1 interactive systems design msc in communications, computing and human-centred systems dr. chris...

Post on 14-Dec-2015

215 Views

Category:

Documents

0 Downloads

Preview:

Click to see full reader

TRANSCRIPT

1

Interactive Systems Design

MSc in Communications, Computing and Human-Centred Systems

Dr. Chris Baber

2

Human-Centred Systems

Dr Chris Baber

Room: N313 Tel. ext.: 43965

Email: c.baber@bham.ac.uk

3

Aims

Introduce some basic concepts from Cognitive Psychology

Demonstrate relationships between these concepts and interactive systems design

4

Objectives

After completing this module, students will be able to:

Critique user interfaces through the application of appropriate concepts from cognitive psychology

Offer guidelines on how to improve a design

5

Assignment1. Select ANY mobile telephone user interface

2. Critically evaluate the user interface in terms of:1. layout 2. use of colour3. Gestalt 4. consistency 5. support for navigation

3. Explain how and why the user interface might present problems to users

4. Consider the (non-computer) metaphor(s) that can be related to the design

5. Explain what assumptions you believe that the designers have made in terms of the way that users interpret the user interface

6. Produce a redesign of the user interface that you believe is superior to the current version and explain why your redesign is better

6

Marking Scheme

1. Presentation of system image and screen-shots (images and description) - up to 10 marks

2. Definition of a ‘good’ user interface - up to 10 marks3. Discussion of key topics from cognitive psychology -

up to 30 marks4. Critique of selected user interface, in terms of 2 and

3 - up to 25 marks5. Redesign (images and description) - up to 10 marks6. Why is your redesign superior to the current design?

- up to 10 marksUp to 5 additional marks for presentation of report

7

Useful References

Ji, Y.G. et al., 2006, A usability checklist for the usability evaluation of mobile phone user interface, International Journal of Human-Computer Interaction, 20 (3), pp. 207-231

Bocker, M. and Suwita, A., 1999, The evaluation of the Siemens C10 mobile phone – usability testing beyond ‘quick and dirty’, Proceedings of the 43rd Annual Meeting of the Human Factors and Ergonomics Society, Santa Monica, CA: HFES, pp.379-383

Ziefle, M., 2002, Usability of menu structures and navigation keys in mobile phones: a comparison of the ease of use in three different brands, Proceedings of the 6th International Scientific Conference on Work with Display Units, Berlin, pp.359-361

Jokela, T. et al., 2006, Methods for Quantitative Usability requirements: a case study on the development of the user interface of a mobile phone, Personal and Ubiquitous Computing, 10 (6), 345-355

8

TimetableMonday 29th Tuesday 30th Wednesday 31st

10 - 11 1. Introduction to Module

6. Navigation in user interfaces

10. Paper prototyping

11 - 12 2. Fundamentals of graphical user interface

design

7. Interaction Devices: entering

data

11. Distributed Cognition

12 - 1 3. Link and Layout Analysis

8. Interaction Devices:

Selecting objects

12. Collaborative Work

2 - 3 4. Use of Colour and Highlighting

9. Multimodal HCI 13. Future HCI

4 - 5 5. Commands and Menus

10. Mobile HCI 14. Future HCI

9

1. Introduction

10

Design Principles1. Know your user2. Build on systems that are familiar to your user3. Display available functions4. Ensure Coherence and Consistency5. Visualise states and transitions6. Design shortcuts7. Design Help8. Tolerate user error9. Provide Context10. Manage Focus11. Display Grammar

11

Varieties of TechnologyTechnology mediates human action

on the world in ways that…

Augment

Correct

Extend

Modify

& Disrupt

…human performance and ability

12

Augment / Correct / Extend

Technologies ‘augment’ human abilities SUBSTITUTION: calculators

REPRESENTATION: shopping lists

Technologies ‘extend’ human abilities CORRECTION: spectacles, hearing aids

increasing RANGE: telescope, telephone

13

Modify

Technology changes: Task sequence Required actions Information content

Example: Calculate 9 hours of work at £3.50 per hour.

What if you add another hour?

14

Disrupt

Changes ways of working Requires new ways of thinking or acting

Interferes with activities MicroSoft PaperClip PDA in meetings Mobile phones in lectures

15

How different ‘models of the user’ lead to different assumptions on how to Minimise Human Error

Explain error Reduce error

Idiot Design fault Make as simple as possible

Designer Error free No need

Computer Follow instruction Clarify instruction

Information Processor Breakdown Modes; forcing functions

Active Interpreter Not Compatible Design for mental model

16

‘Instant Experts’

You get a new mobile telephone for Xmas, do you:

1. Read the manual from cover to cover and then switch on the phone?

2. Switch on the phone and try to use it?

3. Switch on the phone and read the manual when you have problems?

17

Using tools

Physical appearance

Knowledge of use

Sequence of activity

18

Affordance

See handle Reach out hand Grasp handle Turn handle Pull door

19

The Cooker Problem #1

Which control acts on which ring?

