Identifying need and establishing requirements

Identifying need and establishing requirements

1. May aim to replace, update, establish or develope a system

2. 2 Main Aims

   • 1) Understand as much as possible about the users, work, context.
   • 2) Our second aim is to produce from the needs, a set of stable requirements
   • How to achieve them
     • Gather data, then interpret, extract requirements,
       • The process of this activities can interfer in the information that is gathered
       • Unclear objectives and requirements lead to failure
         • If requirements are wrong can cause lose of productivity, griefy, anxiety, stress
       • Recommended to use user centered aproach
       • Data Gathering: Collect sufficient, relevant, appropriate, data so that the set of stable requirements can be produced
         • Questionares, Interviews, Focus Groups, Observation, Studying Documentation
           • The lack of questions, developement, resources will influence the choice of technique, also the time and level of detail
         • 1) Organize your 1st data gathering session
           • 2) Focus on what the stakeholders need
             • 3) Involve the stakeholders
               • 4) Combine gathering techniques
                 • 5) Run a pilot session
                   • 6) Record data in face to face interactions
       • Interpretations: To begin structuring and recording descriptions of requirements
         • More analysis equals deeper understanding

3. The activity of understanding what a product should do

   • Gathering, Capture, Elicitation, Analysis, Engineering
     • Elicitation: implies that others (users) know the requiremets and we have to get them all of us.
       • Analysis: Investigating and analyzing the initial set of requirements,
         • Engineering: Recognizes the developement requirements
           • Software Engineering:
             • 1) Functional requirements which say what the system should do
               • Non- Functional Requirement: Which say what constraints there are on the system and its developement
                 • ARANZA ESTRADA A01176250
                   • Preece, Jennifer. (2002). Interaction Design. United States of America: John Wiley & Sons Inc.
             • Enviromental Requirements: context of use of the interactive product will be expected to operate
               • Physical: lighting, noise, dust
               • Organizational Environment: How good is user support likely to be
               • Social Environment: Will data need to be shared?
               • Technical Environment: What technologies will the product run on?
               • User Requirements: Characteristics intended for the group
                 • Usability Requirements: Capture the usability goals and associated measures for a product
                   • Related to which users are expected to interact with the product
   • Requirement: Is a statement about an intended product that specifies what it should do or how it should perform
     • Should be specific, unambiguous and clear as possible

4. Task Description: Are used throughout developements, from early requirements activities

   • 1) Scenarios: informal narrative description. Describes human activities or task in a story that allows exploration of context, needs, requirements
   • 2) Use Cases: Also focus on user goals but the emphasis is on a user-system interaction rather than the users task itself
   • 3) Essential Use Cases: To combat what they see as the limitations of both scenarios and use cases
     • Instead of actors they are associated with user roles. Also represent abstractions from scenarios

5. Task Analysis: Use to investigate an existing situation not to envision new systems or devices

   • Covers techniques for investigating cognitive process and physical actions at high level of abstraction in minute detail
   • Hierarchical Task Analysis: Design to identify training needs. Tasks into subtasks
     • Graphical Box and Line Notation

Images and files in the map