CS 501: Software EngineeringAdministrationSlide 3Slide 4Feasibility StudyWhy are Feasibility Studies Difficult?The Decision Maker's ViewpointThe Decision Maker's Viewpoint Where are risks? Can they be minimized?Example 1: U.S. Government Agency (Decision before Feasibility Study)Example 1: ChronologyExample 1: National Academy ReportNational Academy Report: Technical RecommendationsExample 1: Prototype and Phased DevelopmentExample 1: Obvious ProblemsExample 1: DilemmaFeasibility Study: ScopeExample 2: Library of Congress Confusion over ScopeFeasibility Study: BenefitsExample 3: Benefits of the National Science Digital Library (NSDL)Example 3: NSDL TimetableFeasibility Study: TechnicalFeasibility Study: Planning and ResourcesFeasibility Study: Alternatives and RisksTechniques for Feasibility StudiesFeasibility ReportCS 501: ClientCS 501: ResourcesCS 501: ObstaclesCS 501: How to Minimize Risk?CS 501: Feasibility Report1CS 501 Spring 2005CS 501: Software EngineeringLecture 3Feasibility Studies2CS 501 Spring 2005AdministrationProject teams: • If you have definitely chosen a project and reached agreement with your client, send email to [email protected] with the names of your team members• If you do not have a team you can meet after class• We may ask teams to add extra members• A Teaching Assistant will be added to each team.3CS 501 Spring 2005AdministrationNews group:newsstand.cit.cornell.edu/cornell.class.cs501Course team mailing [email protected](Do not subscribe)Assignment 1: due dateFriday, February 18, 5:00 p.m. (corrects mistake on Web site)4CS 501 Spring 2005AdministrationProject teams:If you are having difficulty finding a team send email to [email protected]:Announcements by project groups5CS 501 Spring 2005Feasibility StudyA feasibility study is a study made before committing to a project.A feasibility study leads to a decision:go aheaddo not go aheadthink againIn production projects, the feasibility study often leads to a budget request.In research, a feasibility study is often in the form of a proposal.6CS 501 Spring 2005Why are Feasibility Studies Difficult?Benefits are usually very hard to quantify.Approach is usually ill-defined. Estimates of resources needed and timetable are very rough.(e.g., eCornell)Organizational changes may be needed.(e.g., Copyright deposit system.)Therefore, feasibility studies rely heavily on the judgment of experienced people. Who are often over-enthusiastic.Mistakes made at the beginning are the most difficult to correct.7CS 501 Spring 2005The Decision Maker's ViewpointA senior member of an organization must decide whether to begin a major software project. What information is needed?Client: Who is this project for?Scope: What are the boundaries of the project?Benefits: What are the benefits? Can they be quantified?Technical: Is there at least one technical way to carry out the project?Resources: What are the estimates of staff, time, equipment, etc?Alternatives: What are the options if the project is not begun?8CS 501 Spring 2005The Decision Maker's ViewpointWhere are risks? Can they be minimized?Technical• There must be an outline plan with a rough timetable and staff allocation.• The plan must have a very large margin for contingencies. (Projects typically require twice the staff and/or time envisaged in the feasibility plan.)External• Every system interacts with others. Are the others committed to the necessary efforts?• Where are the external pressures and obstacles?9CS 501 Spring 2005Example 1: U.S. Government Agency(Decision before Feasibility Study)Outline DescriptionA U.S. government agency, which manages huge numbers of documents and other records, has been very slow in moving from a paper based approach to managing digital documents.10CS 501 Spring 2005Example 1: Chronology•A scientific computing center at University of California was commissioned to develop a prototype system to demonstrate technology.•Funds were approved by Congress to "procure" a major computer system.•The National Academy of Sciences was commissioned to report on the technical approach to be followed and the results of the University of California prototype (feasibility study).Note: The decision to go ahead was made and the budget approved before the feasibility study was begun.11CS 501 Spring 2005Example 1: National Academy ReportThe National Academy study finds:•The computer system is technically feasible.•The University of California prototype is promising but incomplete.•Agency needs stronger technical staff.The study was not asked to comment on external factors, but discovered major weaknesses in the agency's management structure and organizational skills.12CS 501 Spring 2005National Academy Report:Technical RecommendationsThe study recommends a phased approach:1. System architecture created by iterative refinement to create a Phase 1 design.2. Followed by sequential implementation using the Phase 1 design[Note that this is the same phasing used in the vector graphics for Basic project discussed in Lecture 2.]13CS 501 Spring 2005Example 1: Prototype and Phased Development•A prototype is not released to users, except experimentally•In phased development, each phase is released into full productionUC prototypeBuild phase 1Build phase 2Demonst-ration onlyPhase 1 productionPhase 2 productionDevelopersUsersIterative processSequential process14CS 501 Spring 2005Example 1: Obvious ProblemsOrganizational:•Agency senior management clearly not ready to lead a very large project that will completely change the agency•No thought given to the workflow and job changes that will affect almost every member of staffPreparation:•No preliminary study made of volumes or kinds of data; nor of the very complex access policiesComplexity•Major changes in the requirements and design are inevitable once the system goes into production and has real users15CS 501 Spring 2005Example 1: Dilemma•Agency does not want to return money to Congress•National Academy study was paid for by agency and restricted to technical considerations•The fundamental problem lies at the senior management level[A phased approach over many years might possibly work, but only after the organizational problems are addressed.]•The agency has adopted a pure waterfall model and put out a Request for Proposal for the RequirementsThis is a disaster in the making.16CS 501 Spring 2005Feasibility
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