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Understanding Experience in Interactive Systems

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Understanding Experience in Interactive Systems

MODELS OF INTERACTION

terms of interaction

Norman model

Some terms of interaction

domain – the area of work under studye.g. graphics design

goal – what you want to achievee.g. create a solid red triangle

task – how you go about doing it– ultimately in terms of operations or actions

e.g. … select fill tool, click over triangle

Note … traditional interaction … use of terms differs a lot especially task/goal !!!

Donald Norman’s model

Seven stages user establishes the goal formulates intention specifies actions at interface executes action perceives system state interprets system state evaluates system state with respect to goal

Norman’s model concentrates on user’s view of the interface

execution/evaluation loop

user establishes the goal formulates intention specifies actions at interface executes action perceives system state interprets system state evaluates system state with respect to goal

system

evaluationexecution

goal

execution/evaluation loop

user establishes the goal formulates intention specifies actions at interface executes action perceives system state interprets system state evaluates system state with respect to goal

system

evaluationexecution

goal

execution/evaluation loop

user establishes the goal formulates intention specifies actions at interface executes action perceives system state interprets system state evaluates system state with respect to goal

system

evaluationexecution

goal

execution/evaluation loop

user establishes the goal formulates intention specifies actions at interface executes action perceives system state interprets system state evaluates system state with respect to goal

system

evaluationexecution

goal

Using Norman’s model

Some systems are harder to use than others

Gulf of Executionuser’s formulation of actions

≠ actions allowed by the system

Gulf of Evaluationuser’s expectation of changed system state

≠ actual presentation of this state

Human error - slips and mistakes

slip understand system and goal correct formulation of action incorrect action

mistake may not even have right goal!

Fixing things?slip – better interface designmistake – better understanding of system

INTERACTION STYLE

dialogue … computer and user

distinct styles of interaction

Common interaction styles

command line interface menus natural language question/answer and query dialogue form-fills and spreadsheets WIMP point and click three–dimensional interfaces

Command line interface

Way of expressing instructions to the computer directly function keys, single characters, short

abbreviations, whole words, or a combination

suitable for repetitive tasks better for expert users than novices offers direct access to system functionality command names/abbreviations should be

meaningful!

Typical example: the Unix system

Menus

Set of options displayed on the screen Options visible

less recall - easier to use rely on recognition so names should be

meaningful Selection by:

numbers, letters, arrow keys, mouse combination (e.g. mouse plus accelerators)

Often options hierarchically grouped sensible grouping is needed

Restricted form of full WIMP system

Natural language

Familiar to user speech recognition or typed natural

language Problems

vague ambiguous hard to do well!

Solutions try to understand a subset pick on key words

Query interfaces

Question/answer interfaces user led through interaction via series of

questions suitable for novice users but restricted

functionality often used in information systems

Query languages (e.g. SQL) used to retrieve information from database requires understanding of database structure and

language syntax, hence requires some expertise

Form-fills

Primarily for data entry or data retrieval Screen like paper form. Data put in relevant place Requires

good design obvious correction

facilities

Spreadsheets

first spreadsheet VISICALC, followed by Lotus 1-2-3MS Excel most common today

sophisticated variation of form-filling. grid of cells contain a value or a formula formula can involve values of other cells

e.g. sum of all cells in this column user can enter and alter data spreadsheet

maintains consistency

WIMP Interface

Windows Icons Menus Pointers

… or windows, icons, mice, and pull-down menus!

default style for majority of interactive computer systems, especially PCs and desktop machines

Point and click interfaces

used in .. multimedia web browsers hypertext

just click something! icons, text links or location on map

minimal typing

Three dimensional interfaces

virtual reality ‘ordinary’ window systems

highlighting visual affordance indiscriminate use

just confusing!

3D workspaces use for extra virtual space light and occlusion give depth distance effects

flat buttons …

… or sculptured

click me!

