Univ.-Doz.Ing.Mag.Mag.Dr. Andreas HOLZINGER www ...user.medunigraz.at/andreas.holzinger/holzinger/papers en...Univ.-Doz.Ing.Mag.Mag.Dr. Andreas HOLZINGER Applying User-Centered Design

[email protected] Graz, 26.2.07

Univ.-Doz.Ing.Mag.Mag.Dr. Andreas HOLZINGER

www.basiswissen-multimedia.at

Applying User-Centered Design

706.046

Vorlesung-Übung (3 SE, 5 ECTS)

Interdisziplinäre Zusammenführung von Erkenntnissen aus Psychologie und Informatik zum

User-Centered Design und Development von Medienobjekten. [email protected]

Mo, 26.02.2007


Welcome

Our aim

Bridging the gap betweenPsychology and Computer Science

Psychology Informatics

Human-Computer Interaction


Hardware

Software Application

www.basiswissen-it.at


www.basiswissen-multimedia.at

Human ̶Computer

Human

Computer


Grading

Doing a project work in groups of 3 people and proceed in conference contribution style

Select a project ideaWork on the project togetherWrite a paper together (max. 3 authors)Submit to Committee (peer review)Presenting the paper in plenumDiscuss

How to get a (positive) gradingPart 1+2 (70 %): Project Presentation + Paper


Grading

Answering questions of UCD TheoryDichotomy YES/NO DecisionsMultiple ChoiceOpen Ended Questions

How to get a (positive) gradingPart 3 (30%): Written Examination


Technological Performance

Gordon E. Moore (1965, 1989, 1997)

Holzinger (2002), p. 69


Vast

redu

ctio

n in

cos

t, bu

t en

orm

ous

cap

abili

ty

Vgl. Moore (1965), Holzinger (2002), Scholtz & Consolvo (2004), Intel (2007)

.

Computer Cost/Size versus Performance


What is Performance?

Response time: the time between the start and completion of a task.Throughput: the total amount of work done in a given time.Some performance measures:

MIPS (million instructions per second)MFLOPS (million floating point operations per second), also GFLOPS, TFLOPS (1012), etc.SPEC (System Performance Evaluation Corporation) benchmarksSynthetic benchmarks


Small and Large Numbers

P

T

G

M

k

f

p

n

μ

m

yotta1024yocto10-24zetta1021zepto10-21exa1018atto10-18peta1015femto10-15tera1012pico10-12giga109nano10-9mega106micro10-6kilo103milli10-3

LargeSmall


Computer Memory Size

TBTbT1,099,511,627,776240

GBGbG1,073,741,824230

MBMbM1,048,576220

KBKbK1,024210

bytesbitsNumber


Components of Performance

Time period of clock (seconds, etc.)

Clock cycle time

Average number of clock cycles per instruction

CPI

Instructions executed by the program

Instruction count

Time (seconds, etc.)CPU time for a program

UnitsComponents of Performance


Units for Measuring Performance

Time in seconds (s), microseconds (μs), nanoseconds (ns), or picoseconds (ps).Clock cycle

Period of the hardware clockExample: one clock cycle means 1 nanosecond for a 1GHz clock frequency (or clock rate)CPU time = (CPU clock cycles)/(clock rate)

Cycles per instruction (CPI): average number of clock cycles used to execute a computer instruction.


Computer Performance

MetricsPopular measures

MIPS• Depends on inst. Set | Varies between progs

Can vary inversely with performanceGFLOPS• Better, perhaps, as instructions are similar• FLOPS can differ across machines


Top MachineBlueGene/L

first supercomputer in the Blue Gene projectSpecialised systems based on the Power architecture.

• Individual power 400 processors at 700Mhz

• Two processors reside in a single chip.• Two chips reside on a “compute card” with

512MB memory.• 16 of these compute cards are placed on a

node board.• 32 node boards fit into one cabinet, and

there are 64 cabinets.• 130,712 CPUs with theoretical peak of

183.5 TFLOPS/s• Multiple network topologies available,

which can be selected depending on the application.

High density of processors in a small area:• Low power and (comparatively) slow

processors - just lots of them!• Fast interconnects and low-latency.


Computer: Moore’s Law

MemorySpeed

PortabilityAffordabilityPerformance

1950 1990 2030

Computer "capabilities"

Moore (1997), and cf. Holzinger (2002), 69


Human versus Computer

Computers

Human Abilities

1950 1990 203010.000 BCAtkinson (1965), Hall (1988), Buxton (2001)


End-User in the Sixties (IBM 7030)

Bloch (1959), http://archive.computerhistory.org/stretch


Pictures removed


Difference?