20

The Cooker Problem #2

Which control acts on which ring?

21

Paul Fitts: Spatial Compatibility

22

Direction of motion Stereotypes

a d

b

c

? ?

Clockwise = increaseClockwise = rightClockwise = away from controlClockwise = increase on scale

1 2 3 4 5 67

1 2 3 4 5 67

23

Clockwise to Increase?

1234567

24

Conclusions…

We have learned ‘routines’ for how to use many sorts of technology

We apply these routines ‘automatically’ When the routines succeed, they are

reinforced When the routines fail, we think about what

we’re doing

25

Expectations and Affordances

People “know” how technology works…

‘Out of box’ experience

Reading instructions

Prior knowledge and expectations

26

Automaticity

Norman and Shallice (1980) Fully automatic processing controlled by SCHEMATA

Partially automatic processing controlled by either Contention Scheduling

Supervisory Attentional System (SAS)

27

Supervisory Attentional System Model

Perceptual System

SupervisoryAttentional

System

Effector System

Contentionscheduling

Triggerdatabase

Control schema

28

Contention Scheduling

Gear changing when driving involves many routine activities but is performed ‘automatically’ – without conscious awareness

When routines clash, relative importance is used to determine which to perform – Contention Scheduling

e.g., right foot on brake or clutch

29

SAS activation

Driving on roundabouts in France Inhibit ‘look right’; Activate ‘look left’ SAS to over-ride habitual actions

SAS active when: Danger, Choice of response, Novelty etc.

30

Know your user…

When designing any form of user interface, you should ask:

What am I trying to help the reader (or user) of this display do?

How does the information I am presenting to them help with their thinking or their activity?

31

Seven Stage Action Model[Norman, 1990]

Form intentionDevelop plan

Perform action

Object in world

Evaluate against goalInterpret object

Perceive state of object

GOAL OF PERSON

32

Routes from Intention to Action

Route 1:Automaticity Apply known routine Compatibility Affordance

Route 2: Formulate plan Problem solving Situated actions

33

Problem Solving

A problem is something that doesn’t solve easily

A problem doesn’t solve easily because: you don’t have the necessary knowledge or, you have misrepresented part of the problem

If at first you don’t succeed, try something else

Tackle one part of the problem and other parts may fall into place

34

Problem Solving

Representation affects strategy

More than one possible solution

Solution limited by boundary conditions

Active involvement and testing

35

Problem

SEND

+ MORE

MONEY

36

Functional Fixedness

Strategy developed in one version of the problem

Strategy might be inefficient

XIV ÷ X vs. XXXX ÷ X

Convert numerals or just ‘see’ 4

37

Interacting with Products as Problem Solving User has a ‘goal’ to achieve using the product

The product offers functions to the user

The user must select the ‘best’ function to progress towards the goal

The interaction can be thought of as movement through a space of possible actions towards a goal

Selection of the ‘best’ action will be influenced by available functions and their interpretation

38

Situated Actions

‘Plans’ imply a specified sequence of actions… plans are representations of action

…but some actions are ‘opportunistic’, i.e., supported by the current context-of-use

Suchman (1992) terms these ‘situated actions’ plans are resources for action

39

2. Fundamental of graphical user interface design

40

Information Design can Influence Thinking

John Snow, 1854m Mapping death from cholera, in London, showed clusters around water pump (and not near brewery)

41

Attributes affecting utility

ReadabilityWordsSyntax

LegibilityFont design

ContrastIlluminationLuminance

ConspicuityGraphic designSpatial coding

Temporal codingShape codingColour coding

Display

Psychological processExtraction of meaning

Comprehension

Mediating Userattributes

42

Gestalt Principles

43

Density and Clutter

Density is related to available screen space E.g 80 x 24 line display = 1920 character spaces

The proportion of filled spaces = Density Density averages 25% but rarely exceeds

50%

44

Levels of Density

70% density 50% density 30% density

Shneiderman, 1992

45

Reducing Density

Grouping / tabulating; Reduce number of words; Reduce number of characters

46

Conclusions

Understanding basic Gestalt principles helps manage focus

Some objects on a display are more conspicuous than others Use highlighting sparingly

Some objects form ‘perceptual groups’ Use this to help design screen layout and to

minimise risk of confusion

47

3. Link and Layout Analysis

Link Analysis Sequence in which objects are used, or attended

to, during a task Data recorded from eye-movement or from

observation of product use Layout Analysis

Define relationship between objects in terms of functional grouping and sequence of use

48

3. Link and Layout Analysis

49

Eye-Movement ‘Heat Maps’

50

Reading

Saccades and Fixations

Anticipation and Inferences

Interpretation

51

Saccades and Fixations

52

Reading from Computer Screens

Reading Speed Computer 20% - 30% slower than paper

BUT only when Refresh rate < 60Hz Resolution < 640x480 pixels

Differences essentially related to character discrimination data-driven perception (see slide 27)

