systems analysis and design allen dennis and barbara haley text

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4 - 1 Systems Analysis Systems Analysis and Design, and Design, 2 2 nd nd Edition Edition Alan Dennis and Barbara Haley Wixom John Wiley & Sons, Inc. Slides by Roberta M. Roth University of Northern Iowa

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4 - 1

Systems Analysis Systems Analysis and Design, and Design, 22ndnd Edition Edition

Alan Dennis and Barbara Haley WixomJohn Wiley & Sons, Inc.

Slides by Roberta M. Roth University of Northern Iowa

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Requirements Requirements DeterminationDetermination

Chapter 4Jerry Fjermestad

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Key Definitions

The As-Is system is the current system and may or may not be computerizedThe To-Be system is the new system that is based on updated requirementsThe System Proposal is the key deliverable from the Analysis Phase

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Key Ideas

The goal of the analysis phase is to truly understand the requirements of the new system and develop a system that addresses them -- or decide a new system isn’t needed.The System Proposal is presented to the approval committee via a system walk-through.Systems analysis incorporates initial systems design.Requirements determination is the single most critical step of the entire SDLC.

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REQUIREMENTS REQUIREMENTS DETERMINATIONDETERMINATION

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A statement of what the system must do A statement of characteristics the system must haveFocus is on business user needs during analysis phaseRequirements will change over time as project moves from analysis to design to implementation

What is a Requirement?

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Functional RequirementsA process the system hast to performInformation the system must contain

Nonfunctional RequirementsBehavioral properties the system must have

OperationalPerformanceSecurityCultural and political

Requirement Types

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Requirements definition reportText document listing requirements in outline formPriorities may be included

Key purpose is to define the project scope: what is and is not to be included.

Documenting Requirements

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Determining Requirements

Participation by business users is essentialThree techniques help users discover their needs for the new system:

Business Process Automation (BPA)Business Process Improvement (BPI)Business Process Reengineering (BPR)

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Basic Process of Analysis (Determining Requirements)

Understand the “As-Is” systemIdentify improvement opportunitiesDevelop the “To-Be” system conceptTechniques vary in amount of change

BPA – small changeBPI – moderate changeBPR – significant change

Additional information gathering techniques are needed as well

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REQUIREMENTS REQUIREMENTS ANALYSIS ANALYSIS TECHNIQUESTECHNIQUES

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Business Process Automation

Goal:

Efficiency for users

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Identifying Improvements in As-Is Systems

Problem AnalysisAsk users to identify problems and solutionsImprovements tend to be small and incrementalRarely finds improvements with significant business value

Root Cause AnalysisChallenge assumptions about why problem existsTrace symptoms to their causes to discover the “real” problem

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Root Cause Analysis Example

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Business Process Improvement

Goal:

Efficiency andeffectivenessfor users

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Duration AnalysisCalculate time needed for each process stepCalculate time needed for overall processCompare the two – a large difference indicates a badly fragmented processPotential solutions:

Process integration – change the process to use fewer people, each with broader responsibilitiesParallelization – change the process so that individual step are performed simultaneously

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Activity-Based Costing

Calculate cost of each process stepConsider both direct and indirect costsIdentify most costly steps and focus improvement efforts on them

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Benchmarking

Studying how other organizations perform the same business processInformal benchmarkingCommon for

customer-facing processesInteract with other business’ processes as if you are a customer

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Business Process Reengineering

Goal:

Radical redesign of business processes

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Outcome Analysis

Consider desirable outcomes from customers’ perspectiveConsider what the organization could enable the customer to do

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Technology Analysis

Analysts list important and interesting technologiesManagers list important and interesting technologiesThe group identifies how each might be applied to the business and how the business might benefit

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Activity Elimination

Identify what would happen if each organizational activity were eliminatedUse “force-fit” to test all possibilities

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Your Turn

How do you know whether to use business process automation, business process improvement, or business process reengineering? Provide two examples.

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Selecting an Analysis Technique

Potential business valueProject costBreadth of analysisRisk

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Characteristics of Analysis Techniques

Business Business BusinessProcess Process ProcessAutomation Improvement Reeingineering

Potential Business Low-Moderate Moderate HighValue

Project Cost Low Low-Moderate High

Breadth of Analysis Narrow Narrow-Moderate Very Broad

Risk Low-Moderate Low-Moderate Very High

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REQUIREMENTS-REQUIREMENTS-GATHERING GATHERING TECHNIQUESTECHNIQUES

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Interviews

Most commonly used techniqueBasic steps:

Selecting IntervieweesDesigning Interview QuestionsPreparing for the InterviewConducting the InterviewPost-Interview Follow-up

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Selecting Interviewees

Based on information needsBest to get different perspectives

ManagersUsersIdeally, all key stakeholders

Keep organizational politics in mind

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Types of Questions

Types of Questions Examples

Closed-Ended Questions * How many telephone orders are received per day?

