Mobility as a challenge for interaction design<br />Antti Oulasvirta<br />with many others<br />Helsinki Institute for Inf...
Who? Antti Oulasvirta<br />SICSA DVF<br />Senior researcher, HIIT 2008-2011<br />Postdoc, UC Berkeley 2007-2008 <br />PhD,...
Disclaimer<br />	This presentation was held for the SICSA Summer School on Multimodal Interaction and Digital Tourism in S...
Contents<br />Walking and locomotion<br />Attention<br />Multitasking<br />Manual resources<br />Information foraging<br /...
INTRODUCTIONWhat is mobility?<br />What does it mean for something to be mobile?<br />
            ”Static” <br />”Mobile”<br />Confined area<br />Unrestricted area<br />Mostly instrumented environment<br />Mo...
First academic studies<br />Kristoffersen & Ljungberg (1999). Making place to make “IT” work.<br />Pascoe et al. (2000). U...
Understanding Mobile Contexts, Presented for Mobile HCI 2003 by Antti Oulasvirta<br />I Situational Acts Within Planned On...
Understanding Mobile Contexts, Presented for Mobile HCI 2003 by Antti Oulasvirta<br />IIa Claiming Personal Space<br />The...
Understanding Mobile Contexts, Presented for Mobile HCI 2003 by Antti Oulasvirta<br />IV Temporal Tensions<br />Users must...
Understanding Mobile Contexts, Presented for Mobile HCI 2003 by Antti Oulasvirta<br />IVa Hurrying <br />Physical and soci...
 Selecting the shortest route
 Anticipating changes in the environment</li></ul>+ Informing related persons for being late<br />Multitasking cognitively...
Understanding Mobile Contexts, Presented for Mobile HCI 2003 by Antti Oulasvirta<br />IVb Waiting<br />End signal must be ...
Understanding Mobile Contexts, Presented for Mobile HCI 2003 by Antti Oulasvirta<br />V Multitasking<br />Navigation requi...
Dynamic<br />Reactive<br />Embodiment<br />Human-Computer-EnvironmentInteraction<br />Movement<br />
Societal<br />Social<br />Experienced<br />Cognitive<br />Behavioral<br />Biological<br />Physical<br />Dynamic<br />React...
Design challenge<br />Ensure information has its intended effect at the right moment<br />Maximize users’ ability to use i...
1. Walking vs. Interaction<br />
“Human walking is a risky business. Without split-second timing man would fall flat on his face; in fact with each step he...
The multiplex of human mobility<br />Prof. Colwyn Trevarthen<br />
Mutual distraction<br />What is the effect of a mobile device?<br />Distracts head control<br />Distracts use of hands<br ...
Studies<br />	From standing/sitting to WALKING<br />1923s text entry completion time [1]<br />1813wpm w/ multimodal UI (...
Reading<br />Study by Mustonen et al. (2004)<br />
What happens to target acquisition?<br />
Preferred Walking Speed<br />longer<br />step<br />shorter<br />step<br />Cavanagh & Williams (1982)<br />
Walking<br />Bergstrom-Lehtovirta, Oulasvirta, & Brewster (2011) Proc. Mobile HCI’11<br />Bergström-Lehtovirta, Oulasvirta...
Design implications<br />ALWAYS A COST for mobile interaction <br />About 60-80% of preferred walking speed is the “optima...
2. Attention<br />Visual occlusion<br />Multimodal flexibility<br />Multitasking<br />Inattentional blindness<br />
Neural systems of 3D spatial control<br />2m- distant<br />Upper 360°<br />0.2m- distant<br />Central 20-30°<br />Navigati...
The visual occlusion technique<br />Senders 1967<br />
Visual sampling (video) <br />From Oulasvirta et al. (2005) Proc. CHI’05<br />
Blindfolding world’s best texter<br />From Oulasvirta & Bergstrom-Lehtovirta (2010) Proc. CHI2010<br />LG Texting World Ch...
Blocking methodology<br />
Multimodal Flexibility<br />Ear protection<br />Cardboard<br />Plastic layer<br />Oulasvirta & Bergström-Lehtovirta 2010<b...
Bimodality indices<br />From Oulasvirta & Bergstrom-Lehtovirta (2010) Proc. CHI2010<br />
3. Multitasking<br />
Attention and multitasking<br />The resource pool theory of Navon<br />
The Multiple Resources Theory of C.D. Wickens<br />
Argumentation Outline<br />Mobile situation<br />A number of tasks to manage<br />Cognitive resource competition<br />Frag...
