Chapter 10 Information Systems Development. Fox Lakes facilities cant handle wedding crowds....
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Transcript of Chapter 10 Information Systems Development. Fox Lakes facilities cant handle wedding crowds....
Chapter 10
Information Systems Development
Fox Lake’s facilities can’t handle weddin
g crowds.
Problems sharing
facilities, timely
maintenance, and tracking repairs.
Didn’t know how
wedding business
would impact
everything else.
Business
analyst, Laura, comes to help
This Could Happen To You: “You’re Not Going to Take Your Bridal Gown into a Porta Potty”
10-2Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Scenario video
Q1: What is systems development?
Q2: Why is systems development difficult and risky?
Q3: What are the five phases of the SDLC?
Q4: How is system definition accomplished?Q5: What is the users’ role in the requirements
phase?Q6: How are the five components designed?
Q7: How is an information system implemented?
Q8: What are the tasks for system maintenance?
Q9: What are some of the problems with the SDLC?How does the knowledge in this chapter help Fox Lake and you?
Study Questions
10-3Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Process of creating and maintaining information systems
Involves all five IS components
Q1: What Is Systems Development?
10-4Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Many projects never finished. Those that finish often 200–300% over budget.
Some projects finish within budget and schedule, but never satisfactorily accomplish their goals.
Q2: Why Is Systems Development Difficult and Risky?
10-5Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Five Major Challenges to Systems Development
10-6Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Difficult to determine requirements•What specifically is system to do? •How does wedding planner use new system to reserve a
room or building? •What does data entry screen look like? •How does planner add/reduce facilities once wedding
scheduled? •What should system do when a wedding is cancelled? •Facility schedule system interface with accounting
systems? How? •Does system need to reserve floor or refrigerator space
in restaurant kitchen?Must create environment where difficult questions are asked and answered.
Q2: Why Is Systems Development Difficult and Risky? (cont’d)
10-7Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Changing requirements• Large, long projects aim at moving
targetScheduling 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?
Q2: Why Is Systems Development Difficult and Risky? (cont’d)
10-8Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Changing Technology
Q2: Why Is Systems Development Difficult and Risky? (cont’d)
10-9Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
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?
Diseconomies of scale• Brooks’ Law
“Adding more people to a late project makes the project later.”
Q2: Why Is Systems Development Difficult and Risky? (cont’d)
10-10Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
New staff must be trained by productive members who lose productivity while training new members.
Systems development is challenging, but solid methodologies exist that are successful when supported and managed properly.Systems development life cycle (SDLC), most common process for systems development.
Is It Really So Bleak?
10-11Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Yes and No
Q3: What Are the Five Phases of the SDLC?
10-12Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Based on problem analysis and decision solving processes
Q4: How Is System Definition Accomplished?
10-13Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
• Team of users and IT professionals
• Small business may hire consultant to work with managers and key employees
• Fox Lake: Jeff, Laura, Mike, Anne, and other key employees will define system
• Purpose: Increase revenue from wedding events
• Goals: Eliminate or at least reveal schedule conflicts and improve maintenance tracking
• Scope: Specify users or business processes that will be involved, or facilities, functions, events that will be involved
Define scope for new Fox
Lake system
Q4: How Is System Definition Accomplished? (cont’d)
10-14Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Cost feasibility•Approximated, “back-of-the-envelope” analysis•Purpose: eliminate infeasible ideas early•Consider cost of previous projects, operational and labor
costsSchedule feasibility
•Ball park estimate
Technical feasibility• Do we have the hardware, software, personnel, expertise to complete project?
Organizational feasibility•Fits customs, culture, charter, legal requirements of
organization
Assess Feasibility: Dimensions of Feasibility
10-15Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Typical team• Systems analyst and/or business analyst• Managers• Programmers• Software testers• Users
Team composition changes over time
Active user involvement is critical throughout
Form a Project Team
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Review and approve requirements
Q5: What Is the Users’ Role in the Requirements Phase?
10-17Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Laura only person with knowledge of systems development, she will work with development contractor to help specify Fox Lake’s needs
Suppose that you and two or three other students have been groundskeepers at Fox Lake, and you have decided to go out on your own and open a business that offers landscaping services. Your goal is to develop a list of clients for whom you provide regular and recurring services, such as mowing, weeding, and pool cleaning, as well as specialty services, such as pruning, garden preparation, tree removal, sprinkler installation and repair, and the like.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 GardenTraker.
Experiencing MIS InClass Exercise 10: GardenTraker
10-18Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
1. Explain how you would use the SDLC to develop GardenTraker.
2. Define the scope of your system.3. Explain the process you would use to determine
the feasibility of GardenTraker. List data you need for such an assessment, and explain how you might obtain or estimate that data.
Experiencing MIS InClass Exercise 10: GardenTraker (cont’d)
10-19Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
4. Consider just the tracking of recurring services, and list all of the requirements that you can imagine for that functionality. Be specific and answer at least the following:a. What data will you need?b. How will you input that data? Show a mockup of a
data entry screen, and describe how it will be used.c. Using your mockup, describe how you will modify
recurring service data.d. Using your mockup, describe how you will cancel a
recurring service.e. Specify any other requirements you believe are
important for tracking recurring services.