53

Link Analysis Worked Example:scan of initial layout

Cassette door

Radio displayBANDASPMME-SCAN

ST

DX/LOA

SCAN

SEEK

CD

1 2 3

4 5 6B

54

Link Analysis Worked Example:revised layout

Cassette door

Radio display

BANDASPMME-SCAN

ST

DX/LO

A

SCAN

SEEK

CD 1 2 3

4 5 6

B

55

Layout Analysis Worked Example:initial layout

Cassette door

Radio displayBANDASPMME-SCAN

ST

DX/LOA

SCAN

SEEK

CD

1 2 3

4 5 6B

56

Layout Analysis Worked Example:functional grouping

Cassette door

Radio displayBANDASPMME-SCAN

ST

DX/LOA

SCAN

SEEK

CD

1 2 3

4 5 6B RADIO

RADIO

CASSETTE

57

Layout Analysis Worked Example:redesign within functional groupings

Radio display

BANDASPMME-SCAN

ST

DX/LOA

SCAN

SEEK

CDCassette door

1 2 3

4 5 6

B

58

Context

When presented with ambiguous stimuli our prior knowledge of the world helps us to make sense of it

59

Context

60

InterpretationKnowledge of what you are “looking at” can aid in interpretation

JA CKAN DJI

LLW ENTU PTH

EHI LLTOFE

TCH APAILO

FWA TER

Organisation of information is also useful

A B C

1 20 15 10

2 32 16 12

3 27 17 11

Gestalt also influences interpretation

61

Concepts

How do you know a chair is a chair?

A chair has four legs…does it? A chair has a seat…does it?

62

Mental models

Craik Internal representation of external reality Every good monitor needs a model of the world it

is monitoring Johnson-Laird

Strategies of knowledge assimilation

63

Mental Models

Van Dijk and Kintsch (1983) Text processed to extract propositions, which are

held in working memory; When sufficient propositions in WM, then linking

performed; Relevance of propositions to linking proportional

to recall; Linking reveals ‘gist’

64

Inferences

Comprehension typically requires our active involvement in order to supply information which is not explicit in the text

1. Mary heard the ice-cream van coming

2. She remembered her pocket money

3. She rushed into the house.

65

Inference and Recall

Thorndyke (1976): recall of sentences from ‘Mary’ story 85% correct sentence 58% correct inference –

sentence not presented 6% incorrect inference

66

Scripts, Schema and Frames Schema = chunks of knowledge

Slots for information: fixed, default, optional

Scripts = action sequences Generalised event schema (Nelson, 1986)

Frames = knowledge about the properties of things

DESIGN CAN HELP CALL APPROPRIATE CONCEPTS TO MIND, e.g., through the use of metaphor

67

VisiCalc Xerox Star

68

WIMP

Windows Icons Menus Pointing devices

69

Metaphor - Pros

WOZNY (1989) Metaphors allow users to compare knowledge of the world

with what is happening in the system, and use analogy in initial reasoning with the system

MARCUS (1998) “A familiar concept in an unfamiliar environment can add

appeal and when users are new to a topic or application domain, seeing familiar references can reduce tension, stress, boredom, confusion, anxiety, and alienation, while increasing their self-assurance, calm, interest, engagement and dependence upon the user interface.”

70

Designing with Metaphors

MARCUS, 1994 MADSEN,1994 CARROL ET AL. 1988

ORGANISE: provide simple, clear, consistent

metaphors

Listen to how users understand their computer

Identify candidate metaphors

ECONOMISE: maximise effectiveness of minimal

set of metaphors

Build on existing metaphors

Detail metaphor / software matches with respect to

user scenarios

COMMUNICATE: match metaphors to user

capabilities

Use predecessor artefacts as metaphors

Identify likely mismatches and their implications

MANAGE MISMATCHES Note metaphors already implicit in problem

description

Identify design strategies to help minimise

mismatches

71

Smilowitz, “Do metaphors make web browsers easier to use?”

http://www.baddesigns.com/mswebcnf.htm

72

Integral metaphor (library) ‘Standard browser’ interface (no metaphor)

73

Integral metaphor (travel) Composite metaphor (library + travel)

74

Metaphor - Cons

“Those who think that one should use metaphors in design are destined to produce crappy designs.” (DON NORMAN)

PIRHONEN (2003) A metaphor cannot cover the whole domain of the referent

And so limits functionality of the design (HARRISON ET AL. 1998) Once a person has learned the application, the metaphor becomes redundant

HUDSON (2002) Metaphor can lead to inappropriate assumptions on error recovery

COOPER (1995) Searching for the ‘magic metaphor’ can be one of the biggest mistakes an interface

designer can make A Metaphor could offer a tiny boost to learnability at first but eventually limits

functionality There are not enough metaphors to go around Metaphors do not scale well

75

4. Use of Colour and Highlighting

76

Contrast Effects

This text is quite easy to read because the contrast between figure and ground is high

This text is more difficult to read because the contrast between figure and ground is lower

This text is very hard to read because the contrast between figure and ground is minimal

77

Galitz, W.O., 1996, The Essential Guide to User Interface Design Potential problems:

screen backgrounds being more attention grabbing than screen data

overuse of colour as a code (the colour itself meaning something to the screen viewer), which forces the user to interpret a colour’s meaning before the message it is communicating can be reacted to.