Reitti<br />
	                   The Fragmented Nature of Attention in Mobile HCI    46<br />Hypothesis<br />We’ll be looking at mobile...
Fragmentation of attention<br />Oulasvirta et al. (2005) Proc. CHI’05<br />Oulasvirta, Roto, Tamminen, & Kuorelahti 2005<b...
	                   The Fragmented Nature of Attention in Mobile HCI    48<br />Output video, data<br />Oulasvirta et al. ...
Coding<br />1. LocationOne of the nine exp. places<br />2. User input Starts / stops commanding<br />6. Visual gazePhone /...
Oulasvirta et al. (2005) Proc. CHI’05<br />
Oulasvirta et al. (2005) Proc. CHI’05<br />
	                   The Fragmented Nature of Attention in Mobile HCI    52<br />Crowdedness (r=.25)<br />Oulasvirta et al....
Patterns of time-sharing<br />Oulasvirta et al. (2005) Proc. CHI’05<br />
Inattentional blindness<br />
The unicycling clown experiment<br />
Design challenge<br />How complex is the environment?<br />Can the critical information be extracted in 0.5-1.5 s?<br />Is...
4. Manual resources<br />
Working 3.5h<br />Leisure and free time 5.3h<br />Purchasing goods 0.8h<br />Eating and drinking 1.2h<br />Educational act...
Human hand model<br />
Manual Multitasking Test<br />A test battery with 12 tasks, derived from<br />Statistics of time use<br />A human hand mov...
Comparing 3 input interfaces<br />Stylus<br />Touchscreen<br />QWERTY<br />Oulasvirta & Bergstrom-Lehtovirta (2011) Proc. ...
Design implications<br />Which objects are your users carrying and manipulating?<br />Which form factor would distract the...
5. Information Foraging<br />
Peter Pirolli<br />
The optimal foraging strategy?<br />“An animal will forage so long as the expected rate of gain within a patch is greater ...
Information<br />Energy<br /><ul><li>Prey vary by profitability.
Environment may be patchy.</li></ul>Energy = information<br />From Peter Pirolli’s slideset available in the internet<br />
“If time / distance between patches is reduced, optimal time in any one patch is shorter”<br />tba<br />tbb<br />From Pete...
“If patch abundance is increased, optimal time in any one patch is reduced”<br />tb<br />More information faster equals lo...
Cognitive model<br />new<br />cell<br />Information<br />Goal<br />medical<br />patient<br />Link Text<br />treatments<br ...
Temporal scales<br />Newell<br />Psychological<br />domain<br />Time scale <br />(s)<br />107<br />106<br />105<br /><ul><...
Task</li></ul>101<br />100<br />10-1<br /><ul><li>Unit task
Operations
Visual attention
COGNITIVE(Proximal Mechanisms)</li></ul>From Peter Pirolli’s slideset available in the internet<br />
When should I change the patch?<br />Cumulative gain<br />g(tW)<br />R*<br />R2<br />R1<br />t1<br />t*<br />t2<br />tB<br...
Charnov’s marginal value theorem<br />“Max gain when slope of within-path gain g = average gain R (tangent in diagram)”<br...
Information scent<br />Tokyo<br />“Cues that facilitate orientation, navigation, assessment of information value”<br />New...
Example: File system<br />9<br />8<br />Hyperbolic Browser<br />7<br />Slope = 1.09 levels/sec<br />6<br />          = 0.9...
Spreading activation in associative networks<br />~ 200 X 200 million sparse “word” matrix<br />Document<br />corpus<br />...
Spreading activation<br />Activation of node i<br />Ai = Bi + WjSji<br />Base-level<br />activation<br />Activation sprea...
Design challenge<br />How does the structure of and cues in the environment support the user finding targets?<br />How wel...
6. “Embodied interaction”<br />
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Mobility as a challenge for interaction design. Lecture by Antti Oulasvirta

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SICSA Summer School on Multimodal Interaction and Digital Tourism. In St. Andrews, June 2011.

