to individual interviews

Contradictions and inconsistencies Follow-up discussions are time consuming may reveal new questions that require additional interviews

3 Principles of Agile Methodologies

Adaptive rather than predictive Emphasize people rather than roles Self-adaptive processes

The heart of systems development

Analysis, design and implementation

DFD Iterative Development

Analyst should expect to redraw diagram several times before reaching the closest approximation to the system being modeled.

________ is designed to support organizational functions or processes.

Application software

"What of the following is NOT a consequence of employees knowing they are being observed in their work?"

Employees may miss work.

Operational feasibility deals with project duration.

FALSE

Which of the following is NOT a factor in determining legal and contractual feasibility?

Financial budgets

Object-Oriented Analysis and Design

Based on objects rather than data or processes

"The overall process by which current methods are replaced with new methods is referred to as ________."

Business process re-engineering

Open Source Software

Freely available including source code Developed by a community of interested people Performs the same functions as commercial software Examples: Linux, MySQL, Firefox

Information Technology Services Firms

Help companies develop custom information systems for internal use

In-House Development

If sufficient system development expertise with the chosen platform exists in-house, then some or all of the system can be developed by the organization's own staff

"Which of the following is an organization that hosts and runs computer applications for other companies, typically on a per use or license basis?"

Cloud computing application provider

Which of the following are delivered after the completion of the implementation phase?

Code, documentation, training procedures, and support capabilities

3 Advantages of eXtreme Programming

Communication between developers High level of productivity High-quality code

Information Systems Analysis and Design

Complex organizational process Used to develop and maintain computer-based information systems

A case model

Consists of actors and use cases

"A ________ can be best understood as data in motion, moving from one place in a system to another."

Data flow

________ are NOT a component of data flow diagram symbols.

Data programs

Elements of Project Planning

Describe project scope, alternatives, feasibility

Written Use Cases contain

Detailed, Step-by-step description of what must occur in a successful use case

Computer-Aided Software Engineering (CASE) Tools

Diagramming tools enable graphical representation. Prototype look and feel of system

Which of the following is NOT a useful document in the analysis process?

E-mails

Which feasibility category deals with identifying financial benefits associated with the project?

Economic

New Logical

Includes additional functions Obsolete functions are removed. Inefficient data flows are reorganized.

3 Contemporary Methods for Determining System Requirements

Joint Application Design (JAD) CASE tools System prototypes

Business Case

Justification for an information system Presented in terms of the tangible and intangible economic benefits and costs The technical and organizational feasibility of the proposed system

Throwaway prototyping

Prototype is just a mockup and just a model, discarded after use

Evolutionary prototyping

Prototype needs to be built and becomes the basis of the operational system

Which tool enables you to quickly take basic requirements and create a limited working system?

Prototyping

Packaged Software Producers

Provide software ranging from broad-based packages (i.e. general ledger) to niche packages (i.e. day care management) Pre-packaged, off-the-shelf software

All of the following are documents that are helpful in understanding future systems, except ________.

Reports from future organizational studies

New Physical

Represents the physical implementation of the new system

The following is NOT an example of a type of feasibility study.

Resource feasibility

Document Analysis

Review of existing business documents Can give a historical and "formal" view of system requirements

eXtreme Programming

Short, incremental development cycles Automated tests Two-person programming teams

Activity Diagrams

Show the conditional logic for the sequence of system activities needed to accomplish a business process. Clearly show parallel and alternative behaviors. Can be used to show the logic of a use case

Drawbacks of Prototyping during requirements determination

Tendency to avoid formal documentation Difficult to adapt to more general user audience Sharing data with other systems is often not considered Systems Development Life Cycle (SDLC) checks are often bypassed

Reuse

The use of previously written software resources, especially objects and components, in new applications.

Systems Development Life Cycle (SDLC)

Traditional methodology used to develop, maintain, and replace information systems

"A use-case consists of a set of possible sequences of interactions between a system and ________ in a particular environment, possible sequences that are related to a particular goal."

User

Which of the following is a drawback of the traditional waterfall SDLC approach?

