User Interfaces 4

BTECH: ITWIKI PAGE:

https://userinterfaces4.wikispace.com

What is HCI• Human Computer Interaction• Usability• Useful vs Usable• Usability in existing systems

Examples of interactive systems

• ATM’s• Cell phones• Video Recorders• Websites• Computer Applications

Usability• Useful: the system supports user objectives• Usable: it supports user objectives in easy-

to-use ways• Accessible: it can be used by the full range

of intended users

“Every designer wants to build a high-quality interactive system that is admired by colleagues, celebrated by users, circulated widely, and imitated frequently. “ (Shneiderman, 1998)

ExeciseEvaluate each of the following in terms of usefulness, usability and accessibility, motivating your answer with an example:• Finding your lectures and venues• Finding out online whether a

particular movie is showing and the show times

• Ordering pizza by phone

Natural Computing• Humans are capable of processing

information

• Three linked aspects:o User: user as focus, user modellingo Designer: understand human information

processing, understand intended userso Sustainability: support activities to

achieve objectives

User-centred Design (UCD)

• Target users (preferences and requirements)

• Simple models of users, tasks and technological systems

• Interactive process• Prototyping and evaluation of alternatives

by users

The old computing is what computers can do, the new computing is what users can do (Shneiderman, 2002)

Examples

Designer I nterface

User 1

User 2

Design from 1st Principles

Designing by copying

What is beautiful?

Principles of natural computing

• Natural computing• What users can do• Modelling users• Understanding the domain• Understanding human learning• Meaning as a basis for practical learning

Natural computing• People and technologies work with symbols• Sciences involved: cognitive science,

cognitive psychology, human-computer interaction, interaction design, sociology and anthropology

What users can do• Target users• Frequency of use: novices, casual users,

regular• Application knowledge: experts, operators• Tasks to be performed: use part of a

system, decisions based on data from transactions, maintenance of system

• Assumed skills: skills acquired independently of particular application

• Attitudes: regard software as a challenge, conservative, preferred modes of interaction

Modelling users• A working model of human,

natural computation• Simplex Theory:

oTheory to guide good practice design

oFramework to capture current research findings

(Simple enough to guide best practice and complex enough to encompass current research issues)

Understanding the domain

• “Domain”of the system, e.g. accounting, medical, POS, etc.

• Wide range of disciplines• Use experts in domain to id understanding

Understanding human learning

• Psychology: how information is processed• Cognitive psychology: Theories of human

perception

Meaning as a basis for practical learning

• Not just a set of rules to be applied • Context important• People important• Link between theory and practice to

encourage better understanding

EXERCISE• Research and write a short paragraph

on one of the following, referencing appropriately, and paste it to the wiki page using your student number:oVon Neumann machinesoFuzzy logicoAdaptive and adaptable systemsoFault tolerant and self-repairing

systems

Core concepts• User Model• Universal access• Design for all• Inclusive design• Task Models• Technological platform

Exercise• Find definitions/descriptions for all

the “core concepts