78

Galitz, W.O., 1996, The Essential Guide to User Interface Design

Use colour to assist in formatting a screen:

relate or tie elements into groupings break apart separate groupings of information associate information that is widely separated on the

screen highlight or call attention to important information by

setting it off from other information

79

Tufte, E., 1989, Visual Design of the User Interface1. The border of an active window should be light in

value (to avoid clutter with other windows), yet deeply saturated (to provide a conspicuous signal)

2. Yellow is the only colour jointly satisfying both these conditions, and therefore proves valuable for bordering windows

3. A good way to avoid colorjunk is to use colours found in nature, particularly towards the lighter side, such as blues, greys, yellows

4. Nature’s colour are familiar and have a widely accepted harmony

80

Apple Computer Inc., 1992, Macintosh Human Interface Guidelines Use of Colour in Windows:

Distinguishes the active window from other windows and enhances the appearance of user controls on the window frame.

Scroll bars and title bars are gray User controls are coloured to make them more apparent Inactive window borders are gray to make them recede into background and active windows black

border stands out. User can change colours from colour control panel User chosen highlight colours will be used in windows and dialog boxes.

Limit the number of Colours To maintain consistency with operating system, use as few colours as possible. Fewer colours results in less visual clutter on the screen

Colours on Gray Colours look best against a background of neutral gray Colours will stand out more if the background and surrounding areas are gray black, or white

Beware of Blue Light Blue is the colour most difficult to distinguish. Avoided for text, thin lines, and small shapes. If you want things to be unobtrusive, thought, light blue is the perfect colour.

81

Factors that Affect Contrast and VisibilityVariable Effect Example

Contrast Visibility Black print on grey

Illumination Contrast Sensitivity (CS)

Reading map in poor light

Polarity Black on white better than white on black

Designing slides

Spatial frequency Optimum CS at 3 C/D Ideal size of text font given viewing distance

Visual accommodation CS Map reading during night driving

Motion CS Reading a road sign while moving

Wickens et al., 1998, An Introduction to Human Factors Engineering

82

Data-driven perception

Activation of neural structures of sensory system by pattern of stimulation from environment

83

Theory-driven perception

Perception driven by memories and expectations about incoming information.

84

Exercise

x

i. X on outside front cornerii. X on insideback corner

85

Visual Illusions

Old Woman or Young girl?

Rabbit or duck?

http://www.genesishci.com/illusions2.htm

86

KEYPOINT

Perception limits are set by sensory / neural mechanisms; but beyond these limits, perception can be cognitively controlled;

Sensory experiences interpreted in a CONTEXT and derive from a variety of sources

87

Conclusions

Humans constantly seek patterns in the world around them…

…and use these patterns to impose meaning on what they see or hear.

Good design encourages this search for pattern…

…bad design makes people see patterns when none are intended.

88

5. Commands and Menus

89

Commands and Icons

GREP –V ^$filea>fileb

A B

90

Command Languages

Advantages

Fast

Efficient

Precise

Concise

Flexible

User initiated

Disadvantages

Training

Regular use

High memory load

Poor error handling

91

Commands Languages

Command languages rely on recall Draper (1985)

UNIX users poor recall on written test, but excellent recall when using computer

Black and Moran (1982) Learn 8 commands. Performance best for ‘infrequent,

discriminating’ words, e.g., insert, delete. Random words also good.

92

Knowledge in the HeadKnowledge in the World“Menus relieve users of the need to remember

command names, but not of the need to know what functions can be performed by some commands…”

[Mayes et al., 1988]

Knowledge held by users and recalled‘Knowledge’ prompted by objects in world

93

Command Languages Guidelines

Kidd (1982): Choose memorable, nonconfusable command word Use consistent command formats Keep command strings short Provide help Use natural syntax Place optional / least used commands at end of list Ensure useful defaults If errors frequent, then revert to computer initiated

94

Menus

Advantages

Minimal typing

Low memory load

Defined structure

Disadvantages

Speed

Screen space

Poor for data entry

Computer initiated

95

Menus

Single menu Binary options

Do you want instructions? Y / N

Linear sequence Series of interdependent menus

Sequence of forms for printing

Tree structure Semantic network

8 items per menu x 2 levels for time and error

96

Tree structure

Menu Trees reduce error rate when compared with random Search faster over trees than alphabetic or

random Semantic networks

97

Menu Guidelines

Task semantics Meaningful groupings Short cuts Items brief Consistent terminology Headings relevant Limit to 8 items

98

Icons

Concrete vs. Abstract

Reference and interpretation

Verbal labels can speed response

99

Icon design

Marcus (1992) Lexical: pixel shape, colour, blinking Synatatics: lines, pattern, size, shape Semantics: concrete, abstract, part Pragmatics: legibility, utility, identification,

recognition Dynamics: highlighting, selection

100

Icon Guidelines

Represent object in familiar manner Limit number of different icons Make icon conspicuous Ensure selection made clear Ensure icons belong to ‘families’