Users are locked into requirements.

Present Day

Web application development, wireless PDAs and smart phones, component-based applications, peruse cloud-based application services.

Rules for Stopping DFD Decomposition

When each process has been reduced to a single decision, calculation or database operation When each data store represents data about a single entity When the system user does not care to see any more detail

"CASE helps programmers and analysts do their jobs more efficiently and more effectively by automating routine tasks."

When they contain organizational data

a Branch

a diamond symbol containing a condition whose results provide transitions to different paths of activities represented by a diamond with 2 arrows pointing out

Object class

a logical grouping of objects sharing the same attributes and behaviors

Use case diagram

a picture showing system behavior along with the key actors that interact with the system

Economic feasibility or cost-benefit analysis

a process of identifying the financial benefits and costs associated with a development project

Object

a structure encapsulating attributes and behaviors of a real-world entity

a Merge

a symbol where different branches converge represented by a diamond with 2 arrows pointing in

Project initiation focuses on

activities designed to assist in organizing a team to conduct project planning

Prototyping

an iterative process of systems development in which requirements are converted to a working system that is continually revised through close collaboration between an analyst and users.

Planning

an organization's total information system needs are identified, analyzed, prioritized, and arranged

Intangible benefits a

benefits derived from the creation of an information system that cannot be easily measured in dollars or with certainty. Ex: improved morale

Joint Application Design (JAD)

collect system requirements simultaneously from key people Brings together key users, managers, and systems analysts

Swim lanes

columns representing different organizational units or functions of the system

Tangible cost

cost associated with an information system that can be measured in dollars and with certainty ex: Hardware costs Labor costs, or Operational costs, including employee training and building renovations.

Intangible cost

cost associated with an information system that cannot be easily measured in terms of dollars or with certainty ex: Loss of customer goodwill, Employee morale, or Operational inefficiency.

One-time cost:

cost associated with project start-up and development or system start-up ex: user training site preparation system development

Recurring cost

cost resulting from the ongoing evolution and use of a system Application software maintenance Incremental data storage expenses Incremental communications New software and hardware leases, and Supplies and other expenses (i.e., paper, forms, data center personnel)

Present value

current value of a future cash flow

1950s

efficient automation of existing processes

Logical design

features of the system chosen for development in analysis are described independently of any computer platform

Inheritance

hierarchical arrangement of classes enable subclasses to inherit properties of superclasses

Implementation

information system is coded, tested, installed and supported in the organization

Maintenance

information system is systematically repaired and improved

Enterprise Resource Planning (ERP)

integrate individual traditional business functions into modules enabling a single seamless transaction to cut across functional boundaries.

interview guide

is a document for developing, planning and conducting an interview.

Primitive DFD

is the lowest level of a DFD.

Physical design

logical specifications of the system from logical design are transformed into the technology-specific details from which all programming and system construction can be accomplished

Time value of money (TVM)

money available today is worth more than the same amount tomorrow

Systems Analyst

most responsible for analysis and design of information systems

Outsourcing

practice of turning over responsibility of some or all of an organization's information systems applications and operations to an outside firm

Technical feasibility

process of assessing the development organization's ability to construct a proposed system

Discount rate

rate of return used to compute the present value of future cash flows

Design

recommended solution is converted into logical and then physical system specifications

Tangible benefits

refer to items that can be measured in dollars and with certainty Examples include: reduced personnel expenses lower transaction costs, or higher profit margins.

Level-1 diagram

results from decomposition of Level-0 diagram.

Application Software

software designed to support organizational functions or processes

System Development Methodology

standard process followed in an organization to conduct all the steps necessary to analyze, design, implement, and maintain information systems.

1970s

system development becomes more like an engineering discipline

1990s

system integration, GUI applications, client/server platforms, Internet

Analysis

system requirements are studied and structured

a Fork

the beginning of parallel activities represented by a line with 2 arrows pointing out

a Join

the end of parallel activities represented by 2 arrows pointing to a horizontal line

Formal Systems

the official way a system works as described in organizational documentation (i.e. work procedure)

Informal Systems

the way a system actually works (i.e. interviews, observations)

1960s

third generation languages (3GL) faster and more reliable computers

Abstract use case

when a use case is initiated by another use case

Process

work or actions performed on data (inside the system)

"A ________ is a DFD that represents a system's major processes, data flows, and data stores at a high level."