Experiencing MIS InClass Exercise 10: GardenTraker (cont’d)
10-20Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
5.Present your answers to item 4 to the rest of the class and obtain feedback from your classmates.
6. Modify your answer to item 4 based upon feedback you received in item 5.
7. Considering just the recurring services functionality, do you think it would be better to use Excel or Access for this project? List the criteria you used to answer that question. Summarize the consequences of making a poor choice between these two products.
8. What does this short exercise tell you about information systems development? Answer this question in such a way that you could use your answer to demonstrate your critical-thinking skills in a job interview
Experiencing MIS InClass Exercise 10: GardenTraker (cont’d)
10-21Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Determine hardware specifications• Purchase it, lease it, or lease time from hosting
serviceDetermine software specifications • Off-the-shelf, custom developed
Database design• Convert data model to a database design
Q6: How Are the Five Components Designed?
10-22Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Procedure design• Normal, backup, and failure recovery
proceduresDesign Job Descriptions• Create and define new tasks and
responsibilities
• Figure 10-7
Procedures to Be Designed
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Teams of systems analysts and users determine job descriptions and functions
Duties and responsibilities for new jobs and revised jobs coordinated with human resources policies
Design of Job Descriptions
10-24Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Q7: How Is an Information System Implemented?
10-25Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
System testing
Test plan
Product Quality Assurance (PQA)
User testing Develop test plans and test cases Final say on whether system is “production
ready”
Beta testing
Q7: How Is an Information System Implemented? (cont’d)
10-26Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Design and Implementation for the Five IS Components
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System Conversion Approaches
10-28Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Pilot
•Implement entire system in limited portion of business
•Advantage: Limits exposure to business if system fails
Phased•System installed in phases or modules•Each piece is installed and tested
Parallel•Complete new and old systems run simultaneously
•Very safe, but expensive
Plunge (“Big Bang”)
•High risk if new system fails, no fall back system
•Only used if new system not vital to company operation
Q8: What Are the Tasks for System Maintenance?
10-29Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Failure is a difference between what system does and what it is supposed to do.
• Sequence of non-repeated phases
• It rarely works smoothly, causing development team to go back and forth, raising costs and delaying project
SDLC Waterfall Method
• Business requirements change• “Analysis paralysis”—projects
spend so much time on documentation it hampers progress
Requirements
documentation difficulty
• Time and cost estimates for large project usually way off
• People who make initial estimates know little about how long it will take or cost
Scheduling and
budgeting difficulties
Q9: What Are Some of the Problems with the SDLC?
10-30Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
SDLC Waterfall Method
10-31Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Fox Lake teams needs to know:• Basic process for creating and information system• Importance of defining scope• To ask for a feasibility assessment up front • Difficulty (and importance) of providing accurate
requirements
You• At some point in your career, you will be
running a business unit or a department or a project that needs an information system. You will need to know how to proceed, and knowledge in this chapter will get you started on right path
How Does the Knowledge In This Chapter Help Fox Lake and You?
10-32Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Active Review
10-33Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Q1: What is systems development?
Q2: Why is systems development difficult and risky?
Q3: What are the five phases of the SDLC?
Q4: How is system definition accomplished?Q5: What is the users’ role in the requirements
phase?Q6: How are the five components designed?
Q7: How is an information system implemented?
Q8: What are the tasks for system maintenance?
Q9: What are some of the problems with the SDLC? How does the knowledge in this chapter help Fox Lake and you?
Contractor agrees to produce system for less than what will really be required• Time and materials contracts• Fixed-cost contracts
In-house projects are often started with buy-ins
• Projects often start with hopes of more money later• Team members disagree about costs. Do you report
it? • Not all costs included in initial estimates. Do you
report it?Do you buy-in on project schedule if you can’t make that schedule?
Ethics Guide: Estimation Ethics
10-34Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Estimating is just “theory”—average of many people’s guesses
Project managers take estimates to managementManagement negotiates schedule and budget by reducing time by a month or two, which negatively impacts project
Projects start with optimistic schedules and ends up late
Developers begin to not take project deadlines seriously
Guide: The Real Estimation Process
10-35Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
1974 study of the causes of information systems failures.
• Most important factor: Lack of user involvement. • Second: Unclear, incomplete, and inconsistent
requirements.
“The CHAOS Report” (1994)
• Leading causes of IS failure are, in descending order: (1) lack of user input, (2) incomplete requirements and specifications, and (3) changing requirements and specifications
Case Study 10: Slow Learners, or What?
10-36Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
University of Maryland study (2004) analyzed 19 system failures to determine their cause.
•Results indicate causes of system failure: (1) poor requirements definition; (2) failure to communicate with users.
IRS Oversight Board (2003): Primary cause of IRS BSM failure was inadequate business unit ownership and sponsorship of projects, which led to unrealistic business cases and continuous project scope creep.
Case Study 10: Slow Learners, or What? (cont’d)
10-37Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Case Study 10: Slow Learners, or What? (cont’d)
10-38Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
For over 35 years, studies have
consistently shown that leading causes of
system failures are:
Lack of user involvement
Incomplete and
changing requirement
s
Many businesses
ignore lessons from decades of research
about causes of IS failures
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mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. Printed in the United States of America.
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall