Information Systems Analysis and Design csc340 Information Systems Analysis and Design csc340 VII Information Acquisition Information Acquisition What is Information Acquisition Sampling and Investigating Hard Data Stakeholders and Interviewing Types of Information Acquisition Sampling Hard Data and Using Questionnaires Observing Behaviour and Interpersonal skills Joint Application Development JAD Social Methods and Social Issues Information acquisition refers to the task of capturing all sorts of relevant 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 development of a software system Ignorance hiding hiding One of the basic traits of a good systems analyst is the ability to hide her ignorance or more precisely to find her way around in a new problem area quickly 2002 Jaelson Castro and John Mylopoulos Information Systems Analysis and Design Information Acquisition 1 csc340 2002 Jaelson Castro and John Mylopoulos Information Systems Analysis and Design The term Information Acquisition Acquisition should not suggest that the information needed by the analyst is explicitly available somewhere document someone s head and all the analyst has to do is find the source and fetch it by reading or asking This 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 analyst wants to find out the rule s for loan approval these may not exist anywhere in company documents or people s heads and may even have contradictory manifestations within the same department The say do problem people know how to do many things they normally don t describe tacit tacit knowledge knowledge descriptions of such things may be highly inaccurate Information Systems Analysis and Design Information Acquisition 3 csc340 needs information about Subject World maintains information about uses builds System World contracts Usage World Development World 2002 Jaelson Castro and John Mylopoulos Information Acquisition 4 Information Systems Analysis and Design The Four Worlds csc340 Scenaria Subject World describes the subject matter of the information system e g customers accounts transactions for a bank information system Usage World describes the environment within which the planned system will operate e g agents who play a role in the usage world such as managers clerks customers also business processes such as handling a withdrawal a deposit of foreign currency System World describes what the system does within its operational environment what information it contains and what functions it performs e g system records all transactions in a database reports on transactions for a particular account gives account balance Development World describes the development process team schedule required qualities security performance etc e g system must be delivered within 12 months level 3 software processes to be used during its development must handle up to 1000 transactions per second 2002 Jaelson Castro and John Mylopoulos csc340 What Information to Acquire Information Acquisition 2002 Jaelson Castro and John Mylopoulos Information Acquisition 2 Information Acquisition 5 One useful form of information to gather involves desirable or undesirable sequences of events For example for a hospital admission system you may ask Suppose I m admitted into the hospital what happens during my admission The answer may be like You or the person accompanying you talk to the person at the admissions desk you have to show your OHIP card and explain who 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 used by the organization being studied also use cases for the system tobe 2002 Jaelson Castro and John Mylopoulos Page Information Acquisition 6 Information Systems Analysis and Design csc340 Information Systems Analysis and Design Stakeholders Actors Information Acquisition Techniques Who are the people who must be consulted during information acquisition These are the stakeholders all those who have a say of some sort on the new system Stakeholders include Users who are concerned about the features and the functionality of thr new system Designers who want to build a perfect system or reuse existing code Systems analysts who want to get the requirements right Training and user support staff who want to make sure the new system is usable and managable Business analysts want to make sure we are doing better than the competition Technical authors who will prepare user manuals and other documentation for the new system The project manager who wants to complete the project on time within budget and with all objectives met 2002 Jaelson Castro and John Mylopoulos Information Acquisition 7 Information Systems Analysis and Design csc340 Sampling hard data forms applications Background reading reports memos etc Interviewing meeting with people and asking questions Questionnaires distribute a questionnaire to relevant people collect their responses and analyze them Observation spending some time observing the organizational setting where the new system will be deployed 2002 Jaelson Castro and John Mylopoulos Mr Ms Mrs Miss Dr Name Address City Prov Postal Code Phone No H B I am interested in Data capture forms are very important Collect them study them before changing them Information Systems Analysis and Design csc340 Hard Data An Example Facts and figures financial information organizational contexts document types problems Reports used for decision making such as status of inventory sales production Performance reports usually take the form of actual vs expected second derivatives are important if there is a gap is it widening or narrowing Records keep track of what s happening important to keep them up to date 2002 Jaelson Castro and John Mylopoulos Information Acquisition 8 Information Systems Analysis and Design Hard Data csc340 receiving United Way Newsletter receiving information on United Way community fund including United Way in my will Information Acquisition 9 csc340
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