Level-0 diagram

"Balancing is the conservation of inputs and outputs to a DFD process when that process is decomposed to a ________ level."

Lower

Agile Methodologies

Motivated by recognition of software development as fluid, unpredictable, and dynamic

A logical grouping of objects that have the same attributes and behaviors is known as a(n) ________.

Object class

Reuse is commonly applied to

Object-oriented development and Component-based development

Which feasibility is concerned with the project attaining its desired objectives?

Operational feasibility

"No process can have only ________. It would be making data from nothing. If an object has only that, then it must be a source."

Outputs

What is the practice of a company running a computer application for another organization?

Outsourcing

5 Phases in SDLC:

Planning Analysis Design Implementation Maintenance

The lowest level of a DFD is called a ________ data flow diagram.

Primitive

"A ________ is the work or actions performed on data so that they are transformed, stored, or distributed."

Process

Data cannot move directly from one data store to another data store. Data must be moved by a

Process

Current Physical

Process labels identify technology (people or systems) used to process the data. Data flows and data stores identify actual name of the physical media.

Current Logical

Physical aspects of system are removed as much as possible. Current system is reduced to data and processes that transform them.

System boundary

- Includes all the relevant use cases A boundary is the dividing line between the system and its environment Use cases are within the boundary Actors are outside of the boundary Represented as a box

Actor

- Is a role, not an individual Involved with the functioning of the system at some basic level Represented by stick figures

Use case

- represents a single system function - Represented as an ellipse

Name the 4 types of DFDs

Current Physical Current Logical New Logical New Physical

"________ solutions integrate individual traditional business functions into a series of modules so that a single transaction occurs seamlessly within a single information system rather than several separate systems."

ERP

Which of the below is NOT a true statement regarding the SDLC?

It is a rapid method to prototype and develop an application.

"Functional decomposition is a(n) ________ process of breaking the description of a system down into finer and finer detail, which creates a set of charts in which one process on a given chart is explained in greater detail on another chart."

Iterative

In which phase of the SDLC is an information system systematically repaired and improved?

Maintenance

Which of the following is NOT a source of requirements gathering for the systems analyst?

Market conditions

A DFD Diagram is balanced when

Number of inputs to lower level DFD equals number of inputs to associated process of higher-level DFD Number of outputs to lower level DFD equals number of outputs to associated process of higher-level DFD

"Systems development methodologies and techniques which are based on objects rather than data or processes are known as"

Object-oriented analysis and design

Which of the following is NOT a major category of sources of software?

Offshore

"A data flow cannot go directly back to the same process it leaves. There must be at least _______ other process(es) that handle(s) the data flow, produce(s) some other data flow, and return(s) the original data flow to the beginning process."

One

"If a company has a generic software need, they should consider acquiring its software from a(n) ________."

Packaged software producer

"In which design phase of the SDLC are logical specifications of the system from logical design transformed into technology-specific details from which all programming and system construction can be accomplished?"

Physical design

What is the first phase in the Systems Development Life Cycle?

Planning

The document sent to vendors asking them to propose hardware and software that will meet the requirements of your new system is called a

Request for proposal

"________ refers to the use of previously written software resources, especially objects and components, in new applications."

Reuse

Which type of feasibility deals with project duration?

Schedule feasibility

All of the following are categories of feasibility except ________.

Scope

"A ________ is the origin and/or destination of the data, and these are sometimes referred to as external entities because they are outside the system."

Source/Sink

Which of the following is NOT a consideration during the assessing technical feasibility stage?

System cost

Who has the primary responsibility for the design and analysis of information systems?

Systems analyst

"Most organizations find it beneficial to use a standard set of steps, called ________, to develop and support their information systems."

Systems development methodology

"A data flow is data that move together, so it can be composed of many individual pieces of data that are generated at the same time and that flow together to common destinations."

