Copyright © 2005 Bolton Institute Copyright © 2005 University of Bolton 1 Systems Analysis Investigation Techniques

Copyright © 2005 Bolton Institute Copyright © 2005 University of Bolton 2 Recap DFDs are typically produced in the form of a context diagram, level 1 and level 2 diagram. Context diagram typically shows entities involved in required system. Level 1 diagram typically shows main processes and data stores of system under investigation. Level 2 diagram typically shows detail of processes, including any data stores unique to a process.

Copyright © 2005 Bolton Institute Copyright © 2005 University of Bolton 3 Investigation techniques Why investigate? Need to know how existing system operates. Find out problems / opportunities. Identify ‘new’ services / functions. Initiate involvement with relevant stakeholders.

Copyright © 2005 Bolton Institute Copyright © 2005 University of Bolton 4 Preliminary work Terms of reference Who wants the analysis performed? Any restrictions – time, money, quality issues, H/W, S/W, legacy applications, security, personnel issues? Reporting structures / formats? Background Organisation structure. Current documentation. Previous reports. Surveys / marketing information. Staff availability.

Copyright © 2005 Bolton Institute Copyright © 2005 University of Bolton 5 Planning Data gathering – such as interviews, documentation, system overview, observations, audit trails. To include: Resources – people, equipment, accommodation. Environment – layout, conditions. Method of work – supervised, planned, interrupt. Information flow – purpose, content and suitable samples. Procedures – formal / informal for normal / exceptional. Volumes / frequencies Controls – physical, financial, quality Problems – symptoms and potential causes.

Copyright © 2005 Bolton Institute Copyright © 2005 University of Bolton 6 Information flow Inputs – documents and messages Outputs – reports, letters, messages Storage – data storage, reference Data Flow Diagrams useful for this

Copyright © 2005 Bolton Institute Copyright © 2005 University of Bolton 7 Methods of investigation Observation – not widely used, due to potential resentment and Hawthorne effect. Searching / reviewing current documentation. Sampling – reviewing a small number of a process. Questionnaires Interviews

Copyright © 2005 Bolton Institute Copyright © 2005 University of Bolton 8 Interview Technique Interviews should be planned – participants, date/time, location, sequence, objective, points to cover. Interviews must be arranged with relevant personnel. Introduction – analyst should put people at ease, explain why interview is required and relevant reasons.

Copyright © 2005 Bolton Institute Copyright © 2005 University of Bolton 9 Information gathering Use appropriate language, respect people, present facts not opinions, take notes quickly. Do not criticise! Be aware of: Pace – adjust, as required, listen carefully. Sequence – Try to keep to a pre-planned sequence, avoid being sidetracked. Questions – Avoid leading questions, and too many open questions. Flow – ensure questions are at least attempted. Pause, as and when appropriate.

Copyright © 2005 Bolton Institute Copyright © 2005 University of Bolton 10 Interview conclusion Try to finish when agreed, else interviewee may become annoyed. Summarise interview and request confirmation. Request additional interview, if required. Outline what happens next – possibly provide documented overview, if they request it.

Copyright © 2005 Bolton Institute Copyright © 2005 University of Bolton 11 Interview record After interview, document interview – does not have to be verbatim. Cross-check interview, where possible, with other stakeholders. Maintain documentation within a central project file.

Copyright © 2005 Bolton Institute Copyright © 2005 University of Bolton 12 Recap See handout documentation / examples.