How many "zeros" do you see?

3 1 4 1 5 9 2 6 5 3 5 8 9 7 9 3 2 3 8 4 6 2 6 4 3 3 8 3 2 7 9 5 0 2 8 8 4 1 9 7 1 6 9 3 9 9 3 7 5 1 0 5 8 2 0 9 7 4 9 4 4 5 9 2 3 0 7 8 1 6 4 0 6 2 8 6 2 0 8 9 9 8 6 2 8 0 3 4 8 2 5 3 4 2 1 1 7 0 6 7 9 8 2 1 4


How many red objects?

3 1 4 1 5 9 2 6 5 3 5 8 9 7 9 3 2 3 8 4 6 2 6 4 3 3 8 3 2 7 9 5 0 2 8 8 4 1 9 7 1 6 9 3 9 9 3 7 5 1 0 5 8 2 0 9 7 4 9 4 4 5 9 2 3 0 7 8 1 6 4 0 6 2 8 6 2 0 8 9 9 8 6 2 8 0 3 4 8 2 5 3 4 2 1 1 7 0 6 7 9 8 2 1 4

Bertin (1977), Card., Mackinlay & Shneiderman (1999), Holzinger (2001)


Fundamental Idea of a LO

Theory of atoms (Democrit, 400 B.C.)

Information Chunk (Miller, 1956)

OO-Theory (Dahl & Nygaard, 1966)

“…. a fundamental idea to create interoperable and reusable LEARNING OBJECTS.”

Reigeluth & Nelson (1997), Saddik et al. (2000), Holzinger (2001)


Learning is a basic cognitive & social process …not an object...

Knowledge

Proficiency

declarative

conceptual

skill

ability

Glasersfeld (1987), Knuth & Cunningham (1993), Holzinger (1997, 2000)

... it is an construction within every individual human memory.


Two different design approaches

Technology Centered DesignFeature driven:What can be realized on our platform?Tool driven: What can be created by using available tools?Interest Driven: What do the programmer find interesting?

Learner Centered DesignTask based:What do the learners really need?Ability based: What abilities/knowledge do the learners have?Domain based: In what context do the learners learn?

Norman & Draper (1986); Soloway, Guzdial, Hay (1994); Holzinger & Motschnig (2005)


Using Computers for learning purposes

Pedagogy Technology

extremely critical

"Replacement" for Teachers

"behavioristical" use only

social isolation

Examples: Neil Postman, Hartmut v. Hentig, …

uncritical, naive

euphorically

exaggerated expectations

Technology in foreground

Examples: Bill Gates, John Chambers, …

Baumgartner & Payr (1994), Holzinger (2000)


Research in e-Education on 3 Levels

Macro Level (Educational Systems and their framework and structures),Meso Level (Impact and comparison of institutional conditions) and onMicro Level (Research of technology enhanced educational processes)

Bronfenbrenner (1978, 81, 90)

Urie Bronfenbrenner (1917 – 25.Sept. 2005)


Attention!

Given the range of ways computers can represent feedback in a simulation, research is needed to ensure that design decisions are made based on the psychological needs of the individual end-user and not simply on what the computer is capable of doing!


Reading:A 34. Holzinger A. (2005): Usability Engineering for Software Developers. Communications of the ACM (CACM), 2005, Vol 48, Issue 1, 71-74A 25. Holzinger, A. (2004): Application of Rapid Prototyping to the User Interface Development for a Virtual Medical Campus. IEEE Software. Vol. 21, Iss. 1, January 2004, 92-99.


What is Usability?

Social acceptability Practical acceptability

Reliability Compatibility AffordabilityUsefulness

UtilityUsability

Learnability

Efficiency Memorability Errors

Satisfaction

System acceptability

[email protected] Graz, 26.2.07Buxton (2001), Marcus (2004)

Complexity! Technical knowledge required, regular software installation, updates & maintenance, usability of hardware, software & manuals, loads of unwanted features, crashes, ...