TRUE

"Although almost all systems development projects adhere to some type of life cycle, the exact location of activities and the specific sequencing of steps can vary greatly from one project to the next."

TRUE

"Computer-aided software engineering (CASE) tools were developed to make systems developers' work easier and more consistent."

TRUE

"Finding and fixing a software problem after the delivery of the system is often far more expensive than finding and fixing it during analysis and design."

TRUE

"The part of the design process that is independent of any specific hardware or software platform is referred to as logical design."

TRUE

Sources/sinks are sometimes referred to as external entities because they are outside the system.

TRUE

DFDs of new logical system are

Technology independent Show data flows, structure, and functional requirements of new system

When are forms most useful to the analyst?

When they contain organizational data

Data flow

arrows depicting movement of data

Balancing

conservation of inputs and outputs to a data flow diagram process when that process is decomposed to a lower level

Conservation Principle

conserve inputs and outputs to a process at the next level of decomposition

Source/sink

external entity that is the origin or destination of data (outside the system)

Level-n diagram

is a DFD diagram that is the result of n nested decompositions from a process on a level-0 diagram.

Level-0 diagram

is a data flow diagram that represents a system's major processes, data flows, and data stores at a high level of detail.

Extend relationship

is an association between two use cases where one adds new behaviors or actions to the other. Extends a use case by adding new behavior or actions Specialized use case extends the general use case.

Include relationship

is an association between two use cases where one use case uses the functionality contained in the other. Indicates a use case that is used (invoked) by another use case Links to general purpose functions, used by many other use cases

Connection

is an association between an actor and a use case. Depicts a usage relationship Connection does not indicate data flow Actors are connected to use cases with lines. Use cases are connected to each other with arrows.

Context diagram

is an overview of an organizational system that shows: the system boundaries external entities that interact with the system major information flows between the entities and the system Note: only one process symbol, and no data stores are shown

Data flow splitting

is when a composite data flow at a higher level is split and different parts go to different processes in the lower level DFD.

A Context data flow diagram (DFD) deliverable is

The Scope

The first page of the interview guide contains all of the following except ________.

The outcome of the interview

Cloud Computing

The provision of computing resources, including applications, over the Internet, so customers do not have to invest in the computing infrastructure needed to run and maintain the resources ex: google doc

"A(n) ________ is an external entity that interacts with a system and is someone or something that exchanges information with the systems."

Actor

In which phase of the SDLC are the system requirements studied and structured?

Analysis

"A data flow has a noun phrase label. More than one data flow noun phrase can appear on a single ________ as long as all of the flows on the same arrow move together as one package."

Arrow

According to the DFD conventions, the data flow is always depicted by a(n) ________.

Arrow

All of the following are ways of validating purchased software information, except

Asking the manufacturer if they feel their software is best

Use case

Is a depiction of a system's behavior or functionality under various conditions as the system responds to requests from users

What do DFDs of current systems do

Enable analysts to understand current logical and physical systems

Which of the following is an example of a tangible benefit?

Error reduction in data entry

Which of the following is NOT an example of open-source software?

Excel

"DFDs do a very good job of representing time. On a given DFD, there is an indication of whether a data flow occurs constantly in real time, once per week, or once per year. There is also an indication of when a system would run."

FALSE

Implementation is the final step of the traditional waterfall SDLC method.

FALSE

Process Modeling

Graphically represent the processes that capture, manipulate, store, and distribute data between a system and its environment and among system components. Utilize information gathered during requirements determination. Model processes and data structures.

"In which phase of the SDLC is the information system coded, tested, installed, and supported in the organization?"

Implementation

How does an organization rank criteria for choosing off the shelf software?

Importance depends on the organization's requirements.

"When an organization has the resources and a system must be built from scratch, an organization should choose what type of software?"

In-house development

"A(n) ________ arises when one use case uses another use case and is shown diagrammatically as a dotted-line arrow pointed toward the use case that is being used."

Include relationship

No process can have only ________ and if an object has only that, then it must be a sink.

Inputs


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