101

Working Memory Experiments

102

Central executive

Articulatory control process

Auditory word presentation

Visual word presentation

Phonological store

Visual Cache

Inner scribe

Baddeley’s (1986) Model of Working Memory

103

Slave Systems

Articulatory loop Memory Activation Rehearsal capacity

Word length effect and Rehearsal speed Visual cache

Visual patterns Complexity of pattern, number of elements etc

Inner scribe Sequences of movement Complexity of movement

104

Recognition vs Recall

Recall Retrieve from memory

Remembering print command

Recognise To bring back into awareness through prompt

Recognising print icon Recognising print item in menu

105

Recognition vs Recall

“The boxer chewed the meat” Recall: who chewed the meat? Recognition: did the boxer chew the meat?

Recognition easier than recall More information retrieved under recognition

than recall

106

Long Term Memory as a Semantic Network

ANIMAL

Has SkinCan moveEatsBreathes

BIRDCan fly

Has WingsHas feathers

FISHHas finsCan swimHas gillsCANARY

Is YellowCan sing

107

Levels and Reaction time

A canary is a canary

A canary is a bird

A canary is an animal

A canary is a fish

A canary can sing

A canary can fly

A canary has skin

A canary has gills

Collins & Quillian, 1969

0.9

1

1.1

1.2

1.3

1.4

1.5

0 1 2 False

Levels of Sentences

Mean

Reacti

on

Tim

e (

s)

Property

Category

108

Canaries

Different times to verify the statements: A canary is a bird A canary can fly A canary can sing

Time proportional to movement through network

109

Spreading Activation

When searching semantic network, activate paths for search

The active a node, the more easily information can be obtained from it

Semantic Priming Effects

110

Forgetting

Encoding failure Failure of consolidation

Storage failure Disruption by new or existing information Associative interference

Two responses associated with same stimulus

Retrieval failure

111

6. Navigation in User Interfaces

112

Navigating Menus

113

Hypertext

Bush (1945) Nelson (1963) Hyperlinks between objects in

document Navigation

Following links through the document

114

Navigation Aids

115

Searching the World Wide WebScanning modes Information need Information seeking Information use

Undirected Viewing General areas of interest; specific need to be revealed

Sweeping

Scan broadly a diversity of sources, taking advantage of what's easily accessible"

Browsing

Serendipitous discover

Conditioned Viewing Able to recognize topics of interest

"Discriminating"Browse in pre-selected sources on pre-specified topics of interest

"Learning"Increase knowledge about topics of interest

Informal Search Able to formulate simple queries

"Satisfying"Search is focused on area or topic, but a good-enough search is satisfactory

"Selecting"Increase knowledge on area within narrow boundaries

Formal Search Able to specify targets in detail

"Optimizing"Systematic gathering of information about an entity, following some method or procedure

"Retrieving"Formal use of information for decision-, policy-making

http://www.firstmonday.org/issues/issue5_2/choo/#fig1

116

Choice of Aid x Search Style

Hammond and Allinson (1989)

117

Information Foraging

Priolli, P. ,2007, Information Foraging Theory ‘information scent’ left on path of search by users More users on path means more ‘scent’ Users attempt to predict what information will

obtained from following a given path

118

6. Interaction Devices: Entering Data

119

Generic Forms of Interaction

Select Object Drag Object Change Orientation of Object Enter Data

120

ConversationKevin: Want to see that film?

Brian: the uh (500 ms)… with the bloke from that other um that prison thing, [Shaw…]

Kevin: [The Shawshank Redemption] Tim something – [married that bird with the eyes]

Brian: [Robbins](laughs) Yeah…. 'The Green… whatsit?

Kevin: OK. There’s one at uh ... (looks at watch - 1.2 s) ... 20 to?

121

Human Communication

Units of analysis Proposition Lack of ‘proper’ grammar

Adjacency Pairs Question-answer

Turn-taking Over-lapping

Extralinguistic and Paralinguistic cues Back channels Gestures

122

Turn Taking

When it is your ‘turn’? Subtle cues from partner

When they are finishing When they want to speak

Unsubtle cues from machine Speak after beep Respond from list

123

Asymmetrical Conversations

Telephone Short phrases Task oriented Problem of silence

Expert / naïve 90% of doctors ‘turns’ are questions Negotiation of knowledge level

124

Is speaking to machines natural?

Turn taking Input / Feedback Turn taking cues

Asymmetrical partners Domain / World Knowledge Goals Language abilities Interpretation of ‘tokens’

125

Is speaking to machines natural?

Politeness You don’t say ‘please’ to a machine

Social Norms What happens when machine violates norms? Should synthesised speech sound human? What are the ‘norms’?