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  • Limited timeLimited physical surfacesLimited handsLimited attention-&gt; Reading email on mobile device only after work, was so effortful-&gt; design ideas for eyes-free and single-hand interactions
  • Locomotion: The ability to move from one place to another- skeletal system, 3 types of muscles, 5 types of joints, connecting tissues Simultaneous control of multiple “behavioral fields”Gait Posture
  • NOT a single study where no effect reportedObstacle course
  • VR: reading velocityVS: search velocity
  • also have to select the target! -&gt; greater cost
  • “Quasi-mobile phones”- Most use of non-communication features takes place when stationary – sitting, standing still, laying down, …
  • With 5.1 letters per word
  • MFI shows that performance decreases…The method is lightweight, it takes only about one hour to run and you can use it in the lab to evaluate practically anything
  • Epähuomiosokeus: “Kävelevätkö mies ja nainen suojatiellä?”  jää näkemättä mies taustalla Muutossokeus: sakkadin aikana tai väläyksen aikana tekstit voivat muuttua
  • - To begin with, The issue is timely. - ATUS [1] reports that waking hours are spent as follows: 5.3 hours per day in leisure and free time, 3.5 h working, 1.8 h in household activities, 1.2 h eating and drinking, 0.8 h purchasing goods and services, 0.5 h taking care of members of the household, and 0.5 h in educational activities.It is hard to think of an activity that doesn’t involve physical objects. Other than sleeping.erilaisiaesineitäliittyyjokaiseenaktiviteettiinlukematonmäärä JA ne kilpailevatkäyttäjänresursseistavuorovaikuttaamobiililaitteenkanssa. - if the UI performs well multi-object manual tasks, it would be more usable in different mobile contexts AND it would be more frequently used!
  • Yleiskuvaus (handedness, anatomically..., reservation of hand).We developed a test battery of manual tasks to address the manual constraints: an additional requiremenst(e.g., holding or manipulating a physical object) and restrictions to regular performance (e.g., the pre- ferred hand cannot be used):- use with the non-preferred hand- reservation of a whole hand for something else - reservation of various parts of a hand - application of force in two directions simultaneouslyfixation of finger position fixation of index-finger-to-thumb distance restricted movement of the shoulder, elbow, and wrist protrusion of an object into the work area of a deviceTälläkalvollapointti on vakuuttaakuulijasiitä, ettätämävirittääavaruudenerilaisistaanatomisistavaatimuksista (constraints)- THE BATTERY: At the core of the MMT are 12 conditions that emulate de- mands arising frequently in the real world. The tasks are described in Table 2, with the associated instructions to subjects.In the test, handedness is studied in Dominant-Only and Non-Dominant-Only conditions, where only one hand or the other may be used. No-Support, where the device is placed on a level surface, addresses the importance of allo- cating a hand to support the device.Anatomically, the test covers not only hand constraints but also restrictions to movement of upper limbs: the shoulder (Big-Object) and the wrist (CoffeeMug). Most of the conditions involve static motion (holding an object), with the exception of Push-Rail and Pull-Rail, which re- quire isometric motion. They were included because direc- tional application of force is common (opening doors, car- rying a bag, holding somebody’s hand, etc.). The two vari- ants were included because different parts of the hand are needed to produce force and to balance the bar: the proxi- mal part of the palm and distal parts of the fingers, respec- tively. Push-Button also requires use of force but reserves only the index finger.The rest of the tasks address ways in which the hand is re- served. Tongs reserves the “pinch” posture (opposition of index finger and thumb), which is important in tasks requir- ing tactual accuracy. Scissors reserves two fingers, the thumb, and optionally another finger, but it requires keep- ing their distance constant, which further restricts the de- gree of freedom in controlling the rest of the palm. The ob- jects in Medium-Object, Scissors, and CoffeeMug are large enough to actually protrude into the work area of an interface held in the hand. 
