Ch5new10 - Chapter 5 Determining System Requirements D...

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Unformatted text preview: Chapter 5: Determining System Requirements D. Harrison McKnight Eli Broad College of Business Business How Requirements Determination Really Works How ESSENTIAL 2 Know Key terms – Explain why requirements Explain determination is so difficult determination – Concepts in Victor-Cooprider model – 3 ways BPR affects requirements – Pros and Cons of requ’s. methods: Pros – interviewing, observation, questionnaire, JAD, prototyping, document analysis prototyping, Determining System Specifications: A Critical Phase Relative Cost to Fix an Error Phase Error Found Phase Requirements Requirements Design Design Coding Coding Developer Testing Developer Customer Testing Customer Operation Operation Cost Ratio Cost 1 3-6 10 15-40 30-70 40-1000 40-1000 Determining System Specifications: A Critical Phase Determining System Specifications: Very Tough Communication Issues Communicating across Barriers Requirements Determination requires that: Requirements Technical people communicate technical Technical knowledge to people who don’t understand technology technology Business people communicate business Business knowledge to people who don’t understand business business These gaps must be addressed These must Overview of Chapter 5 Process and Outcomes of Requirements Process Determination Determination Traditional methods Modern methods Modern Radical methods Overview of Methods Traditional methods (still used extensively!) Traditional – – – – Modern methods – – Interviewing Questionnaires Observation Analyzing Procedures and other Documents Joint Application Design Prototyping Prototyping Radical methods – – Business Process Reengineering Disruptive Technologies Process and Outcomes of Requirements Determination Determination Document what the person/group does + how Document how processes should be done Document should Document what the system does and will do + how Document the system/data fit in with the processes the Document the data the system needs and the data Document the system creates and stores the Have enough information to be able to draw Have to system process + data models (next stage) system One Hospital’s Insurance Process One Three primary activities Identify potential development projects Classify and rank development projects Select development projects Traditional Methods: Traditional Interviewing Advantages – – – Rich data Followup is possible Involves and engages the user commitment Disadvantages – – – Fairly expensive, especially of your time Information may be subjective (social desirability bias) You know who gave input—not confidential in that way Traditional Methods: Traditional Interviewing Things to Consider: – – – – – – – Thorough preparation—checklist, agenda, questions Take notes or tape record (with permission) Individual or Group interviews Range of people to interview over time—all levels, types Length of interview Open-ended or closed-ended questions Follow-ups to interview (immediate or from writing it up) Success Keys – – – Ask right questions to right people Listen objectively and thoroughly Manage (lower) interviewee expectations Traditional Methods: Traditional Questionnaires Advantages Advantages – – – Efficient use of your time Cost effective Can be made confidential Disadvantages – – – Data is not very rich Hard to followup—can’t if confidential Doesn’t engage user low commitment Traditional Methods: Traditional Questionnaires Things to Consider: – – – – – Who to sample—representative of users Which questions to ask Will it be confidential or not? How long—short is best All closed ended question or some open-ended? Success Keys – – – Never use as a substitute for Interviews Ask right questions to right people Give them a chance to provide open input Traditional Methods: Traditional Direct Observation Advantages Advantages – – – Reality is apparent (informal, not formal system) Unobtrusive to user Very rich data Disadvantages – – Expensive to the user Hawthorne effect Traditional Methods: Traditional Direct Observation Things to Consider: – – – – Who to observe—key roles, people, processes How long—because it can be expensive How to overcome your own biases How to deal with/overcome the Hawthorne effect Success Keys – – – Watch the most important processes Build trust in the person(s) observed Make sure you validate this is really the way it’s done Traditional Methods: Traditional Document Analysis Advantages Advantages – – – Unobtrusive Inexpensive Objective Disadvantages – – – Formal system—may not reflect practice Outdated information? Low