Dr. Hui Wang Wanghui@ios Dec.26, 2004

1. Designing Affordances in UbiComp Dr. Hui Wang Wanghui@ios.cn Dec.26, 2004

2. Outline • Ubiquitous Computing • Affordance • Affordance in HCI • Affordance in UbiComp • Future Study • Narrow Broadcasting, New Challenge

3. Development of Computers Picture from http://www.ubiq.com/hypertext/weiser/weiser.html

4. 无处不在计算中人机交互的核心 • 无处不在 Ubiquitous Computing • 发生在物理环境中, The World is not a Desktop. • 看不见的计算 Invisible Computing • You don’t know you are using computers when you use them. Unconscious Interactions based on Unconscious Cognition.

5. 人类活动模型 Understanding human action 1. Establishing the goal to be achieved 2. Forming the intention for the action that will achieve the goal 3. Specifying the action sequence corresponding to the action 4. Executing the action 5. Perceiving the system state 6. Interpreting the system state 7. Evaluating the system state with respect to the goal and intentions. (Norman, D: The Design/The Psychology of Everyday Things, 1988)

6. 执行和评估的鸿沟 Gulfs of execution and evaluation 执行鸿沟:用户的目标和通过系统达到目标的手段之间的距离。distance between user’s goals and the means of achieving them through the system 评估鸿沟:判断系统状态所需要花费的精力，是否获得期望结果。the amount of effort required to determine the system state; did it do what the user wanted in the way they expected?

7. 如何实现？Affordances • 无意识认知 Automatic • 快; 需要很少的注意力; 不干扰其它活动 • 自动的过程 • 一旦学好难以改变 • 有意识认知 Controlled • 需要较多注意力和有意识的控制 • 容易改变 • Stroop 效应：一个自动认知过程(无意识认知)会与另一个认知过程发生冲突。目前的WIMP交互范式难以实现无意识交互，无意识交互是填补鸿沟的方法。

8. Outline • Ubiquitous Computing • Affordance • Affordance in HCI • Affordance in UbiComp • Future Study • Narrow Broadcasting, New Challenge

9. Lack of Affordance – Example What in the world is this glass for?

10. Now with an Affordance!! This sure makes it obvious!

11. What is Affordance? • First coined by J.J Gibson in 1979: "The affordances of the environment are what it offers the animal, what it provides or furnishes, either for good or ill. The verb to afford is found in the dictionary, but the noun affordance is not. I have made it up. I mean by it something that refers to both the environment and the animal in a way that no existing term does. It implies the complementarity of the animal and the environment...

12. 视觉感知理论 Visual perception Theories • Constructive theorists: the process of seeing is active; view of the world constructed from info in environment and previously stored knowledge • Ecological theorists: perception involves the process of picking up info from the environment; doesn’t require construction or elaboration (生态学方法认为认为感知是一个直接的过程，可以作为无意识人机交互的一个理论基础) • Ecological Psychology -- JJ Gibson • People developed in the real world • Human perceptual ability shaped strongly by features of the natural world

13. An Evolutionary theory of psychology • An Evolutionary theory of psychology • Natural selection gave us abilities to recognize and manipulate tools • Information-Foraging Theory • Information scent • The economics of attention and cost structure of information. Natural and artificial information systems evolve toward states that maximize the delivery of more valuable information per unit cost

14. Gibson’s Affordances • An affordance exists relative to the action capabilities of a particular actor. • The existence of an affordance is independent of the actor’s ability to perceive it. • An affordance does not change as the needs and goals of the actor change. • Affordances are provided by the environment, and hence are physical.

15. Affordance as perceived, cultural (Norman) • “Affordance refers to the perceived and actual properties of the thing…..” Donald Normana, Psyhcology of Everyday Things • Logical constraints and cultural convention also influence what an object “affords”

16. Outline • Ubiquitous Computing • Affordance • Affordance in HCI • Affordance in UbiComp • Future Study • Narrow Broadcasting, New Challenge

17. Affordances and HCI • Affordances in HCI: “An aspect of an object which makes it obvious how it should be used.” • Perceived affordance in HCI can be more significant than real affordance • Keep the perceptions of the user in mind. “Just the right things have to be visible: to indicate what parts operate and how, to indicate how the user is to interact with the device. Visibility indicates the mapping between intended actions and actual operations." ( D. A. Norman, The Psychology of Everyday Things (New York: Basic Books, 1988)

18. Affordance Discussion continued • it is required that every individual visible feature provides recognisable affordance.

19. Affordance Discussion continued • User's knowledge of affordances of real world objects used to create visually significant & perceptive environments using metaphors & analogies. • User’s ability of direct manipulation of objects presented on the GUI gives feeling of security and control

20. Examples of Affordance in Product Design How do we Zoom in ?

21. Examples of Affordance Continued How do we Zoom in ?

22. Examples of Affordance Continued Bad Affordance … Why? Neither the “Site Map” or “Help” Buttons have an indication of there affordance.