  • 20-40% decrease due to manual multitasking
  • Mobility as a challenge for interaction design. Lecture by Antti Oulasvirta

    1. 1. Mobility as a challenge for interaction design<br />Antti Oulasvirta<br />with many others<br />Helsinki Institute for Information Technology HIIT<br />Aalto University, Finland<br />
    2. 2. Who? Antti Oulasvirta<br />SICSA DVF<br />Senior researcher, HIIT 2008-2011<br />Postdoc, UC Berkeley 2007-2008 <br />PhD, U Helsinki 2006<br />Area: Mobile HCI<br />www.hiit.fi/u/oulasvir<br />
    3. 3. Disclaimer<br /> This presentation was held for the SICSA Summer School on Multimodal Interaction and Digital Tourism in St. Andrews, Scotland, 2011.<br /> Slides are not “stand-alone”, you may have to check the papers / ask for explanations. <br />
    4. 4. Contents<br />Walking and locomotion<br />Attention<br />Multitasking<br />Manual resources<br />Information foraging<br />Embodied interaction<br />
    5. 5. INTRODUCTIONWhat is mobility?<br />What does it mean for something to be mobile?<br />
    6. 6. ”Static” <br />”Mobile”<br />Confined area<br />Unrestricted area<br />Mostly instrumented environment<br />Mostly uninstrumented environment<br />Many identifiable users<br />Many unidentifiable users<br />Loosely defined tasks<br />Well-defined tasks<br />Few tasks (<20)<br />Many tasks (>10?)<br />Interruptions disrupting<br />Interruptions also positive<br />Leisure time oriented goals<br />Work-related goals<br />Less movement <br />More movement<br />Understanding Mobile Contexts, Presented for Mobile HCI 2003 Antti Oulasvirta<br />
    7. 7. First academic studies<br />Kristoffersen & Ljungberg (1999). Making place to make “IT” work.<br />Pascoe et al. (2000). Using while moving: HCI issues in fieldwork environments<br />O’Hara et al. (2001). Dealing with mobility: Understanding access anytime, anywhere<br />Tamminen et al. (2004). Understanding mobile contexts.<br />
    8. 8. Understanding Mobile Contexts, Presented for Mobile HCI 2003 by Antti Oulasvirta<br />I Situational Acts Within Planned Ones<br />A<br />Sidestepping triggered by a contextual cue (here: a birthday card on a window)<br />Popping in to a store<br />Sidestepping does not override main goals<br />Sidestepping often socially motivated<br />B<br />Ad hoc meetings<br />
    9. 9. Understanding Mobile Contexts, Presented for Mobile HCI 2003 by Antti Oulasvirta<br />IIa Claiming Personal Space<br />The person is available for others<br />The claiming act: a newspaper is picked up and gazed at<br />The act transforms the sphere around the person to personal<br />Contents of her attention is private<br />The person is not available to others<br />
    10. 10. Understanding Mobile Contexts, Presented for Mobile HCI 2003 by Antti Oulasvirta<br />IV Temporal Tensions<br />Users must get from point A to point B in time t<br />Time and space are overemphasized in mobility<br />Temporal tensions emerge<br />Normal (anticipated) proceeding<br />Acceleration<br />Hurrying<br />Waiting<br />
    11. 11. Understanding Mobile Contexts, Presented for Mobile HCI 2003 by Antti Oulasvirta<br />IVa Hurrying <br />Physical and social surroundings change rapidly<br />Attention is directed mainly to space and time<br /><ul><li> Monitoring time
    12. 12. Selecting the shortest route
    13. 13. Anticipating changes in the environment</li></ul>+ Informing related persons for being late<br />Multitasking cognitively restricted<br />
    14. 14. Understanding Mobile Contexts, Presented for Mobile HCI 2003 by Antti Oulasvirta<br />IVb Waiting<br />End signal must be detected<br />Otherwise, multitasking is socially restricted<br />and most cognitive resources are free for ”time killing” activities<br />In our data, waiting periods were most often utilized by reading or calling a friend<br />
    15. 15. Understanding Mobile Contexts, Presented for Mobile HCI 2003 by Antti Oulasvirta<br />V Multitasking<br />Navigation requires cognitive resources<br />visual attention<br />working memory<br />problem solving<br />More multitasking during waiting than moving<br />
    16. 16. Dynamic<br />Reactive<br />Embodiment<br />Human-Computer-EnvironmentInteraction<br />Movement<br />
    17. 17. Societal<br />Social<br />Experienced<br />Cognitive<br />Behavioral<br />Biological<br />Physical<br />Dynamic<br />Reactive<br />Embodiment<br />Human-Computer-EnvironmentInteraction<br />Movement<br />
    18. 18. Design challenge<br />Ensure information has its intended effect at the right moment<br />Maximize users’ ability to use information at will<br />Elegantly design “through the layers” of mobility<br />
    19. 19.
    20. 20. 1. Walking vs. Interaction<br />
    21. 21. “Human walking is a risky business. Without split-second timing man would fall flat on his face; in fact with each step he takes, he teeters on the edge of catastrophe” <br />(John Napier)<br />
    22. 22. The multiplex of human mobility<br />Prof. Colwyn Trevarthen<br />
    23. 23. Mutual distraction<br />What is the effect of a mobile device?<br />Distracts head control<br />Distracts use of hands<br />What is the effect of walking?<br />Lateral sway of mobile device<br />Impedes visual acuity & attention<br />
    24. 24.