Ζ∈≥= fff

nnn

u ,11

Complexity as a barrier …


Definition of Usability

Dimension Description, e.g. … Benchmark

(1) LEARNABILITY

(2) EFFICIENCY

(3) MEMORABILITY

(4) FAULT-TOLERABILITY

(5) SATISFACTION

Low start-up overhead …

Easy to remember …

Time to repeat task

Time to perform task

Nielsen (1993), Nielsen & Levy (1994), Nielsen (1996)

Achieving high productivity …

Easy to recover from errors …

Measuring task performance

Numberof errors

Pleasant to use … Users subjective opinion


Metrics ISO 9241, ISO 13407

Objective Effectiveness Efficiency Satisfaction

Suitability % of goalsachieved

Time toComplete

SubjectiveRating

Appro-priateness

# of powerfeatures used

Relative toexpert

Rating ofpower

Learnability % learned Time tolearn

Rating oflearning

Error % errorscorrected

Time tocorrect

Rating oferror handling

Dix et al. (1998), ISO 9241, ISO 13407


1977: Release of Apple II with graphical interface1985: Gould and Lewis promote User-centered Design1988: Norman and Draper, User-centered System Design[1990’s] –

Interest in field methods, Rapid increases in computing power and options, Emergence of prototyping tools, Global marketplace, Internet…

1999: ISO standards for human-centered design2001: FIRST Special issue IJHCI, Human-centered design


Usability is the typical way a product is evaluated

Usability Engineering (UE) is all encompassing to enable good Usability

User-centered design (UCD) is one approach of UE to incorporate the end-user in design and development (User-centered development)


Standard ISO HCI (1)

1Design for quality in useISO 9241-11, ISO 9126-4: effectiveness, efficiency, (safety), satisfactionISO 20282-2 Usability of everyday products

2Design the user interfaceISO 9241 parts 12 to 17 Ergonomic principles

3Use user-centred methods in developmentISO 13407 Human centred design processes

4Establish organisational processesISO TR 18529 Human-centred lifecycle process descriptions


Standard ISO HCI (2)

process quality product quality quality in use

usability in context

development process

product effect of the product

user centred process

interface and interaction

ISO 13407 ISO 9241-11ISO 14598-1

ISO/IEC 9126-1ISO/IEC 9126-4

ISO 20282-2

organisational capability

life cycle processes

usability capability

ISOTR 18529 ISO 9241 parts 10, 12-17ISO/IEC 9126-2/3


User-Centered Design

Other standards:ISO 10741

• cursor control in text systemsISO 11581

• appropriate icon symbols and functionsISO 13407

• user-centered design for interactive systemsISO 14754

• basic gesture commands for text editingetc.


Again: How usability is defined: Items in four different usabilityconstructs

•Understandability•Learnability•Operability•Attractiveness

“The capability of the software product to be understood, learned, used and attractive to the user, when used under specified conditions.”

•Effectiveness•Efficiency•Satisfaction

"The extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use."

•Learnability•Memorability•Efficiency•Subjective satisfaction•Low rate of errors

•Effectiveness:performance in accomplishment of tasks and the access to potential utility.•Learnability:degree of learning needed to accomplish tasks.•Flexibility:adaptation to variation in tasks.•Attitude: user satisfaction with system.

ISO 9126-1 (2000)

ISO 9241-11(1998)

Nielsen (1993)Shackel (1986)


UCDev, Marcus (2002), Holzinger (2003)

Requirements > User Analysis > Task Analysis > Lo-Fi Prototype > Evaluation > Reengineering > Prototype > Evaluation > Reengineering

cf. Boehm (1988)


Holzinger (2004)


Audience Analysis

“Know thy end-users”

Common dimensions includeRole – Dominant persona of users (job, affiliation)Goals – Reason for the interactionCircumstances of Use – Setting, resources, strategy, timing Culture – Group level beliefs, language, preferencesErgonomics – Relevant perceptual & motor abilities, skills


User Centered Design

Know thy end-users!Cognitive abilitiesPhysical abilitiesMotivational backgroundPrevious knowledge and skills!

Keep users involved throughout the development process …


Ergonomics (examples)

Physical ergonomics human anatomical, anthropometric, physiological and biomechanical characteristics as they relate to physical activity::

postures, materials handling, repetitive movements, work relatedmusculoskeletal disorders, workplace layout, safety and health.

Cognitive Ergonomics mental processes:perception, memory, reasoning, and responses:

mental workload, decision-making, skilled performance, human-computer interaction, human reliability, work stress and training.

Social Ergonomics implies to consider more than one person and information technology is made for people to communicate and to work together CSCW (computer supported collaborative work)

communication, resource management, teamwork, participatory design, cooperative work.


