Chapter 10

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Development Processes

Chapter 10

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“We Need to Support Other Watches and
Mobile Devices, and at Least Android Phones.”


Need
to define and document business
procedures, train staff,
involve
other
partners


Make system
more generally
available


Strategic implication:
Spin
off PRIDE as
separate business?


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Study Questions

Q1:
How are
business processes
, IS, and
applications
developed?

Q2: How do organizations use business process
management
(BPM)?

Q3:
How is
Business Process Modeling Notation
used to model
processes?

Q4:
What are the
phases
in the
systems development life cycle
(SDLC
)?

Q5:
What are the keys for successful SDLC projects?

Q6:
How can
scrum
overcome the problems of the SDLC?

Q7:
2023
?


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Q1: How Are Business Processes, IS,

and Applications Developed?


Process of creating and maintaining information
systems


Requires:


Establishing system goals


Setting up the project


Determining requirements


Business knowledge and management skill

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Activities in a Business Process and the
Correlating Information Systems

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Relationship of Business Processes and
Information Systems

1.
Business processes, information systems, and applications have
different characteristics and components.

2.
Relationship of business processes to information systems is
many
-
to
-
many, or N:M.


A business process need not relate to any IS, but IS relates to
at least one business process.

3.
Every IS has at least one application because every IS has a
software component.

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Scope of Development Process

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Role of Development Personnel

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Q2: How Do Organizations Use Business
Process Management (BPM)?


Business process



Network of activities, repositories, roles,
resources, and data flows that interact to
accomplish a business function

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Why Do Processes Need Management?


Improve Process Quality


Change in Technology


Change in Business Fundamentals


Market (new customer category, change in customer
characteristics)


Product lines


Supply chain


Company policy


Company organization (merger, acquisition)


Internationalization


Business environment

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What Are BPM Activities?

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Q3: How Can BPMN Process Diagrams Help
Identify and Solve Process Problems?


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As
-
Is
Business
Order
Process:
Existing
Ordering
Process

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Check
Customer
Credit
Process

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Q4: What Are the Phases in the Systems
Development Life Cycle (SDLC)?

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Define System Goals and Scope

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SDLC: Requirements Analysis Phase

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Role of a Prototype


Provides user direct experience


Can be expensive to create


Parts often reused


Cost occurs early, sometimes before full
project funding available

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SDLC: Component Design Phase

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SDLC: Implementation Phase

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Conversion
types

1.
Pilot

2.
Phased

3.
Parallel

4.
Plunge

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Design and Implementation for the Five
Components

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SDLC: System Maintenance Phase

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Ethics Guide: Estimation Ethics


Estimating is just

theory”

average
of many
people’s
guesses.


Buy
-
in game


O
verly optimistic
schedules and
cost
estimates


At what point
is
buy
-
in within accepted
boundaries of
conduct?



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Ethics Guide: Estimation Ethics


Contractor agrees to produce system for less than
what will really be required


Time and materials contract


Fixed
-
cost contracts


In
-
house projects often started with buy
-
ins


Projects start with hopes of more money later


Team members disagree about costs. Do you report it?


Not all costs included in initial estimates. Report it?


Do you buy
-
in on project schedule if you can’t
make that schedule?

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Q5: What Are the Keys for Successful
SDLC Projects?


Create a work
-
breakdown structure.


Estimate time and costs.


Create a project plan.


Adjust plan via trade
-
offs.


Manage development challenges.

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Work
Breakdown

Structure

(WBS)

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Gantt Chart of the WBS for the Definition
Phase of a Project

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Gantt Chart with Resources Assigned

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Primary Drivers of Systems
Development

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Manage Development Challenges

1. Coordination

2. Diseconomies of scale

3. Configuration control

4. Unexpected events

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Difficulty of Requirements Determination


What specifically is system to do?


What, exactly, does the
report
doctors receive look like?


Will they have both a standard and exception report? Are
those reports fixed in structure or can
user
adapt them? If
so,
how?


How many practices and how many patients per practice
will PRIDE support?


How much cloud resource
needed?


Must create environment where difficult questions are
asked and answered.



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Changing Requirements


Systems development aims at moving target


The bigger system, the longer the project,
the more requirements change.


What should development team do?


Incorporate changes, build, complete and
make changes in maintenance phase?

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Scheduling and Budgeting Difficulties


How long to build it?


How long to create data model?


How long to build database applications?


How long to do testing?


How long to develop and document procedures?


How long for training?


How many labor hours? Labor cost?


What’s the rate of return on investment?

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Changing Technology


Do you want to stop your development to
switch to the new technology?


Would it be better to finish developing
according to the existing plan?


Why build an out
-
of
-
date system?


Can you afford to keep changing the
project?

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Diseconomies of Scale

Brooks’ Law


“Adding more people to a late project makes the
project later
.”


New staff must be trained by productive
members
who lose
productivity while
training.


Schedules
can be compressed only so
far.


Once
a project is late and
over budget
, no good
choice exists.


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Experiencing MIS InClass Exercise 10:
GardenTracker


Suppose you and two or three other students decide to open
a business that offers landscaping services. Your goal is to
develop a list of clients for whom you provide regular and
recurring services.


Need information system for tracking customers, services you
have provided, and services you are scheduled to provide in
the future.


As a new small business, you want a simple and affordable
system based on Excel or Access. The name of the system is
GardenTracker.


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Experiencing MIS InClass Exercise 10:
GardenTracker (cont’d)

1.
Explain
how you
would
use
SDLC
to
develop GardenTracker
.

2.
Define
the scope of your system.

3.
Explain
process you would use to
determine
feasibility of
GardenTracker
.

4.
List
data you need for such an assessment,
and explain how you might obtain or
estimate that data
.

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Q6: How Can Scrum Overcome the
Problems of the SDLC?

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Scrum
Essentials

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Scrum Process

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When Does Scrum End?


Customer is satisfied with product created
and accepts it.


Project runs out of time.


Project runs out of money.

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How Do Requirements Drive the Scrum
Process?

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Summary of Scrum Estimation
Techniques

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Q7: 2023

1.
Continuing focus on aligning business
processes and information systems with
business strategy, goals, and objectives

2.
Computer systems will be more easily
changed and adapted

3.
The cloud will lead to substantially more
innovation

4.
Emergence of new software vendor business
models


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Security Guide: Psst. There’s Another
Way, You Know . . .


Do you think servers in China were actually shut
down?


Large organizations with good IS departments that
had a firewall set up on port 24 to only allow traffic to
go to IP address of ISP did not lose any designs.


What about smaller organizations with minimal IS
Department, or supported by small, unsophisticated
VAR?

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Guide: The Real Estimation Process


Software developers are optimists.


People can’t work all the time.



Apply a factor like 0.6 to compute number of
effective labor hours for each employee.



Be aware of consequences of negotiating a
schedule.

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Active Review

Q1: How are business processes, IS, and applications
developed?

Q2: How do organizations use business process management
(BPM)?

Q3: How is Business Process Modeling Notation used to model
processes?

Q4: What are the phases in the systems development life cycle
(SDLC)?

Q5: What are the keys for successful SDLC projects?

Q6: How can scrum overcome the problems of the SDLC?

Q7: 2023
?

Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hal

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Case Study 10: Cost of PRIDE


T
ypical
example of a new software
venture


So
focused on
technology
and
making
it work
,
they neglect to consider what will happen,
longer term, if it is a success
.


Some
problem solutions involve
staff training
and
procedures.


L
onger
term, Flores and his partners need a
direction
.

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Sources of PRIDE Costs

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