    25. 25. Studies<br /> From standing/sitting to WALKING<br />1923s text entry completion time [1]<br />1813wpm w/ multimodal UI (speech+tap) [2]<br />2015wpm with a mini-QWERTY [3]<br />19% menu selection times [4]<br />459603ms target selection time [5]<br />1730% error in target selection w/ stylus [6]<br />20% audio target selection with gestures [7]<br />2630s reading time [8]<br />2723chrs/s reading speed [9]<br />Similar errors to motor-impaired PC users [10]<br />[1] Hoggan & Brewster, & Johnston 2008, [2] Vertanen & Kristensson 2009, [3] Yatani & Truong 2007, [4] Kane, Wobrrock , & Smith 2008, [5]Schildbach & Rukzio 2010, [6] Lin, Goldman, Price, Sears, & Jacko 2007, [7] Marentakis & Brewster 2006, [8] Barnard, Yi, Jacko, & Sears 2007, [9] Mustonen, Olkkonen, & Häkkinen 2004, [10] Yesilada, Harper, Chen, & Trewin 2010<br />
    26. 26. Reading<br />Study by Mustonen et al. (2004)<br />
    27. 27. What happens to target acquisition?<br />
    28. 28. Preferred Walking Speed<br />longer<br />step<br />shorter<br />step<br />Cavanagh & Williams (1982)<br />
    29. 29. Walking<br />Bergstrom-Lehtovirta, Oulasvirta, & Brewster (2011) Proc. Mobile HCI’11<br />Bergström-Lehtovirta, Oulasvirta, & Brewster (2011) Proc. MobileHCI’11<br />
    30. 30. Design implications<br />ALWAYS A COST for mobile interaction <br />About 60-80% of preferred walking speed is the “optimal trade-off point”<br />Dont’ assume that your system is used while walking<br />If you do, UI elements should be AS LARGE AS POSSIBLE<br />
    31. 31. 2. Attention<br />Visual occlusion<br />Multimodal flexibility<br />Multitasking<br />Inattentional blindness<br />
    32. 32. Neural systems of 3D spatial control<br />2m- distant<br />Upper 360°<br />0.2m- distant<br />Central 20-30°<br />Navigation, scene memory, target orientation<br />Visual, auditory<br />Head movements<br />Visual search, object and face recognition<br />Visual<br />Saccades<br />Visual grasping, manipulation, consumption<br />Visual, proprioceptive, vestibular<br />Arm movements, smooth eye movements, head movements<br />Spatial orientation, postural control, locomotion<br />Visual, vestibular, proprioceptive<br />Leg movements<br />0-2 m<br />Lower central 60°<br />Most distant<br />Front 180°<br />Previc 1998 Psych Review<br />Previc 1998<br />
    33. 33.
    34. 34. The visual occlusion technique<br />Senders 1967<br />
    35. 35.
    36. 36. Visual sampling (video) <br />From Oulasvirta et al. (2005) Proc. CHI’05<br />
    37. 37. Blindfolding world’s best texter<br />From Oulasvirta & Bergstrom-Lehtovirta (2010) Proc. CHI2010<br />LG Texting World Championships 2010<br />
    38. 38. Blocking methodology<br />
    39. 39.
    40. 40. Multimodal Flexibility<br />Ear protection<br />Cardboard<br />Plastic layer<br />Oulasvirta & Bergström-Lehtovirta 2010<br />
    41. 41. Bimodality indices<br />From Oulasvirta & Bergstrom-Lehtovirta (2010) Proc. CHI2010<br />
    42. 42. 3. Multitasking<br />
    43. 43.
