Data Gathering Techniques

1. Data Gathering Techniques 27th February 2012

2. Data Gathering Techniques • System requirements specify what the system must do or what property or quality the system must have • Need to be able to gather system requirements • Functional Requirements • Non-functional Requirements

3. Functional and Non Functional Requirements • Functional Requirements: System requirements that specify what the system must do are frequently referred to as functional requirements • Non-Functional Requirements: Specify properties or qualities of the system

4. Failure to correctly identify system requirements: • More costly than projected • Delivered later than promised • Fail to meet users expectations • Cost of maintenance may be too high • Unreliable and prone to errors • Negative impact on reputation of IT staff

5. Requirements Discovery • Once the system analyst understands the problems they can successfully define the system requirements • They use fact-finding techniques to collect information about the system problems, requirements and preferences • Fact-finding defines a formal process of using research, meetings, interviews and questionnaires etc.

6. Documenting and Analysing Requirements • Document the draft requirements • Analyse requirements • Identify missing reqs. • Conflicting reqs. • Infeasible reqs. • Overlapping reqs. • Ambiguous reqs. • Formalize requirements • Produce requirements definition document

7. Fact finding Techniques • An analyst usually applies many techniques during a project leveraging advantages of each • Analysts must take great care to ensure they conduct business in an ethical manner

8. Existing Documentation and Forms • Enables the analyst to get a good feel for the existing system • Always gets the facts from existing documentation rather than from people • Employ document and file sampling techniques

9. Research and Site Visits • Site visits with companies who have experienced similar problems

10. Observation of the Work Environment • Analyst either observes or participates in activities to learn about the system • Advantages: • Very reliable • Reduce the complexity of tasks • Inexpensive • Facilitates work measurements • Disadvantages: • People may behave differently • Time period may not convey the complexity of the work • Inconvenient schedule • Task interruptions • Does not allow for analyst to see system exceptions • Work may be contrived due to presence of analyst

11. Questionnaires • Advantages: • Quick • Inexpensive • Maintain anonymity • Rapid analysis • Disadvantages: • Number of respondents • Response rate • Inflexible • No body language • Lack of opportunity for clarification • Difficult to prepare

12. Interviews • Advantages: • Interviewees can actively contribute to the system • Opportunity for further probing • Adapt to interviewee • Observe non-verbal communication • Disadvantages: • Time-consuming • Dependent on analysts interpersonal skills • Impractical

13. Conducting Interviews • Select interviewees • Prepare • Follow up on interview • Listening • Body language

14. Discovery Prototyping • Advantages • Users can experiment with software • Assess the feasibility of system • Acts as training mechanism • Aids to build test plan • Minimise time spent on fact finding • Disadvantages • Training may be required • Users may develop unrealistic expectations • May extend development schedule and cost

15. Joint Requirements Planning • Highly structured group meetings are conducted for the purpose of analysing problems and defining problems • Including: • Sponsor, facilitator, users/managers, scribe, IT staff • Benefits: • Involves users and managers • Reduces system development time • Design approvals based on prototyping

16. Fact Finding Strategy • Systems analyst needs an organised method for collecting fact. • Learn from existing documents • If appropriate observe system in action • Distribute questionnaire • Conduct interviews • Build discovery prototype (optional) • Follow-up –use appropriate fact-finding techniques to verify facts