126

Back channelling from machines

MicroSoft Office Assistant

Process Control training simulation

Nodding ATM / TVM

127

Breakdown and Repair

Redundancy Shared knowledge / anticipation Focus signals

Given/new Deixis

Comprehension signals Communication signals

128

Eye contact and gaze

to convey interest signal comprehension and communication provide sense of engagement establish social presence

129

Video tunnel

monitor

camera

mirror

half-silvered mirror

130

7. Interaction Devices: Selecting Objects

131

Deixis

Pointing to things using

words and gestures:

“Please can I have that.”

“Please can I have that tart.”

“Please can I have that fruit tart.”

“Please can I have that strawberry tart.”

132

Deixis in HCI

Point Move cursor onto object Indicate object (highlighting)

Select Click button

Manipulate Click button

133

Select Object Step One: Indicate Object

Enter Objects Name or I.D. Type Write Speak

Position Selector on Object Direct: touchscreen, stylus, pen Indirect: cursor (using mouse, trackball, joystick)

Step Two: Confirm Selection Press key to confirm Press button to confirm Tap object to confirm

134

Device Models

Buxton’s 3-state device model

State0

State1

State2

135

Application

State0

State1

State2

Out of range

Pen on

Pen off Button up

Button down

select drag

136

Different pointing devices

Device State0 State1 State2

Touchscreen X

Pen X X X

Joystick X X

Mouse X X

137

8. Multimodal Human Computer Interaction

138

Divided Attention

Dual tasks require people to divide attention

Limited attentional resource that is shared between tasks

Depends on tasks, e.g., talk and drive, sight read music and shadow speech

139

Allport et al. (1972)

Participants presented with essay, either visual and auditory

Recognition test far worse with auditory 0

10

20

30

40

50

Pictures Visual

Words

Auditory

Words

Control

Experiment

Err

ors

in R

eco

gnit

ion (

%)

140

Task Similarity Interference when use same stimulus modality – visual or

auditory

Interference when use same stage of processing – input: central: output

Interference when use same memory codes – verbal or visual

Interference when use same response codes – spoken or manual

141

Practice and Expertise

Highly practised dual-task performance, e.g., 6 weeks read + take dictation

Expert pianists can sight-read + shadow; expert typists can touch-type + shadow

Performance strategies Reduced demand Reduced resource load

142

Contrasting Definitions

Technological Computers can present information using different

display modes and can receive information from different devices

Human Humans can receive information via different

senses and perform actions using different effectors

143

Modalities

Modality Refers to human sensory modalities

Sight Hearing Touch Smell , Taste

and response modalities Speech Manual

Multimodal system Supports HCI using more than one sensory and

response modality

144

Types of Multimodal System

Task

Goal

Dependent Independent

Independent Exclusive Concurrent

Dependent Alternate Synergistic

145

Exclusive

Separate tasks, each with their own goals Performance on tasks interact Example:

Surveillance system with camera control Enter data + control camera Data entry delayed by camera control

146

Alternate

Separate tasks with shared goals Performance on tasks interact Example:

Surveillance and target identification Control camera and zoom-in on targets Identify and report targets

147

Concurrent

Separate tasks, each with their own goals Tasks do not affect each other Example:

Target identification with vehicle control Identify targets + manoeuvre vehicle

148

Synergistic

Separate tasks with shared goal Tasks do not affect each other Example:

Mark distance on map ‘How far from here to here?’ Pen + speech

149

Put That There

Spoken commands

Manual gestures

Bolt (1980)

Put that red

triangle…

…there

150

IBM OpenSpace

151

QuickSet

152

Pointing and Speaking

People do not interact multimodally with multimodal interfaces

Speech and pointing is not dominant Around 20% of

conversation, and 14% of multimodal HCI

153

Sequencing and Timing

Not all actions are simultaneous

99% of pen + speech has pen actions first

154

Languages of Multimodal HCI

Speech: ‘place a boat dock on the east, no, the west end of Reward Lake’

Pen: [draws rectangle] ‘add dock’

155

Future Multimodal HCI

Development of future multimodal systems “…depends on knowledge of the natural integration patterns that typify people’s use of combined input modes.”

“The design of multimodal systems that blend modes synergistically depends on…”

properties of different modes the information they conveyhow multimodal input is synchronized

156

9. Future Human Computer Interaction

157

Weiser’s Scales of Interaction

Inch, foot, yard Tab, pad, board

158

Inch = Pad

ParcTAB PDA Individual many networkable

159

Foot = pad

Notebooks Tablet E-paper Individual several

160

Yard = board

Smartboards Plasma displays Control mimics Public sharable

161

Forms of interaction

Implicit interaction devices Sensors Awareness Recognition technologies Natural

Explicit interaction devices Keyboard, pointing

162

WIMP considered ‘fatal’?

Brad Rhodes The user has screen real-estate to burn

too much information on screen

The user has Fine motor control Eye-hand coordination

Digital information is a primary task

http://www.hitl.washington.edu/people/grof/VRAIS98/Rhodes.html

163

Wearable WIMP

Clear mapping between user action and goal Windows

Multiple views for multiple functions Icons

Presentation of graphical signs and symbols for prompts and commands

Menus Presentation of restricted option set

Pointing devices Object selection and manipulation

164

Windows on Wearables

Unclutter world Minimal information views Design display to augment world

Emergent features Design display to support pattern recognition

Integrate display Design display to interact with world

165

WIMP considered ‘fatal’?