    44. 44. Attention and multitasking<br />The resource pool theory of Navon<br />
    45. 45. The Multiple Resources Theory of C.D. Wickens<br />
    46. 46. Argumentation Outline<br />Mobile situation<br />A number of tasks to manage<br />Cognitive resource competition<br />Fragmentation of attention<br />Breakdown of interaction<br />Adoption of compensatory strategies<br />
    47. 47. Reitti<br />
    48. 48. The Fragmented Nature of Attention in Mobile HCI 46<br />Hypothesis<br />We’ll be looking at mobile web browsing where visual and motor resources are most important<br />Use situations with more visual and motor demands involve more fragmentation<br />visual: walking, waiting, avoiding collisions, way-finding, personal space<br />motor: walking, avoiding collisions, maintaining posture<br />We can compare situations from this perspective to make relative predictions on fragmentation of HCI<br />Difference: no walking, just maintaining body posture<br />Difference: sitting down; some management of personal space<br />Difference: no mobility tasks; no external distractions; zero fragmentation<br />Busy street > Escalator > Cafeteria > Laboratory<br />Oulasvirta et al. (2005) Proc. CHI’05<br />
    49. 49. Fragmentation of attention<br />Oulasvirta et al. (2005) Proc. CHI’05<br />Oulasvirta, Roto, Tamminen, & Kuorelahti 2005<br />
    50. 50. The Fragmented Nature of Attention in Mobile HCI 48<br />Output video, data<br />Oulasvirta et al. (2005) Proc. CHI’05<br />
    51. 51. Coding<br />1. LocationOne of the nine exp. places<br />2. User input Starts / stops commanding<br />6. Visual gazePhone / environment<br />3. Page loading statusLoading / loaded w just text / loaded w all content<br />5. CrowdednessNo people around / some passive people around /more people, more active /crowdy, people move close by<br />4. Mode of movementStanding / sitting /normal walk / decelerated walk /<br />(Accuracy about ±1 seconds)<br />Oulasvirta et al. (2005) Proc. CHI’05<br />
    52. 52. Oulasvirta et al. (2005) Proc. CHI’05<br />
    53. 53. Oulasvirta et al. (2005) Proc. CHI’05<br />
    54. 54. The Fragmented Nature of Attention in Mobile HCI 52<br />Crowdedness (r=.25)<br />Oulasvirta et al. (2005) Proc. CHI’05<br />
    55. 55. Patterns of time-sharing<br />Oulasvirta et al. (2005) Proc. CHI’05<br />
    56. 56. Inattentional blindness<br />
    57. 57. The unicycling clown experiment<br />
    58. 58. Design challenge<br />How complex is the environment?<br />Can the critical information be extracted in 0.5-1.5 s?<br />Is simultaneous attention to environment required? <br />UI support for postponing and interleaving tasks<br />
    59. 59. 4. Manual resources<br />
    60. 60. Working 3.5h<br />Leisure and free time 5.3h<br />Purchasing goods 0.8h<br />Eating and drinking 1.2h<br />Educational activities 0.5h<br />Taking care of family members 0.5h<br />Household 1.8h<br />Leisure and free time 5.3h<br />
    61. 61. Human hand model<br />
    62. 62. Manual Multitasking Test<br />A test battery with 12 tasks, derived from<br />Statistics of time use<br />A human hand movement model<br />Oulasvirta & Bergstrom-Lehtovirta (2011) Proc. CHI’11<br />Oulasvirta & Bergström-Lehtovirta (2011)<br />
    63. 63.
    64. 64. Comparing 3 input interfaces<br />Stylus<br />Touchscreen<br />QWERTY<br />Oulasvirta & Bergstrom-Lehtovirta (2011) Proc. CHI’11<br />
    65. 65. Design implications<br />Which objects are your users carrying and manipulating?<br />Which form factor would distract them least?<br />
    66. 66. 5. Information Foraging<br />
    67. 67.
    68. 68. Peter Pirolli<br />
    69. 69. The optimal foraging strategy?<br />“An animal will forage so long as the expected rate of gain within a patch is greater than the expected rate of gain from going to a new patch.”<br />tb= average time to next patch<br />t* = optimal time to stop foraging a patch<br />From Peter Pirolli’s slideset available in the internet<br />
    70. 70. Information<br />Energy<br /><ul><li>Prey vary by profitability.
    71. 71. Environment may be patchy.</li></ul>Energy = information<br />From Peter Pirolli’s slideset available in the internet<br />
    72. 72. “If time / distance between patches is reduced, optimal time in any one patch is shorter”<br />tba<br />tbb<br />From Peter Pirolli’s slideset available in the internet<br />
    73. 73. “If patch abundance is increased, optimal time in any one patch is reduced”<br />tb<br />More information faster equals lower tolerance to search!<br />One will quickly browse, and go with the closest match, or go elsewhere if information is not readily available.<br />
    74. 74.