* How do customers place orders?* What additional information would you like the new system to provide?

Open-Ended Questions * What do you think about the current system?* What are some of the problems you face on a daily basis?* How do you decide what types of marketing campaign to run?

Probing Questions * Why?* Can you give me an example?* Can you explain that in a bit more detail?

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Organizing Interview Questions

Unstructured interview useful early in information gathering

Goal is broad, roughly defined information

Structured interview useful later in process

Goal is very specific information

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Structuring the Interview

High Level:Very General

Medium-Level:ModeratelySpecific

Low-Level:Very Specific

TOP DOWN

BOTTOM UP

EXAMPLES?

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Interview Preparation Steps

Prepare general interview planList of questionAnticipated answers and follow-ups

Confirm areas of knowledgeSet priorities in case of time shortagePrepare the interviewee

ScheduleInform of reason for interviewInform of areas of discussion

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Conducting the Interview

Appear professional and unbiasedRecord all informationCheck on organizational policy regarding tape recordingBe sure you understand all issues and termsSeparate facts from opinionsGive interviewee time to ask questionsBe sure to thank the intervieweeEnd on time

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Conducting the InterviewPractical Tips

Take time to build rapportPay attentionSummarize key pointsBe succinctBe honestWatch body language

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Post-Interview Follow-Up

Prepare interview notesPrepare interview reportHave interviewee review and confirm interview reportLook for gaps and new questions

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Joint Application Development

A structured group process focused on determining requirementsInvolves project team, users, and management working togetherMay reduce scope creep by 50%Very useful technique

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JAD Participants

FacilitatorTrained in JAD techniquesSets agenda and guides group processes

Scribe(s)Record content of JAD sessions

Users and managers from business area with broad and detailed knowledge

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JAD Sessions

Time commitment – ½ day to several weeksStrong management support is needed to release key participants from their usual responsibilitiesCareful planning is essentiale-JAD can help alleviate some problems inherent with groups

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JAD Meeting Room

JPEG Figure 5-5 Goes Here

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The JAD Session

Formal agenda and ground rules Top-down structure most successfulFacilitator activities

Keep session on trackHelp with technical terms and jargonRecord group inputStay neutral, but help resolve issues

Post-session follow-up report

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Managing Problems in JAD Sessions

Reducing dominationEncouraging non-contributorsSide discussionsAgenda merry-go-roundViolent agreementUnresolved conflictTrue conflictUse humor

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JAD

JAD origins: IBM late 1970'shas flourished outside of the academic community (like Case)

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JAD

The Generations of JADFrom Carnel, Et Al., (1993) CACM, 36(4) 40-48

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Questionnaires

A set of written questions, often sent to a large number of peopleMay be paper-based or electronicSelect participants using samples of the populationDesign the questions for clarity and ease of analysisAdminister the questionnaire and take steps to get a good response rateQuestionnaire follow-up report

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Good Questionnaire Design

•Begin with non-threatening and interesting questions•Group items into logically coherent sections•Do not put important items at the very end of the questionnaire•Do not crowd a page with too many items•Avoid abbreviations•Avoid biased or suggestive items or terms•Number questions to avoid confusion•Pretest the questionnaire to identify confusing questions•Provide anonymity to respondents

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Document Analysis

Study of existing material describing the current systemForms, reports, policy manuals, organization charts describe the formal systemLook for the informal system in user additions to forms/report and unused form/report elementsUser changes to existing forms/reports or non-use of existing forms/reports suggest the system needs modification

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Observation

Watch processes being performedUsers/managers often don’t accurately recall everything they doChecks validity of information gathered other waysBe aware that behaviors change when people are watchedBe unobtrusiveIdentify peak and lull periods

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Selecting the Appropriate Requirements-Gathering Techniques

Type of informationDepth of informationBreadth of informationIntegration of informationUser involvementCostCombining techniques

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Selecting the Appropriate Techniques

Interviews JAD Questionnaires Document Observation Analysis

Type of As-Is As-Is As-Is As-Is As-IsInformation Improve. Improve. Improve. To-Be To-Be

Depth of High High Medium Low LowInformation

Breadth of Low Medium High High LowInformation

Integration Low High Low Low Lowof Info.

User Medium High Low Low LowInvolvement

Cost Medium Low- Low Low Low- Medium Medium

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Summary

The analysis process focuses on capturing the business requirements for the systemFunctional and non-functional business requirements tell what the system must doThree main requirements analysis techniques are BPA, BPI, and BPRThese techniques vary in potential business value, but also in potential cost and risk

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Summary, continued

There are five major requirements-gathering techniques that all systems analysts must be able to use: Interviews, JAD, Questionnaires, Document Analysis, and Observation.Systems analysts must also know how and when to use each as well as how to combine methods.