user engagement low commitment Traditional Methods: Traditional Document Analysis Things to Consider: – – – – Which Documents and Procedures to analyze What exactly to look for of import How much detail to examine How current Success Keys – – Discerning formal from informal systems Examine with a critical eye, an eye toward improvement Overview of Methods Traditional methods √ Interviewing Interviewing √ Questionnaires Questionnaires √ Observation Observation √ Analyzing Procedures and other Documents Analyzing Modern methods Joint Application Design – Prototyping Prototyping Radical methods – – – Business Process Reengineering Disruptive Technologies Modern Methods: Modern Joint Application Design (JAD) Advantages Advantages – – – – Very rich data More efficient than interviews High involvement commitment Fresh ideas Disadvantages – – Very expensive Hard to control and direct Modern Methods: Modern JAD Things to Consider: – – – – – Who are the key stakeholders to invite Where to hold it Where Facilitation—trained or not Length, number Topic(s) for JAD session Success Keys – – Bring the issues to a consensus (prepare them for this) Make sure people feel they have been heard before the Make before JAD session JAD Modern Methods: Modern Prototyping Prototyping is a subset of Rapid Application Prototyping Development (RAD) Development Identify A Requirement Build a Prototype Review with User Revise Prototype Modern Methods: Modern Prototyping Advantages Advantages – – – High user involvement Very visual, concrete, and realistic Quick, iterative improvements Disadvantages – – – – – Tools may be expensive Lack of formal specs makes it hard to ramp up to full size May be idiosyncratic to the user(s) who reviewed it May become a “stovepipe” system not connected to other May systems systems May neglect standards on some security, controls, etc. Radical Methods: Business Process Radical usiness Reengineering (BPR) Reengineering Definition: “The fundamental reconsideration The and radical redesign of organizational processes, and in order to achieve drastic improvement of current in drastic performance in cost, service and speed.” (Hammer & Champy) (Hammer Example: Ford’s accounts payable had 500 people; Example: Mazda’s had 5. Was BPR needed? …Duh… Mazda’s Radical Methods: Business Process Radical usiness Reengineering (BPR) Reengineering Applying BPR to Requirements: Determine key business processes Analyze them in detail Identify process candidates for radical Identify improvement improvement How? Same as before: interviews, observations, Same documents documents Look for redundancies, excessive inspections, Look rekeying, rework rekeying, Radical Methods: Business Process Radical usiness Reengineering (BPR) Reengineering So how does BPR affect Requirements? 1. Clean slate thinking—to produce the best process 2. Builds radical process improvement into SA&D 3. It focuses on eliminating redundant handling and It rework rework Radical Methods: Disruptive Technologies Disruptive Definition: those techs that enable the breaking of Definition: long-held business rules that inhibit radical change long-held 2. Working with BPR: Apply information technologies in radical ways. 1. Example: Saturn applies EDI technology to link their Example: computers to those of their suppliers—as if it were all one company all Selecting Systems Projects Selecting Imagine you are a business executive – – Your 2008 budget of 50 peoples’ systems work must be Your reduced to 25 reduced How will you make the reductions? With a 1-N list! Rank projects by various criteria – – – Purpose (competitive necessity, revenue generation, cost Purpose reduction) reduction) Magnitude of benefits Strategic potential Recap: Things You Learned Recap: Key system concepts The process of Requirements Determination The The output of Requirements Determination The The Pros and Cons of system Requirements The Determination methods Determination Considerations for each method The complexity involved in system specs How BPR and prototyping affect requirements How development development ESSENTIAL 2 Know Key terms – Explain why requirements Explain determination is so difficult determination – Concepts in Victor-Cooprider model – 3 ways BPR affects requirements – Pros and Cons of requ’s. methods: Pros – interviewing, observation, questionnaire, JAD, prototyping, document analysis prototyping, ...
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This note was uploaded on 11/17/2011 for the course ITM 311 taught by Professor Harrisonmcknight during the Fall '10 term at Michigan State University.

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