Content
Chapter 6
Determining System
Requirements
9
Requirements determination
9
Data collection methods
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© 2011 by Prentice Hall: J.A.Hoffer et.al., Modern Systems Analysis & Design, 6th Edition
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interview
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observation & document analysis
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Joint Application Design (JAD)
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Prototype
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Questionnaire
Explain how computing can support requirements
determination
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1. Performing Requirements Determination
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1.1 Process of Determining Requirements
„
Systems Analyst Characteristics for Successful
Requirements Determination
Impertinence:
Impartiality:
find best solution
Relaxing
constraints: assume every thing is possible
Attention
to details: find all facts
Reframing:
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question everything
new create process
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2. Traditional Methods for Determining
Requirements
1.2 Deliverables and Outcomes
„
Deliverables for Requirements Determination
„ Interviewing
(individuals & groups)
„ Observing workers
„ Studying business documents
„ Questionnaire *
From
interviews and observations - interview
transcripts, observation notes, meeting minutes
From existing written documents - mission and
strategy statements, business forms, procedure
manuals, job descriptions, training manuals, system
documentation, flowcharts
From computerized sources – Joint Application
Design session results, CASE repositories, reports
from existing systems, displays and reports from
system prototype
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2.1 Interviewing and Listening
Guidelines for Effective Interviewing
„ One
Interview Guideline
of the primary ways analysts gather
information about an IS project
„ Interview guide is a document for
developing, planning and conducting an
interview
„
Plan the interview
Prepare
interviewee: appointment, priming questions
Prepare agenda, checklist, questions
„
„
„
„
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Listen carefully and take notes (tape record if
permitted)
Review notes within that day.
Be neutral
Seek diverse views
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Choosing Interview Questions
Interview Outline
„
Each question in an interview guide can
include verbal & non-verbal information
Open-ended
questions: questions that have no prespecified answers
Closed-ended questions: questions that ask those
responding to choose from among a set of
specified responses
„
T/F
Multiple choice
„ Rating a response
„
„
Ranking items
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2.2 Interviewing Groups
Interviewing Groups (Cont.)
„ Drawbacks
„ Interview
to individual interviews
Contradictions
several key people together
„ Advantages
and inconsistencies between
interviewees
Follow-up
More
effective use of time
Can hear agreements and disagreements at once
Opportunity for synergies
discussions are time consuming
New
interviews may reveal new questions
that require additional interviews with those
interviewed earlier
„ Disadvantages
More
difficult to schedule than individual
interviews
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2.3 Directly Observing Users
Nominal Group Technique (NGT)
„
„
A facilitated process that supports idea generation by
groups
Process
„
Direct Observation
Watching
users do their jobs
Members
come together as a group, but initially work
separately
Each person writes ideas
Facilitator reads ideas out loud, and they are written on a
blackboard or flipchart
Group openly discusses the ideas for clarification
Ideas are prioritized, combined, selected, reduced
„
Obtaining
more firsthand and objective
measures of employee interaction with IS
(negative)
Can cause people to change their
normal operating behavior
Time-consuming
NGT exercise used to complement group meetings or
as part of JAD effort
and limited time to
observe
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2.4 Analyzing Procedures and Other
Documents
„
Types of information to be discovered
Problems
Document Analysis
Review
of existing business documents
Can give a historical and “formal” view of system
requirements
„
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Useful document: work procedure/ form /
report
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
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with existing system
Opportunity to meet new needs
Organizational direction
Titles and names of key individuals
Values of organization
Special information processing circumstances
Reasons for current system design
Rules for processing data
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Analyzing Procedures and Other
Documents (Cont.)
a)
User document:
a written work
procedure
„
Potential Problems with Procedure Documents
May
involve duplication of effort
May
have missing procedures
May
be out of date
May
contradict information obtained through
interviews
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Analyzing Procedures and Other
Documents (Cont.)
„
b)
User document:
a business form
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)
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Comparison of Observation and Document Analysis
c)
User document:
a report
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3. Contemporary Methods for
Determining System Requirements
„
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3.1 Joint Application Design (JAD)
Joint Application Design (JAD)
„
Intensive group-oriented requirements
determination technique
„
Team members meet in isolation for an
extended period of time
„
Highly focused
„
Resource intensive
Brings
together key users, managers, and systems
analysts
Purpose: collect system requirements
simultaneously from key people
Conducted off-site
„
Group Support Systems
Facilitate
sharing of ideas and voicing of opinions
about system requirements
CASE/ Prototype
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JAD (Cont.)