THREE LEVELS OF DESIGN

visceral | behavioural | reflective

THREE LEVELS of design

Play part in shaping one’s experience

Important

Require a different approach by the designer

visceral | behavioural | reflective

VISCERAL DESIGN

visceral | behavioural | reflective

QUOTE visceral design

“ Package designers and brand managers are looking beyond graphic elements or even the design as a whole to forge an emotional link between consumers and brands ”

The entire success of a product PACKAGE, not content

BOTTLE OF WATER

VISCERAL DESIGN what?

Is what nature does

Powerful emotional signals from the environment are automatically interpreted at this level

Culturally

Perception of “pretty”

Visceral design is all about emotional impact

LOOKFEEL

SOUNDD

OM

INA

TIN

G FA

CT

OR

S

DOMINATING FACTORS

Physical features

LOOK

FEEL

SOUND

These principles are wired in, consistent across people and cultures

VISCERAL DESIGN where?

Advertising

Folk

Crafts

Children items

VISCERAL DESIGN: how?

About initial reactions

Studied Putting people in front of a design Waiting for reactions

What is the reaction the visceral designer strives for?

I want it What does it do? How much does it cost?

BEHAVIOURAL DESIGN

visceral | behavioural | reflective

BEHAVIOURAL DESIGN

“Use and performance”

Four components

1. Function

2. Understandability

3. Usability

4. Physical feel

FUNCTIONB

EH

AV

IOU

RA

L D

ES

IGN

FUNCTION

Comes first

Product To fulfil needs

Tricky

TRICKY

Question: what does a product do, what function does it perform? Answer: it has to fulfil needs

Difficult: why ? People’s needs are not as obvious as might be

thought

Importance for designers

Designers have to watch their customers

to understand how they will use a product

PRODUCT DEVELOPMENT

Enhancement = making an existing product or service better Easiest: comes primarily by watching how people

use what exists today

Innovation = completely new way of doing something that

was not possible before Difficult to access: cannot be evaluated by asking

potential customers for their views

CAR CUPHOLDERS

UNDER-STANDINGB

EH

AV

IOU

RA

L D

ES

IGN ?

UNDERSTANDING

The secret

= to establish a proper conceptual model Three mental images

1. Designer’s model

2. User’s model

3. System image

= conveyed by the product and written material (advertising and manuals)

The system image of the final design conveys the proper user model

FEEDBACK

“Component of understanding”

To give continual feedback

Computer

Amazing: many products give inadequate feedback

To be effective? Enhance the conceptual model Indicating precisely

What is happening and what remains to be done?

USABILITYB

EH

AV

IOU

RA

L D

ES

IGN

USABILITY

Complex topic

“a product that does what is required and is understandable, may still not be usable”

E.g. guitars, violins, piano

Usage = the critical test of a product: How well does the product perform? How comfortable does it feel to use?

Challenge = UNIVERSAL DESIGN

PHYSICAL FEEL

BE

HA

VIO

UR

AL

DE

SIG

N

PHYSICAL FEEL matters

Designers worry a lot about the physical feel of their products

Make huge difference in our appreciations

They are critical to our behavioural assessment of a product

Physical feel matters: why? We are biological creatures: interaction between

our sensory systems and the environment

+ BEHAVIOURAL DESIGN +

Human-centered

Understanding and satisfying the needs Observation

Visceral and behavioural reactions are subconscious Make us unaware of our true reactions and their

causes

REFLECTIVE DESIGN

visceral | behavioural | reflective

REFLECTIVE DESIGN what?

Message, culture, meaning of a product

The image we present to others

The essence of reflective design: it’s all in the mind of the beholder

QUESTION function vs fashion

ATTRACTIVENESS <> BEAUTY

Attractiveness Visceral level

The response is entirely to the surface look of an object

Beauty Reflective level

It is influenced by knowledge, learning and culture

Advertising

can work at either the visceral or the reflective level

REFLECTIVE LEVEL product

Shows person’s overall impression

Customer relationships play a major role A good relationship reverse a negative

experience

Is about long-term customer experience Service Providing a personal touch Warm interaction

CONCLUSION

A human-centered approach works well for behavioural design, but it is not necessarily appropriate for either the

visceral or the reflective side

Conclusion If you want a successful product, test and revise If you want a product that can change the world:

let it be driven by someone with a clear vision