Human Computer Interaction

Transcription

1 Dr Mark Wright - Informatics HCI Course 2012/13 Human Computer Interaction Dr Mark Wright University of Edinburgh and Edinburgh College of Art Semester /2013

2 Principles and Overview Lecture 1 Key points: Definition The Three Paradigms of HCI The Technological Background What knowledge does HCI have to make good interactions? When is this knowledge relevant and how do you apply it? Dr Mark Wright - Informatics HCI Course 2012/13 1

3 Definition of HCI "Human-computer interaction is a discipline concerned with the design, evaluation and implementation of interactive computing systems for human use and with the study of major phenomena surrounding them." Association for Computing Machinery

4 The 3 Paradigms of HCI Human Factors Engineering Epoc Classical Cognitive Information Epoc The Three Paradigms of HCI Harrison, Tatar and Sengers CHI 2007 Embodied/Situated Interaction Epoc 4

5 The 3 Paradigms of HCI Awareness of the paradigms help us make sense of this huge field 1st HCI Paradigm Human Factors Engineering Epoc 2nd HCI Paradigm Classical Cognitivism Information Epoc 3rd HCI Paradigm Embodied Cognition Interaction Epoc Metaphor of Interaction Interaction as Man- Machine Coupling Interaction as Information Transfer Interaction as Phenomenologically Situated Central Goal for Interaction Optimise fit between man and machine Optimise accuracy and Efficiency of Information Transfer Support of Situation Action in the World Typical Questions of Interest How can we fix specific problems that arise in Interaction? What mismatches arise in communication between humans and computers? How can we accurately model what people do? How can improve the efficiency of HCI? What existing situated activities should we support? How do users appropriate technology? How can we support interaction with constraining it by what a computer can do/understand? What is the wider context roles, politics and values?

6 The 3 Paradigms of HCI Today Paradigms 2&3 Largely Predominate Appropriate Disciplines for Interaction Desirable Methodologies Legitimate kinds of Knowledge 1st HCI Paradigm Human Factors Engineering Epoc Engineering, Programming, Ergonomics Cool Hacks Pragmatic Objective Details 2nd HCI Paradigm Classical Cognitivism Information Epoc Laboratory and Theoretical Behavioural Science Verifiable Quantitative design and evaluation methods that can be applied regardless of context Objective facts and models with general applicability 3rd HCI Paradigm Embodied Cognition Interaction Epoc Ethnography, Action Research Ethnomethodology, Interaction Design, User Centred Design A palette of situated design and evaluation strategies Thick Description of Context and Stakeholder Concerns. How do you know something is True? You Tried it out and it worked You confirm of refute your hypothesis based on a statistical analysis of the evidence You argue about the relationship between your data and what you seek to understand

7 The 3 Paradigms of HCI Viewpoints: Paradigm2 Analytic/Scientific Paradigm3:Phenomenological/Design 1st HCI Paradigm Human Factors Engineering Epoc 2nd HCI Paradigm Classical Cognitivism Information Epoc 3rd HCI Paradigm Embodied Cognition Interaction Epoc Values Reduce errors and make it work. Ad Hoc is OK. Cool Hacks that exploit a specific instance are desired Optimisation. Strive for Objective, Abstract, Quantitative, Generalizable Knowledge wherever possible. Principled evaluation is a priori better than ad hoc, since design can be structured to suite this paradigm. Structured Design better than unstructured. Reduce Ambiguity. Top Down View of Knowledge. Construction of meaning is intrinsic to and unfolds from interaction. What goes on around systems is more interesting than what s happening at the interface. Zensign - what you don t build is as important and what you do build. Goal is to grapple with the full complexity around the system.knowledge can not just be a powerful abstraction but can be embedded in the world as hidden context and tacit skill which is revealed through engagement

8 Which HCI Paradigm is the correct one? Classical Cognitive Information Epoc Embodied/Situated Interaction Epoc The key question is not which of the paradigms is correct but what different perspectives, strengths, weaknesses, insights and tools they offer and when they are appropriate to apply 8

9 Technological Context HCI arose and evolved as Computer Technology arose and evolved. There are a number of recognisable eras and approaches associated with technologies which are useful to keep in mind One perspective is PreDesktop,Desktop and Post-Desktop Before HCI Physical Switches Teletype Terminals Early language development from machine code can be seen as an attempt to make programming easier. 9

10 The First WIMP Interface: Small Talk Xerox Parc First Computer Mouse 10

11 Wimp Interface - A relatively stable design - till recently? WIMP - Windows, Icons, Menus and Pointer The WIMP interface has remained relatively unchanged during a great deal of rapid development in technology, platforms and interaction metaphors. 11

12 Pre Internet - Stand Alone PC PC with little or no local network. No Internet Single Users on single machines using stand alone applications Spreadsheets were a huge early success of HCI 12

13 Web Static Web Static Web Pages Server Creates Browser Only Reads Slow Internet Few Content Creators No E-Commerce The age of web usability layout, colour 13

14 Web Dynamic Web Dynamic Web Client Side - Javascript Server Side Databases - PHP/ mysql Mashups - api s, Browser rather than OS based ecosystems Users as Content Creators Rich Internet Applictions (RIA) with the interactive experience of stand alone applications Typical Google Maps Mashup App for London Flats/Prices 14