23. Outline • Ubiquitous Computing • Affordance • Affordance in HCI • Affordance in UbiComp • Future Study • Narrow Broadcasting, New Challenge

24. Affordances in Ubiquitous Computing • Physical environment • Mobile or short stay • Informal Interaction • DC and Affordance

25. Distributed Cognition 1 • Extends what is a “cognitive system” beyond the individual and includes • Resources and materials of the environment • Three principles • 1) Unit of analysis extends beyond the individual to bring subsystems into coordination to accomplish a goal: functional relationship of all participants

26. Distributed Cognition 2 • Second principle: range of participants is large – no longer simply “symbol manipulation within single actors” but extends to animate and inanimate actors and materials • E.g external memory aids • Cog processes: distributed across a social group; internal and external coordination; or organized over time.

27. Approach or Method of Distributed Cognition • Cognition is embodied: • We are not passive information transformers • Coordination among time scales and processes to stabilize the world and assign meaning to it. • JJ Gibson defined affordances as the meaningful interactions among organisms and the world: how are we able to recognize complex shapes and forms while moving through the world? • Artifacts are often melded into the way we see the world – blind mans cane

28. 超越ＷＩＭＰ范式的Affordance • Perceptive Affordance (计算机输出) 生态学方法认为认为感知是一个直接的过程，可以作为无意识人机交互的一个理论基础。Perception involves the process of picking up info from the environment; doesn’t require construction or elaboration • Action Affordance (计算机输入)具体化的交互(Embodied Interaction)可以提供操作Affordance。Paul Dourish ,Where The Action Is: The Foundations Of Embodied Interaction. Mit Press, 2001 Figure from Joanna McGrenere , Affordances: Clarifying and Evolving a Concept. GI 2000

29. 例子 Examples

30. Information Processing Model

31. Designing Affordance in UbiComp

32. Information Processing Model with ANN

33. Activity-centered Affordance • A new Information Processing Model which could take into account of Affordances. • Attention Management study

34. Scandinavian’s Activity Theory 1 • The role of the artifact as it stands between the user and her materials, object, and outcome was ill understood. • The idealized models created through task analysis failed to capture the complexity and contingency of real-life action. • From automation. Craftsman surrounded by his tools and material.

35. Scandinavian’s Activity Theory 2 • Analysis and design for a particular work practice with concern for qualifications, work environment, division of work. • Analysis and design with focus on actual use and the complexity of multiuser activity. The Notion of the artifact as mediator of human activity is essential • Active user participation in design, and focus on use as part of design.

36. Future Study • Enhanced Info Processing Model • Info Processing Model with NN • Activity-centered Affordance

37. Introduction of Signage • 随着计算机技术特别是网络、多媒体技术的发展，及显示设备的多样化，使媒体信息播放逐渐走出专业领域，从而导致了signage系统的迅速发展。 • Signage系统具有信息数字化，管理集中化，播放终端分散布置等特点。 • Narrow Broadcasting

38. 播放信息 • 文字信息，有动态文字与滚动文字之分，可以有多种播放效果 ; • 图像和动画信息; • 视频信息，包括多种格式的视频信息;

39. 系统硬件及操作系统要求 • 1、配套硬件: 根据系统总体设计要求，配置相应硬件。播放端建议采用微型PC，可以直接安装于显示终端背后。主机速度和显示卡性能能够满足商业应用的一般需要。考虑无线网络功能，有一定可扩展性。高可靠性，适应7X24运行。设计上考虑自我保护问题，避免在使用端，被误操作或恶意操作，减少不必要外置操作按键。 • 2、操作系统: 采用主流操作系统。播放端建议采用嵌入式操作系统。可以由远端控制开关机，系统开机后直接进入程序界面，本地免操作。

40. 功能说明 • 根据功能整个系统可划分为三个子系统，分别为：编辑制作系统、网络管理系统以及信息播放系统。系统存储格式采用XML，提供完善的网络功能，能够根据系统规模大小灵活配置，使整个系统适合于不同的实际需要。

41. HCI Study • Context-awareness computing • Online • Off-line • Scenario Design

42. Thank You!

43. To be the First • "I once asked Ivan, 'How is it possible for you to have invented computer graphics, done the first object oriented software system and the first real time constraint solver all by yourself in one year?" And he said "I didn't know it was hard."-- Alan Kay on Ivan Sutherland. • The best way to predict the future is to invent it (...uttered by Kay in 1971 at a Xerox planning meeting.)

44. Beyond Calculation, the next 50 years of computing From Computing Machinery to Interaction Design Terry WinogradStanford University Published online by permission from Peter Denning and Robert Metcalfe (eds.), Beyond Calculation: The Next Fifty Years of Computing, Springer-Verlag, 1997, 149-162.

45. Directions of change • Computation to communication • Machinery to habitat • Aliens to agents