1. Interfaces for Staying in the Flow Benjamin B. Bederson Computer Science Department Human-Computer Interaction Lab University of Maryland www.cs.umd.edu/hcil bederson@cs.umd.edu

2. Human Goals  Life Goal: Happiness  Work Goal: productivity, creativity, recognition, etc.

3. Flow – Folk Definition  “To move or run freely in the manner characteristic of a fluid”  Concentrate to the exclusion of all else  To be “in the zone”  Counter example: Writer w/ writer’s block

4. Flow – Psychology Definition  “Optimal Experience” – see “Flow” by Mihaly Csikszentmihalyi (1990)  Started by interviewing “experts”  Then used “Experience Sampling Method” => Characteristics of optimal experience => Flow is universal, and is a combination of activity, individual and state of mind

5. 1. Challenge and Require Skill  Person must expend effort to acquire skills, and then apply them  Examples: Tennis Programming  Not passive or relaxing  Not “go with the flow”

6. 2. Concentrate  Ability to focus attention at length is crucial  Focusing enables tuning out of other input  People w/ A.D.D. at real disadvantage  Examples: Reading Painting

7. 3. Clear Goals and Feedback  Must define success up front  Clearly measure progress along path  Examples: Surgery Factory work

8. 4. Maintain Control  Minimize loss of “objective” control  Maximize “subjective” control  Examples: Mountain climbing Counter example: Driving in traffic

9. 5. Transformation of Time  Time flies  Or, can slow down  Examples: Pottery New romantic interest

10. Our Goal  Build computer systems that work as a “tool” to support optimal experience ► But computers could never be that good. You’ve described only simple tools. ► But isn’t flow a fuzzy, unmeasurable and unscientific concept? And even if you could measure it, is it really important?

11. Interfaces for Staying in the Flow  How do these characteristics of flow apply to interface design?

12. 1. Challenge and Require Skill  Interfaces should be: neither so difficult as to discourage users nor so easy as to be boring Demo TimeSearcher Challenges Skills Flow Channel Boredom Anxiety

13. 2. Concentrate  Avoid interruptions  Stay in task domain, not interface domain Guimbretière et al. “FlowMenus: Combining Command, Text Entry and direct manipulation” UIST 2000 Three levels of interaction: 1. Learn from the interface 2. Feedback from the interface 3. Autonomous interaction (no feedback necessary)

14. 2. Concentrate (cont.)  Maintain object constancy Save short-term memory Demo PhotoMesa

15. 3. Clear Goals and Feedback  Help user to specify what they are doing  And how they are getting there  Many e-commerce websites

16. 4. Maintain Control  Challenge of “Expert” vs. “Novice” interfaces (controls vs. wizards) (Microsoft vs. Apple philosophy)  Emacs vs. IDEs (Visual Studio & Eclipse) Difficulty of learning Keyboard vs. mouse control Home keys vs. arrow/nav keys Integrated shell, grep, directory, etc. Filename completion, command history

17. 4. Maintain Control (cont.)  Problem w/ adaptive interfaces: Unpredictable Loss of objective control Leads to frustration and slow performance  Encourage controllable, configurable interfaces Demo Favorite Folders

18. 5. Transformation of Time  Based on pyschology principle: When interrupted, people will overestimate time  Relative Subjective Duration (RSD) Czerwinski et al., “Subjective Duration Assessment: A New Metric for HCI”, HCI 2001 Avoids positive bias of subjective preference Demo DateLens

19. Summary  Maintain lofty goals “Computer as tool” should be an extension of our body  Don’t underestimate the importance of speed in supporting: creativity quality enjoyment

20. Design Principles  Human memory is limited  Modes are bad  Input device switches are bad  Maintain object constancy  Minimize use of interface  Balance features vs. ease-of-use

21. Challenge  Design for novices and experts is really hard, but important  Don’t forget the expert!

22. Suggestion  Add Relative Subjective Duration (RSD) to standard list of metrics => Minimizing cognitive load and improving subjective satisfaction can help achieve optimal experience