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Sampling of Software Problems. Faye Starman gets an electric bill for $6.3 million instead of $63 due to a data entry errorSomeone is denied a new credit card because her Mother's credit history is merged with her ownSix people die due to excessive radiation from a therapeutic linear accelerator. More Sample Software Problems.
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1. Chapter 11
2. Sampling of Software Problems Faye Starman gets an electric bill for $6.3 million instead of $63 due to a data entry error
Someone is denied a new credit card because her Mothers credit history is merged with her own
Six people die due to excessive radiation from a therapeutic linear accelerator
3. More Sample Software Problems The Mars Climate Orbiter spacecraft crashes into the surface of Mars due to a simple unit-of-measure conversion error
Several Blackhawk helicopters crash killing several people due to radio signals interfering with on board computer systems
4. More Sample Software Problems $125 million is squandered on a hotel reservation system, in which proper project management should have revealed that this project was hopelessly out-of-control
Software development projects frequently produce systems that are not used because users deem them unusable
5. Preventing Horror Stories through Software Engineering Software engineering can address a significant number of the previously discussed software failures
Certain failures cannot be addressed by software engineering and proper system design, such as ensuring that users are adequately trained, but it can mitigate the effects of such problems
6. Preventing Horror Stories through Software Engineering Proper software engineering can address the following issues:
Adequate testing
Proper project management
Improved algorithm design
Improved data design
7. Therac-25 Case Study Divide into your software development teams to discuss the following:CaseStudy1.doc (distribute copy to class)
8. CONFIRM Development Objectives Design, develop, operate, and maintain a new state-of-the-art reservation processing system to be used world-wide.
Design and develop interfaces with airline reservation systems so consumers could make airline, hotel, and car rental reservations through a single computerized system.
9. CONFIRM Development Objectives Market the reservation system and other communications services to customers for profit.
Convert each of the partners' (Hilton, Marriot, and Budget Rent-A-Car) current reservation systems to the new integrated system.
Integrate the reservation systems with decision support systems.
10. CONFIRM Case Study: In October 1987 Marriott, Hilton, Budget Rent-a-car, and AMRIS form a consortium to develop and run CONFIRM, with AMRIS managing the development.
The project is to be developed in two phases and be completed by June 1992.
11. CONFIRM Case Study: On May 24, 1988, AMRIS announces the beginning of the CONFIRM design phase through a press release.
On December 30, 1988, AMRIS presents the base design of the system to to the members of the consortium. Marriott objects that the functional specifications are not sufficiently detailed to convey user needs to the developers.
12. CONFIRM Case Study: In March 1989, AMRIS presents a development plan which is found to be unacceptable by the consortium members.
In August 1989, AMRIS releases project financial estimates to consortium members. Based on these estimates, the other consortium members decide to remain involved in the project.
13. CONFIRM Case Study: The statements regarding the financial estimates are later found to severely underestimate personnel and operating costs.
In September 1989, AMRIS finally completes the design phase to the consortium members' satisfaction. The cost estimate for the project increases to $72.6 million from $55 million.
14. CONFIRM Case Study: In January 1990, AMRIS misses its first contractual deadline for completion of the terminal-screen design.
In February 1990, a second project milestone concerning analysis of the business area for the system is missed. AMRIS admits to being 13 weeks behind schedule, but claims that the original deadline can still be achieved.
15. CONFIRM Case Study: In February 1991, AMRIS presents the consortium members with a revised development plan that provides Marriott with its full functionality by March 1993. Marriott later claims that AMRIS knew it could not meet the new deadline and forced employees to artificially inflate their timetables or face firing or reassignment.
16. CONFIRM Case Study: In the revised development plan, AMRIS raises the price of the project to $92 million.
In October 1991, the president of AMRIS and about 20 additional employees resign.
17. CONFIRM Case Study: On May 1, 1992 the new president of AMRIS acknowledges that the "system interfaces and databases are insufficient to providing the necessary performance and reliability". He also attributes the situation to AMRIS's misrepresentation of the status of the project.
18. CONFIRM Case Study: Finally, in July 1992 after spending $125 million on the effort, the consortium disbands.
19. Questions for Discussion on the CONFIRM Case Study If you were a partner in the consortium developing CONFIRM, when would you have terminated your involvement and why?
Which SE deliverables should have been tell-tale indicators that the project was off-track?
Be specific. How would you evaluate a deliverable as being inadequate?
20. Questions for Discussion on the CONFIRM Case Study What violations of professional ethics occurred in the CONFIRM chronology?
If you were a developers on the CONFIRM project, would you have altered the time table as directed by management or face firing? What if you were economically dependent on this job?
21. Questions for Discussion on the CONFIRM Case Study No risk analysis was carried out on the project. What potential stumbling blocks might a thorough risk analysis have highlighted?
What suggestions to reduce the risk level of this development project might have been made?
As manager what would you have done differently?
22. Questions for Discussion on the CONFIRM Case Study The development plan scheduled meetings between the developers and user representatives only once a month? What problems might this cause? What sort of developer-user relationship would you establish for this project?
23. Questions for Discussion on the CONFIRM Case Study If you were interviewing with a company that appeared to have an excessive number of openings, what questions might you ask as a result of being familiar with the CONFIRM case study?
What questions would you ask a potential employer, If you were considering being hired as a developer for a large-scale project?