Brad Rhodes The user has screen real-estate to burn

too much information on screen

The user has Fine motor control Eye-hand coordination

Digital information is a primary task

http://www.hitl.washington.edu/people/grof/VRAIS98/Rhodes.html

166

Wearable WIMP

Clear mapping between user action and goal Windows

Multiple views for multiple functions Icons

Presentation of graphical signs and symbols for prompts and commands

Menus Presentation of restricted option set

Pointing devices Object selection and manipulation

167

Windows on Wearables

Unclutter world Minimal information views Design display to augment world

Emergent features Design display to support pattern recognition

Integrate display Design display to interact with world

168

Icons on Wearables

Reduce text

Reduce information load

169

Text vs. Graphics

Baber et al., 1999, Mobile Networks and Applications 4

Mean Reaction Times

Graphical TextualHMD 1.45s 1.85sVDU 1.0s 1.5s

170

Menus on Wearables

Clarify options

Restrict activity

Access and enable through world activity

171

Emergent Properties

Baber et al., 1999, Interact’99

172

Limited Options

Bristow, WECAPC

173

Integrate with world

Baber et al., 2000, Interact’00

174

Pointing on Wearables

Selection on display

Selection in the world

175

Selection in the World

Baber et al., 2000, Interact’00

176

Selection from Display

Carnegie-Mellon Rotary dial selector

Accelerometer for simple gestures

Speech recognition

Bass et al., 1997, CHI’97

177

Augmenting the World

178

Digital Desk

Real paper on desk is scanned by a camera,

computer images are projected onto the paper

179

Graspable Objects

BUILD-IT Move blocks on

table

Change layout of room on displays

Fjeld 1999

180

GeoSPACE

Hiroshi Ishii – MIT

Physical objects to manipulate map display

181

Rekimoto’s InfoBoard

Pick and place objects using pen

Move objects between laptops or virtual storage

182

Data Storage

Data containers from Philips

183

Data tiles

Magnetic tiles linked to ‘data’

Projection labels tiles

184

Rekimoto’s Data Tiles

185

Haptic VR

Provide touch to virtual objects using force-feedback devices

186

Haptic Augmentation

Use real objects to control virtual representations

187

Handheld AR

PDA used to provide ‘views’ on world

Views change with PDA movement

188

Information Appliances

189

Domestic Appliances

Microprocessors in cars, dishwashers, washing machines, televisions etc.

Domestic appliances as ‘embedded systems’

190

Norman (1999)

Information Appliance:

“An appliance specializing in information: knowledge, facts, graphics, images, video, or sound. An information appliance is designed to perform a specific activity, such as music, photography, or writing. A distinguishing feature of information appliances is the ability to share information among themselves.”

D.A. Norman, 1999, The Invisible Computer, MIT Press, p. 53

191

Pervasive / Ubiquitous

Invisible Computer

Embedded Systems

Networks

192

Information Appliances

Digital camera: Capture image Immediate (shared) viewing of image Download image onto computer

Edit image Email image

193

Three Axioms

Design Axiom 1: Simplicity The complexity of the appliance is that of the task not

the tool. The technology is invisible.

Design Axiom 2: Versatility Appliances are designed to allow and encourage novel,

creative interaction

Design Axiom 3: Pleasurability (fun) Products should be pleasurable, fun, enjoyable. A joy to

use, a joy to own.

D.A. Norman, 1999, The Invisible Computer, MIT Press, p. 67

194

Current Trends

Device marriages digital camera + telephone PDA + telephone + MP3 + digital camera

Problems Visibility

Which device is currently ‘on’ Accessibility

How to switch devices / modes? Functionality

What functions are actually used?

195

11. Distributed Cognition

196

Using an Abacus for Addition

6 + 2 = 8

Heaven beads = 5 each

Earth beads = 1 each

8 + 2 = 10

197

Shopping Lists

Construct list Using the process of writing the list to support

decision making Remember to consult list

Check the list during shopping Use the list to help navigate the store

Reading and interpret list Make sure everything is bought

198

Shopping Lists

Memory aid Do we only buy what’s on the list? Do we buy items not on the list?

Additional tasks Does writing the list create a new task?

Modified task Does using the list change the way we shop?

