Page ‹#›Information Systems Analysis and Design csc340Information Acquisition -- 12002 Jaelson Castro and John MylopoulosVII. Information AcquisitionVII. Information AcquisitionWhat is Information Acquisition?What is Information Acquisition?Sampling and Investigating Hard DataSampling and Investigating Hard DataStakeholders and InterviewingStakeholders and InterviewingTypes of Information AcquisitionTypes of Information AcquisitionSampling Hard Data and Using QuestionnairesSampling Hard Data and Using QuestionnairesObservingObserving Behaviour Behaviour and Interpersonal skills and Interpersonal skillsJoint Application Development (JAD)Joint Application Development (JAD)Social Methods and Social IssuesSocial Methods and Social IssuesInformation Systems Analysis and Design csc340Information Acquisition -- 22002 Jaelson Castro and John MylopoulosInformation AcquisitionInformation Acquisition “Information acquisition” refers to the task of capturing all sorts ofrelevant information about how things are currently done, including: Information flow Business processes Data that is used in these processes External and internal data Exception handling Problems with current situation, including existing systems Desirable and undesirable scenaria This is one of the most crucial, and hardest, tasks in the developmentof a software system.Ignorance hidingIgnorance hiding: One of the basic traits of a good systems analystis the ability to hide her ignorance, or more precisely, to find her wayaround in a new problem area quickly.Information Systems Analysis and Design csc340Information Acquisition -- 32002 Jaelson Castro and John MylopoulosInformation AcquisitionInformation Acquisition The term ““Information AcquisitionInformation Acquisition”” should not suggest that theinformation needed by the analyst is explicitly available somewhere(document, someone’s head,...) and all the analyst has to do is findthe source and fetch it (by reading or asking)This is often wrongThis is often wrong The information needed may have to be extracted through analysis,interpretation and synthesis from a variety of sources For example, consider a loan approval department where the analystwants to find out the rule(s) for loan approval; these may not existanywhere (in company documents or people’s heads) and may evenhave contradictory manifestations within the same department The say-dosay-do problem: people know how to do many things theynormally don’t describe (tacit knowledgetacit knowledge); descriptions of such thingsmay be highly inaccurateInformation Systems Analysis and Design csc340Information Acquisition -- 42002 Jaelson Castro and John MylopoulosSubject WorldSubject WorldUsage WorldUsage WorldSystem WorldSystem WorldDevelopment WorldDevelopment Worldmaintains information aboutneedsinformation aboutusesbuildscontractsWhat Information to Acquire?What Information to Acquire?Information Systems Analysis and Design csc340Information Acquisition -- 52002 Jaelson Castro and John MylopoulosThe Four WorldsThe Four WorldsSubject WorldSubject World -- describes the subject matter of the informationsystem; e.g., customers, accounts, transactions for a bankinformation systemUsage WorldUsage World -- describes the environment within which the plannedsystem will operate; e.g., agents who play a role in the usage world,such as managers, clerks, customers; also business processes suchas handling a withdrawal, a deposit of foreign currency,...System WorldSystem World -- describes what the system does within itsoperational environment, what information it contains and whatfunctions it performs; e.g., system records all transactions in adatabase, reports on transactions for a particular account, givesaccount balance,...Development WorldDevelopment World -- describes the development process, team,schedule, required qualities (security, performance,…) etc.; e.g.,system must be delivered within 12 months, level 3 softwareprocesses to be used during its development, must handle up to 1000transactions per second,...Information Systems Analysis and Design csc340Information Acquisition -- 62002 Jaelson Castro and John MylopoulosScenariaScenaria One useful form of information to gather involves desirable orundesirable sequences of events. For example, for a hospital admission system, you may ask: “Suppose I’m admitted into the hospital; what happens during myadmission?” The answer may be like“You, or the person accompanying you, talk to the person at theadmissions desk; you have to show your OHIP card and explainwho referred you to the hospital; then…” Some scenaria describe undesirable sequences of events, such as“You won’t be admitted if you don’t produce your OHIP card”. Out of scenaria, one can build the general business processes usedby the organization being studied, also use cases for the system-to-be.Page ‹#›Information Systems Analysis and Design csc340Information Acquisition -- 72002 Jaelson Castro and John MylopoulosStakeholders (Actors)Stakeholders (Actors)Who are the people who must be consulted during informationacquisition? These are the stakeholdersstakeholders, all those who have a say ofsome sort on the new system. Stakeholders include:Users - who are concerned about the features and thefunctionality of thr new systemDesigners - who want to build a perfect system, or reuse existingcodeSystems analysts - who want to “get the requirements right” Training and user support staff - who want to make sure the newsystem is usable and managableBusiness analysts - want to make sure “we are doing better thanthe competition”Technical authors - who will prepare user manuals and otherdocumentation for the new systemThe project manager - who wants to complete the project ontime, within budget, and with all objectives met.Information Systems Analysis and Design csc340Information Acquisition -- 82002 Jaelson Castro and John MylopoulosInformation Acquisition TechniquesInformation Acquisition TechniquesSampling hard data -- forms, applications,... Background reading -- reports, memos, etc.Interviewing --
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