Entity-Relation-Based Techniques for Task Analysis: Understanding Objects, Actions, and Relationships

1. CMPUT 301: Lecture 16Task Analysis II Lecturer: Martin Jagersand Department of Computing Science University of Alberta Notes based on previous courses by Ken Wong, Eleni Stroulia Zach Dodds, Martin Jagersand

2. Overview: • Last time: • Hierarchical analysis • Temporal plans • Knowledge based analysis • Today: • Entity-relation based analysis • Using several of the above together

3. Entity-Relation-Based Techniques • Understanding objects and actions: • list all objects involved • focus on the relationships between objects and actions, rather than similarities • link actions with objects which help perform them • “object-based”

4. Entity-Relation-Based Techniques • Objects of gardening firm: • tool shed with spade, garden fork, hoe • Ferguson tractor, with plow and harrow • owner (Vera) • two employees (Sam and Tony) • two growing fields • large glasshouse with humidity sensor • computer-controlled irrigation system The kit team

5. Entity-Relation-Based Techniques • Classify objects into three types: • simple objects • “things” • e.g., spade, plow, glasshouse • actors • humans and non-humans that do things • e.g., Vera, Sam, Tony, Fergie, computer • composite objects • objects which consist of other objects • e.g., team, men, kit

6. Entity-Relation-Based Techniques • Look at some attributes of objects: • Object Pump3 simple — irrigation pump • Attributes • status: on/off/faulty • capacity: 100 litres/minute

7. Entity-Relation-Based Techniques • Only enough detail about attributes to describe their use in tasks: • Actions are e.g., • turning on and off irrigation pumps, done by user actor • may not need pump capacity • only needed by repairman for replacement • We can drop unwanted details later.

8. Entity-Relation-Based Techniques • Look at actions that change the state of something: • agent (often an actor), action, patient • associated attributes • e.g., • Sam planted carrots • gardener dug soil with spade • irrigation controller turning on water

9. Entity-Relation-Based Techniques • Message actions: • communication • perhaps in prelude to another action • e.g., • Vera telling Sam to dig the carrots

10. Entity-Relation-Based Techniques • Identify roles: • actors fill in specific roles • an actor can have multiple roles • a role can have multiple actors • e.g., • Vera as worker • Vera as manager • Sam as worker

11. Entity-Relation-Based Techniques • Object Sam human actor • Actions • s1: drive tractor • s2: dig the carrots • Object Vera human actor • Actions as worker • v1: plant seed • v2: program irrigation controller • Actions as manager • v3: tell Sam to dig the carrots

12. Entity-Relation-Based Techniques • Object the men composite • Comprises • {Sam, Tony} • Object glasshouse simple • Attribute • humidity: 0–100%

13. Entity-Relation-Based Techniques • Object Irrigation Controller non-human actor • Actions • ic1: turn on Pump1 • ic2: turn on Pump2 • ic3: turn on Pump3

14. Entity-Relation-Based Techniques • Identify events: • things that happen • Different types e.g., • germination of “seed”(spontaneous action of seed, non-actor) • humidity drops below 25%(no associated object) • at midnight(timed)

15. Entity-Relation-Based Techniques • Identify relationships between objects, actions, and events: • object to object • e.g., Sam is subordinate to Vera • action to object • e.g., (Sam) digs the carrots

16. Entity-Relation-Based Techniques • Relations object–object • located in: ( Pump3, glasshouse ) • located in: ( Pump1, Field1 )

17. Entity-Relation-Based Techniques • Relations action–object • patient ( v3, Sam ) • i.e., Vera tells Sam to dig • patient ( s2, the carrots ) • i.e., Sam digs the carrots • instrument ( s2, spade ) • i.e., Sam digs the carrots with the spade

18. Entity-Relation-Based Techniques • Relations action–event • before ( v1, m1 ) • i.e., seed must be sown before it can germinate • triggers ( ev1, ic3 ) • i.e., when humidity drops below 25%, the controller turns on pump 3 • causes ( v2, ic1 ) • i.e., the controller turns on pump 1 because Vera programmed it • etc.

19. Combining Approaches • 0 To grow carrots • 1 Vera sows the seed • 2 seed germinates • 3 Vera programs controller • 4 controller waters field • 5 carrots grow • 6 Sam hoes • 7 Tony harvests carrots

20. Combining Approaches • Plans: • plan 0 • do 1, 2, 5, when crop is mature do 7 • when rainfall is low, do 3, 4 • when weeds grow, do 6

21. Combining Approaches Combining Approaches • Look at a particular object and all the actions in which it participates: • life cycle diagram • many tasks

22. Combining Approaches

23. Combining Approaches • Use knowledge-based (taxonomic) analysis: • identify commonalities of actions and relations • build inheritance hierarchy • “object-oriented” • e.g., Sam and Tony could do some things in common

24. Sources of Information • Need to collect information about tasks from various sources: • documentation • observation • initial analysis • sorting and classification

25. Sources of Task Information • Documentation: • e.g., existing manuals, training materials, job descriptions • job descriptions may only describe what people are supposed to do, not what they actually do • equipment manuals may only describe functions or features, not tasks

26. Sources of Task Information • Observation: • formal or informal • in the field on in the lab • passive or active • note taking • video taping • talk aloud • walkthroughs • confirm task analyses

27. Sources of Task Information • Interviews: • pose questions to domain experts directly • follow up on responses with more questions, for more detail

28. Sources of Task Information • Initial analysis: • following on from manuals, observation, or interviews • build lists of objects (nouns) and actions (verbs)

29. Sources of Task Information • Sorting and classification: • use note cards of task objects • have a domain expert sort cards into piles by similarity • use spatial arrangement • compare groupings among experts • use an outliner

30. Uses of Task Analysis • Manuals: • use hierarchical task analysis to structure training materials(“how to do it”) • use knowledge-based techniques to structure a course or textbook(concepts and foundations)

31. Uses of Task Analysis • Requirements capture: • task analysis of existing procedures • help in eliciting what the new system must do and guiding its design • how the system is used versus what the system does • compare new and old procedures

32. Uses of Task Analysis • Detailed interface design: • use task decomposition trees to design menus and layout dialogs • or use roles and tasks within each role to design menus • or use objects and what can be done to it to design menus • use taxonomies for grouping • avoid too much “movement”

33. End • What did I learn today? • What questions do I still have?