15 Mobile and Social Media Smart Phones Apps vs HTML5 Location Based Services (LBS) Communication and Content Creation A post PC era of phones and tablets? Constantly changing interactions, social context and place. Twitter, Facebook, Foursquare, Google Maps

16 Social Computing CSCW Computer Supported Collaborative Working Beyond immediate interaction to a web of surrounding relations Ethnography, Ethnomethodology Actual Practices 16

17 Virtual and Augmented Reality Virtual Worlds - Simulation, immersion Second Life, Massive Multi-player Online Role Playing Games MMORPG Virtual Reality - A separate virtual place HeadMounted Displays, Caves Augmented Reality - The Real World Plus Tablets, Phones, Google Glasses 17

18 Ubiquitous Computing UbiComp Computers omni-present but invisible Computers escape from the desktop and disappear Wireless, Wearable, Small, Embedded RFID tags, Micro-controllers, Speckled computing, Machine to Machine Internet of Things IOT 18

19 Tangible Computing Physical Interface Use of Embodied skills Rich tactile and proprioceptive feedback Physical affordances and constraints of the physical world Tangible Bits: Towards Seamless Interfaces Between People, Bits and Atoms Ishii and Ullmer, CHI 97 19

20 What can we take from HCI to make better interactions? Science (Classical Cognitive Science) Theory and Models Formal Methods Experimental Method Statistical Inference Justification for laws and guidelines BUT as the Interface can change some knowledge is only speculative Embodiment and Situated Cognition suggest Ethnomethodology and Design are viable and useful methodologies too Social Context and Embedded knowledge are crucial but often hidden 20

21 Interaction Design Cycle 21

22 Design Rules for HCI n n n n Many sets of rules have been proposed to encapsulate understanding and best practice Operate at various levels principles abstract design rules an interface should be easy to navigate guidelines advice on how to achieve principle may conflict; understanding theory helps resolve use colour to highlight links standards specific rules, measurable MondoDesktop links are RGB #1010D0 23

23 Design Rules for HCI - standard 24

24 Design Rules Shneiderman s 8 Golden Rules (1987): 1. Strive for consistency 2. Enable frequent users to use shortcuts 3. Offer informative feedback 4. Design dialogs to yield closure 5. Offer error prevention and simple error handling 6. Permit easy reversal of actions 7. Support internal locus of control 8. Reduce short-term memory load 25

25 Design Rules Norman s 7 Principles (1988): 1. Use both knowledge in the world and knowledge in the head. 2. Simplify the structure of tasks. 3. Make things visible. 4. Get the mappings right. 5. Exploit the power of constraints, both natural and artificial. 6. Design for error. 7. When all else fails, standardize. 26

26 Design Rules Nielsen s 10 Usability Heuristics (1994): 1. Visibility of system status 2. Match between system and the real world 3. User control and freedom 4. Consistency and standards 5. Help users recognize, diagnose and recover from errors 6. Error prevention 7. Recognition rather than recall 8. Flexibility and efficiency of use 9. Aesthetic and minimalist design 10. Help and documentation heuristic_list.html 27

27 Consolidate the three lists here. Mark any you don t understand with * 28

28 Design Rules Dix groups these and related principles as follows: n n n Learnability the ease with which new users can begin effective interaction and achieve maximal performance (e.g. familiarity, generalisability, predictability) Flexibility the multiplicity of ways the user and system exchange information (e.g. customisability, substitutability, user control) Robustness the level of support provided to the user in determining successful achievement and assessment of goal-directed behaviour (e.g. observability, recoverability) 29

29 n n n n n n n Design Rules Many seem like common sense - but often violated Home exercise: pick one everyday object and one piece of software and assess with respect to these rules Some are grounded in our understanding of how humans perceive, think and learn Some are the result of empirical study (e.g. Nielsen s heuristics are based on factor analysis of 249 usability problems) Some are derived from particular characterisations of the nature of human action (e.g. Norman s principles are closely related to his theory of action) Some are collections of experience (e.g. Shneiderman s rules) Some can be directly related to computational complexity In this course we will study the background and justification of these rules and elaborate on how they can be applied in specific contexts to

30 Guidelines for various platforms Mac OS X Human Interface Guidelines: Grouping Items in Menus Arranging menu items in logical groups makes it easy for users to quickly locate commands for related tasks. The guidelines in this section can help you list menu items in ways that make sense to users. 30

31 When is this knowledge relevant and how do you apply it? HCI is a Research Discipline and a Design Practice HCI Research Goal is to gain insight whereas the practice is to make good interfaces. Quantitative and Qualitative approaches are useful for both. Need to judge if an issue is objective or subjective. Science it good at telling if a phenomenon is real or provide useful insight as to why an approach works. User Centred Design, Interaction Design, Scenarios, Prototyping are typical approaches of actual practice to uncover the complex issues which contribute to the creation of successful digital interactions in the real world 31

32 HCI Course Objective The aim of this course it to give you the grounding necessary to understand the Principles and Practice of HCI and how to use that knowledge to create better interactions between people and digital systems. 32

33 Key Texts 33