1. CARE properties Chris Vandervelpen chris.vandervelpen@uhasselt.be

2. Overview Introduction CARE properties explained S-CARE properties v.s. U-CARE properties CARE integration –Design –Deployment Conclusions Questions

3. Introduction [Nigay, Coutaz 1995: Multifeature systems: The CARE properties and their Impact on Software Design] Interaction Technique = Modality = Physical Device + Interaction Language: –Direct Manipulation Input: Mouse / Direct manipulation language –Direct Manipulation Input: Touchscreen + Stylus / Direct manipulation language –Speech Input: Microphone / Pseudo natural language –Speech output: Speaker / Natural language –Audio output: Speaker / Set of sounds –Graphical output: Screen / graphical Language

4. Introduction CARE properties –Evaluating usability Interaction flexibility System robustness –Relations between interaction techniques and tasks Classification of and reasoning about interactive multi modal systems

5. CARE explained System CARE properties  Relations –C omplementarity –A ssignment –Redundancy –E quivalence CARE relations are –Permanent or transient: states –Total or partial: tasks

6. CARE Explained: Equivalence Equivalence(I,s,T) -Interaction techniques in a set I are equivalent over a state s and a set T of tasks if all of the tasks in T can be performed using either one of the interaction techniques in I Total (tasks) / Permanent (states) Filling in departure city in a form –Speech: say “Brussels” –Direct Manipulation: Choose “Brussels” from a drop-down list using the mouse

7. CARE Explained: Assignment Assignment(i,s,T) -An interaction technique i is assigned to a set of tasks T in a state s if there is no other interaction technique that is equivalent to it for a set of tasks T in state s Total (tasks) / Permanent (states) 3D navigation –Very difficult using speech –Assign direct manipulation with mouse interaction technique to this task

8. CARE Explained: Redundancy Redundancy(I,s,t) –Interaction techniques in a set I can be used redundantly for performing a task t in state s if they can be used simultaneous to execute task t in state s Total (tasks) / Permanent (states) Selecting toppings for the pizza using speech and DM redundantly -Speech: “I want pizza with onion” -Direct Manipulation: “Selecting onion from a list” using the mouse -Use the two simultaneous

9. CARE Explained: Complementarity Complementarity(I,s,T) –Interaction techniques in a set I are complementary in a state s for tasks in a set T if T can be partitioned in subsets Tp and there exists an interaction technique in I that is assigned to Tp –Say “I want a flight from this city to that city” (speech) while selecting Brussels and Amsterdam from a list using a mouse (direct manipulation) Speech denotes the slots (this and that) Direct manipulation denotes the slot values (Brussels and Amsterdam)

10. CARE Explained: Usability assessment Equivalence –Enhance flexibility Multiple choices –Enhance robustness Noisy: speech not adequate  DM Silent: use speech Redundancy –Enhance robustness One modality is a backup for the other Complementarity –Danger of cognitive overload –Implementation: synchronization problems UI Consistency –Partialness (tasks) –Transiency (states)

11. CARE Explained: Usability assessment System CARE v.s. User CARE U-CARE properties –User’s choice between modalities –Translated to user preferences –Compatibility with S-CARE properties

12. CARE Integration Research challenges –Extend model-based user interface design (MBUID) with multi-modal user interfaces capability Integrate/relate the CARE properties into existing MBUID models (environment model, task model, user model) –Deploy multi-modal user interfaces in an AmI environment using MBUID Using the updated models to dynamically deploy the UI Make decisions for distributing UI keeping CARE properties in mind

13. CARE integration: Environment model Interaction cluster  Interactive device For all interaction clusters in environment model  define supported interaction techniques For example –desktop_computer001 cluster supports it1: dm/mouse it2: speech_input/microphone it3: speech_output/speaker it4: graphic_output/screen

14. CARE Integration: Task Model Specify for every task the suitable interaction techniques and the CARE properties between them Make task associations explicit in ConcurTaskTree

15. CARE Integration: Task Model multimodal tasks unimodal tasks R(it1,it2) E(it1,it2) R(it3,it4) A(it1) it1: dm/mouse it2: speech_input/microphone it3: speech_output/speaker it4: graphic_output/screen

16. CARE Integration: User model Users define interaction technique preferences  U-CARE –Globally –For particular tasks –In particular circumstances (context dependent) If noisy environment, prefer DM otherwise prefer speech When in car, prefer speech otherwise prefer DM If in meeting, use DM, otherwise use speech

17. CARE Integration: Deployment Using information in updated models to –Help UI designer make decisions based on environment possibilities –Choose modality and/or deployment device (interaction cluster) at runtime

18. Conclusions CARE properties –Make reasoning about multimodal user interfaces possible –Useful for designing/deploying multimodal user interfaces in a MBUID process –Useful for assessing the usability of a system Further research needed

19. Questions???