JAD (Cont.)
„
JAD Participants:
Session
Users:
„
Leader: facilitates group process.
Documentation
active, speaking participants
Managers:
detailing
existing
system (AS-IS)
Features of
proposed
system (TO-BE)
active, speaking participants
Sponsor:
high-level champion, limited
participation.
Systems
Scribe:
IS
End Result
Analysts: should mostly listen.
record session activities.
Staff: should mostly listen.
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3.3 Using Prototyping during Requirements
Determination
3.2 Upper CASE Tools during JAD
„
Used to analyze existing systems
„
Help discover requirements to meet changing
business conditions
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Iterative development process
„ Elementary working version of system is built
„
Quickly
converts requirements to working version
of system
Enables
analysts to enter system models
directly into CASE during the JAD session
„
Screen
designs and prototyping can be done
during JAD and shown to users
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Refine understanding of system requirements
in concrete terms
Once
the user sees requirements converted to
system, will ask for modifications or will generate
additional requests
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Using Prototyping During Requirements
Determination (Cont.)
„
Using Prototyping During Requirements
Determination (Cont.)
Most useful when
User
requests are not clear
Few
users are involved in the system
Designs
„
Tendency
Difficult
are complex and require concrete form
to avoid formal documentation
to adapt to more general user audience
Sharing
data with other systems is often not
considered
History
of communication problems between
analysts and users
Tools
Drawbacks
Systems
Development Life Cycle (SDLC)
checks are often bypassed
are readily available to build prototype
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4. Radical Methods for Determining
System Requirements
„
4.1 Identifying Processes to Reengineer
„
Business Process Reengineering (BPR)
Key business processes
Structured,
measured set of activities designed to
produce specific output for a particular customer
or market
Search
for, and implementation of radical change
in business processes to achieve breakthrough
improvements in products and services
„
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Focused
BPR Goals
on customers and outcome
Reorganize
complete flow of data in major
sections of an organization
Eliminate unnecessary steps / Combine steps
Become more responsive to future change
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Disruptive Technologies (Cont.)
4.2 Disruptive Technologies
„
Technologies that enable the breaking of longheld business rules that inhibit organizations
from making radical business changes
„
Information technologies must be applied to
radically improve business processes
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5. Requirements Determination using
Agile Methodologies
„
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5.1 Continual User Involvement
Continual user involvement
Replace
traditional SDLC waterfall with iterative analyze –
design – code – test cycle
„
Agile usage-centered design
Focuses
„
on user goals, roles, and tasks
Planning Game from eXtreme programming
Based
on eXtreme programming
Exploration, steering, commitment
FIGURE 6-11
The iterative analysis–design–code–test
cycle
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5.3 Planning Game from eXtreme Programming
5.2 Agile Usage-Centered Design: Steps
„
Gather a group of people: users, programmers, analysts,
testers, facilitator
„
Document complaints of current system
„
Determine important user roles
„
Determine, prioritize, and describe tasks for each user role
„
Group similar tasks into interaction contexts
„
Give description of each interaction context
„
Associate each interaction context with a user interface for
the system, and prototype the interaction context
„
Step through and modify the prototype
FIGURE 6-12
eXtreme Programming’s Planning Game
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6 e-Commerce Applications: Determining
System Requirements
„
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Summary
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Determining system requirements for Pine
Valley furniture’s Webstore
System
layout and navigation characteristics
Webstore
and site management system capabilities
Customer
and inventory information
System
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Observing workers and business documents
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Questionnaire
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Interviews
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Prototyping
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Joint Application Design
9
Explain how computing can provide support for
requirements determination
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Understand how requirements determination
techniques apply to the development of e-Commerce
applications
prototype evolution
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Requirements Elicitation
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Quiz
Questions & Answers
1 _________________________ is the search for,
and implementation of, radical change in business
processes to achieve breakthrough improvements
in products and services.
2 __________________ are questions in interviews
that have no pre-specified answers.
3 The structured, measured set of activities designed
to produce a specific output for a particular
customer or market is called _________________
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Exercise
1 Describe traditional techniques for collecting
information during analysis. When might one
be better than another?
2 What is JAD? How is it better than traditional
information gathering techniques? What is its
weaknesses?
3 Describe how prototyping can be used during
requirements determination. How is it better or
worse than traditional methods?
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