    75. 75. Cognitive model<br />new<br />cell<br />Information<br />Goal<br />medical<br />patient<br />Link Text<br />treatments<br />dose<br />procedures<br />beam<br />Spreading activation in associative network<br />From Peter Pirolli’s slideset available in the internet<br />
    76. 76. Temporal scales<br />Newell<br />Psychological<br />domain<br />Time scale <br />(s)<br />107<br />106<br />105<br /><ul><li>SOCIAL</li></ul>104<br />103<br />102<br /><ul><li>RATIONAL(Adaptive)
    77. 77. Task</li></ul>101<br />100<br />10-1<br /><ul><li>Unit task
    78. 78. Operations
    79. 79. Visual attention
    80. 80. COGNITIVE(Proximal Mechanisms)</li></ul>From Peter Pirolli’s slideset available in the internet<br />
    81. 81. When should I change the patch?<br />Cumulative gain<br />g(tW)<br />R*<br />R2<br />R1<br />t1<br />t*<br />t2<br />tB<br />tW<br />Between-patch time<br />Within-patch time<br />From Peter Pirolli’s slideset available in the internet<br />
    82. 82. Charnov’s marginal value theorem<br />“Max gain when slope of within-path gain g = average gain R (tangent in diagram)”<br />Gain<br />R*<br />g(tW)<br />Within-patch<br />time<br />Between-patch<br />time<br />tB<br />t*<br />From Peter Pirolli’s slideset available in the internet<br />
    83. 83. Information scent<br />Tokyo<br />“Cues that facilitate orientation, navigation, assessment of information value”<br />New York<br />San Francisco<br />From Peter Pirolli’s slideset available in the internet<br />
    84. 84. Example: File system<br />9<br />8<br />Hyperbolic Browser<br />7<br />Slope = 1.09 levels/sec<br />6<br /> = 0.92 sec/level<br />5<br />Level<br />4<br />3<br />Slope = 0.57 levels/sec<br /> = 1.75 sec/level<br />2<br />Explorer Browser<br />1<br />0<br />0.00<br />2.00<br />4.00<br />6.00<br />8.00<br />Time (Sec)<br />Hyperbolinen puu<br />Microsoft File Explorer<br />From Peter Pirolli’s slideset available in the internet<br />
    85. 85. Spreading activation in associative networks<br />~ 200 X 200 million sparse “word” matrix<br />Document<br />corpus<br />Word<br />statistics<br />Spreading<br />activation<br />network<br />~ 55 million associations<br />From Peter Pirolli’s slideset available in the internet<br />
    86. 86. Spreading activation<br />Activation of node i<br />Ai = Bi + WjSji<br />Base-level<br />activation<br />Activation spread<br />from linked nodes j<br /> Pr(i)<br />Pr(not i)<br />Bi = ln( )<br />i<br />“bread”<br />j<br />“butter”<br /> Pr(j|i)<br />Pr(j|not i)<br />Sji = ln( )<br />Base-level reflects likelihood of occurrence<br />Strength of link spread reflects likelihood<br />of cooccurrance<br />From Peter Pirolli’s slideset available in the internet<br />
    87. 87. Design challenge<br />How does the structure of and cues in the environment support the user finding targets?<br />How well do your system’s cues match to the cues available in the environment?<br />Direct cueing? (e.g., photo of a landmark, name of a street)<br />Indirect cuieing? (e.g,. audio cue of direction)<br />
    88. 88.
    89. 89. 6. “Embodied interaction”<br />
    90. 90. Basic problem<br />Making geo-referencing data understandable & actionable in the physical context<br />Oulasvirta et al. (2009) Embodied interaction with 3D vs 2D mobile maps. PUC<br />
    91. 91.
    92. 92. In situ recognition of mobile imagery (focal extrapersonal space)<br />Unpublished work<br />Oulasvirta, Nurminen, & Suomalainen (submitted) IEEE Multimedia<br />
    93. 93. Experiments with a 3D mobile map<br />2D<br />3D<br />Oulasvirta, Estlander, & Nurminen 2009<br />
    94. 94. Video<br />Oulasvirta, Estlander, & Nurminen 2009<br />
    95. 95. Kirsh & Maglio 1994<br />
    96. 96. Strategies of embodied interaction<br />”Bookmarking” the map with index finger<br />Rotation in hand<br />Oulasvirta, Estlander, & Nurminen 2009<br />

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