199

‘Things that make us smart’

Cognitive Artefacts used to assist everyday activity Shopping List Knotted handkerchief Calculator Diary

200

Using Lists

Construct list Pre-computation [Hutchins]

Remember to consult list Checklists in inspection

Reading and interpret list Following checklists accurately

201

Cognitive Artefacts

Distribute actions across time Pre-computation

Distribute actions across actors Distributed cognition

Change actions required

202

Artefacts & Representation

Surface representation Display and maintenance of symbols on a

visible surface

Internal representation Storage and organisation of symbols

External representation

203

Mapping

Naturalness Related to directness of mapping Related to expertise / familiarity

Appropriateness Information should be appropriate to the task

(neither more nor less)

204

Distributed Cognition

Share knowledge and information across people, things, actions

Shopping lists

Ed Hutchins on calculating ships speed

E. Hutchins, 1990, The technology of team navigation, In Galegher et al. Intellectual Teamwork, LEA

205

Calculating Ships Speed

1. D=RT, (R=D/T) using pencil and paper

2. D=RT, using calculator

3. 3-minute rule: 3-minutes = 1/20 of an hour, and 100yds in 1/20 of a nautical mile

1500 yds in 3 minutes = 15nmph

206

Calculating Ships Speed

4. Nautical Slide Rule

207

Calculating Ships Speed

Knowledge-in-the-head [1] 2000 yds nautical mile 60 minutes in hour D=RT Transposition of equations

Knowledge-in-the-head [2] 3-minute rule: schema for shortcut

208

Calculating Ships Speed

Knowledge-in-the-World Nautical slide rule

Replace calculation with manipulation Colleagues

Draw upon experience of others Teamwork

Plotter Bearing taker Bearing timer-recorder

209

12. Collaborative Working

210

Traditional HCI

One User One Computer One Location One Task?

211

Limitations of this view…

Task focus on computer AND on other artefacts, e.g., paper, telephone, filing cabinet etc.

Other artefacts imply more than one location Office work often collaborative SO: computer only part of the work domain and is

not designed to fit with other parts

212

Personal Computers in the Office

1970s: development of the ‘desktop metaphor’ Objects on screen analogous to objects in world,

e.g., folders, files etc. Manipulation of objects on screen analogous to

manipulation of objects in world, e.g., open folders, put files into folders

BUT: no link between virtual and real objects

213

Changing HCI

Many Users Communication and Collaboration Multiple Access (WWW)

Many Computing Devices Embedded Systems PDAs, cell-phones and beyond

Many Locations Physical location (mobility) Virtual locations (WWW)

Many Tasks

214

Computer Mediated Communication (CMC)

Same place Different place

Same time

(synchronous)

Face-to-face Telephone

Different time

(asynchronous)

Post-in notes Letter

215

CMC

Synchronous Speech: telephone, videophone, videoconference Text: SMS, chatrooms, instant messaging

Asynchronous Speech: voicemail, answerphone Text: bulletin boards, newsgroups, computer conferencing

Mixed with other tasks Electronic Meeting Room

216

Shared Representations

Shared Calendars Access appointments diary to view or edit

(depending on privileges)

Shared Awareness

Shared Activities

217

Shared Awareness

Portholes: Xerox 1992

Low resolution images of people in their offices

Overhearing / overseeing

218

Shared Activities

Work on same text Add comments Restructure

Work on same drawing Modify Suggest alternatives

219

Collaborative Virtual Environments (CVEs)

Distributed VR systems

Individuals collaborate in virtual landscapes to share information and work together

220

CVEs

Meeting places Multiple representations Shared context

Shared knowledge, environment, tasks, objects Awareness of others Communication

221

Reading Virtual Control Room

Avatars

VirtualDisplayBoards

Augmented Displays

VirtualMonitors

ToVirtualPlant

222

Interaction in Virtual Space

With other actors

With virtual objects

With real objects?MagicBook project

223

Collaborating in real space

Technology to bring the virtual world to the real world

Shared representations on familiar surfaces

Surfaces to support interaction

224

RoomWareG

MD

-IPSI, W

iege, Wilkhahn

Source: Carroll, p. 569

ConnecTable

CommChair

InteracTable

DynaWall

225

Shared Awareness

Portholes: Xerox 1992

Low resolution images of people in their offices

Overhearing / overseeing

226

Exercise #.1

1. Apple 2. North 3. Charlie 4. Nickel 5. Red 6. Banana 7. South 8. Fred 9. Cent 10. Green 11. Pear 12. East 13. George 14. Dime 15. Yellow 16. Grape 17. Wayne 18. Dave 19. Penny 20. Blue

Make a note of the word numbers and enter into table

How many people wrote: West or Orange? What pattern do you notice in the words?

227

Exercise #.2

1. Latch 2. Bream 3. Hot 4. Mayor 5. Jab6. Busk 7. Else 8. Wage 9. Clog 10. Jowl 11. Chap 12. Big 13. Smug 14. Duck 15. Trout 16. Blot 17. Reek 18. Tape 19. List 20. Skirt

Make a note of the word numbers and enter into table

What pattern do you notice in the words? Did you do as well as with the first list?

228

Exercise #.3

1. Time 2. House 3. Mit 4. Stab 5. Solve6. Draft 7. Say 8. Off 9. Boil 10. Court 11. Greet 12. Slot 13. Hand 14. Dirt 15. Clot 16. Stale 17. Out 18. Dumped 19. Stone 20. Dice

• Make a note of the word numbers and enter into table

• Did you do as well as with the other lists?

top related