Organizational goal

Eason’s Socio-technical systems: Levels of analysis

OrganizationalgoalSocial system

Technicalsystem

Work

People Technology

LEVEL 3 Society

LEVEL 2Organization

LEVEL 1Individual

Eason (1991)


Methods used

cf. Nielsen (1994), Andrews (2002), Holzinger (2003), Holzinger (2005)


Nielsen's famous findings

problems found benefits / cost

cf. Nielsen (1994)


Field studiesEvaluatereal life

PaperMock-up

Thinking aloud

Usability testing

Low-fiDesign

Prototype

Thinking aloud

Usabilitytesting

Hi-fi Design

Implement

User studies, function tests

Evaluate

Develop

Identification of end-users

Specs

Contextualinquiry

Analysis

TaskAnalysis

Objectives

Holzinger (2004), Holzinger (2005)

User Centered Development (UCD)


Low-Fi – High Fi Prototyping


Thinking Aloud Protocol

Subjective –but one of the most valuable methods in usability engineering!Literally, the user "thinks aloud" whilst going through tasks and their thoughts are recorded.Designers can then see what the user was thinking at the time of having problems.Reveals not only what the problems are, but why!


Understand Humans

Understand perceptual system to understand how we perceive information and response timesUnderstand cognitive system to understand how we learn, remember, and make decisionsUnderstand motor system to understand limits of human task performanceUse knowledge to inform the design of interfaces


Lomax, H and Casey,N. (1998) ‘recording social life: reflexivity and video methodology’, sociological research online, 3(2) http://www.socresonline.org.uk/socresonline/3/2/1.htmlRose, G. (2001) Visual methodologies: an introduction to interpreting visual objects. London: Sage.Van Leeuwen, T. and Jewitt, C. (2000) The handbook of visual analysis. London: Sage. (in particular Goodwins chapter 'Professional vision')Pink, S. (2001) Doing visual ethnography: images, media, and representation in research. London: Sage.Banks,M. (2001) Visual methods in social research. London: Sage.Banks, M and Morphy, H (Eds) (1997) Rethinking Visual Anthropology, New Haven: Yale University Press.Prosser, J (Ed.) (1998) Image-based Research: A Sourcebook for Qualitative Researchers, London: Falmer Press.Emmison, M. and Smith, P. (2000) Researching the visual. London: Sage.Norris, S. (2004) Analyzing Multimodal Interaction, London: RoutledgeFalmer.R.Flueitt (2005 – October) Using video to investigate preschool classroom ineraction, Visual Communication 4(3).

Some resources on Video Analysis


Interactions: New Visions of Human-Computer Interaction, Vol. 12, Issue 3, 64


Again …

Richard E. Clark (1994)“Technology is the answer, but what is the question?”Today, the technology has changed … but the question has not!


How usability is defined: Items in four different usability constructs

•Understandability•Learnability•Operability•Attractiveness

“The capability of the software product to be understood, learned, used and attractive to the user, when used under specified conditions.”

•Effectiveness•Efficiency•Satisfaction

"The extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use."

•Learnability•Memorability•Efficiency•Subjective satisfaction•Low rate of errors

•Effectiveness:performance in accomplishment of tasks and the access to potential utility.•Learnability:degree of learning needed to accomplish tasks.•Flexibility:adaptation to variation in tasks.•Attitude: user satisfaction with system.

ISO 9126-1 (2000)

ISO 9241-11(1998)

Nielsen (1993)Shackel (1986)


HCI ISO overview

process quality product quality quality in use

usability in context

development process

product effect of the product

user centred process

interface and interaction

ISO 13407 ISO 9241-11ISO 14598-1

ISO/IEC 9126-1ISO/IEC 9126-4

ISO 20282-2

organisational capability

life cycle processes

usability capability

ISOTR 18529 ISO 9241 parts 10, 12-17ISO/IEC 9126-2/3


Learning requires cognitive effort!

Successful learning results in permanent understanding of contexts and

in mastering problems (zone of developments) –not just fun of edutainment!

Lessons Learned

Shall we make learning as easy as possible?

Wilhelm Busch (1832-1908)


Future Research

We need much more research to help define the learning goals that best profit from new technologies … in real-life …

Richard E. Mayer (2005)


Human-Computer Interaction (HCI) & Usability Engineering (UE) is integrating

HCI&UE and the power of M3

Media Psychology

Media InformaticsMedia Education

Design & Development

Holzinger (2002, 2003, 2004, 2005), Holzinger & Motschnig (2005)

Documents

Univ.-Doz.Ing.Mag.Mag.Dr. Andreas HOLZINGER www ...user.medunigraz.at/andreas.holzinger/holzinger/papers en...Univ.-Doz.Ing.Mag.Mag.Dr. Andreas HOLZINGER Applying User-Centered Design