Presentation on theme: "What is HCI and where does GUI design fit in?"— Presentation transcript:
1What is HCI and where does GUI design fit in? Lecture 1 CSE3030
2Outcomes of the lecture Be able to describe the field of HCIBe able to argue whether or not specific subjects should fall within the fieldUnderstand how the design of graphical interfaces fit within the broader field of HCI
3HCI definedHuman-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 themThis is a ‘working definition’From the ACM SIGCHI (Association of Computing Machinery, Special Interest Group for Human-Computer Interaction)
4What is and isn’t HCI?On the H side?On the C side?
9Beyond intuitionHuman-machine system designers cannot just rely on intuition – too many complex factors are operating.Instead, need to look to:High level theories/models/principlesMiddle level principlesSpecific & practical guidelinesIntuition – that looks good or right to me is not an adequate design criteriaHigh level theories – human factorsMiddle level - specific computer interfaceLow level – guidelines for types of computer applications - egstyle guides for a particular look and feel,widget-level guidelines
10HCI principlesGeneral design principles involve being aware of, and catering to, human abilities, skills and differences (human factors). These apply to design of any human-machine system e.g. cars, playgrounds, lifts, phones, computers.Designing human-computer interaction is a particular area of human factors design with specific principles and guidelines.Designing user interfaces is specific area of HCI and concerns general principles & low level concerns.High level theories – human factorsMiddle level – specific computer interfaceLow level – guidelines for types of computer applications - egstyle guides for a particular look and feel,widget-level guidelines
11HCI: Three basic principles People want ease of use – usually provided by simplicity and transfer of existing experience.The user view is different to the system engineers view. Often engineers design systems to perform a set of functions rather than with the user in mind.Computers and people are both better at some tasks than others – however they are better at different tasks.E.g. we see a word spelt jomp our brain says its probably meant be jump but a computer is totally literal.See sh p. 84.
12Human factorsInvention of machines (cars, airplanes, electronic devices ...) taxed people’s sensorimotor abilities to control them.Even after high degree of training, frequent errors (often fatal) occurred.Result: human factors became critically important.
13Human factorsHowever, designers still often consider cost and appearance over human factors design.People tend to blame themselves when errors occur:“I was never very good with machines”“I knew I should have read the manual!”“Look at what I did! Do I feel stupid!”Bad design not always visible, but sometimes it is very obvious!
14Human factors How many of you can program or use all aspects of your: digital watch? Fax machines?VCR?stereo system (especially car stereos)unfamiliar water taps?“..no need to understand the underlying physics ..(or code) of everything …simply the relationship between the controls and the outcomes” - Donald Norman – “The design of everyday things”Technology is getting more complicated.Different taps.
15Related Fields Computer science Psychology Sociology and anthropology application design and engineering of human interfacesPsychologythe application of theories of cognitive processes and the empirical analysis of user behaviorSociology and anthropologyinteractions between technology, work, and organizationIndustrial designinteractive products
16Design processImportant to consider the What, Why and How of design process for an application before you even begin to think about the interface, coding, etc.User needs and usability goals must be addressed at the beginning of the design process. Designers can make incorrect assumptions about the requirements.Designers are really often not in tune with the users needs - even their basic requirements and situations
17WAP mobile phone example People want to be kept informed of up-to-date news wherever they are - reasonablePeople want to interact with information on the move - reasonablePeople are happy using a very small display and using an extremely restricted interface - unreasonablePeople will be happy doing things on a cell phone that they normally do on their PCs (e.g. surf the web, read , shop, bet, play video games) - reasonable only for a very select bunch of usersSeeWas WAP a solution looking for a problem?Worst aspect - time taken to get info and generally paying by time used.
18User needs & usability 63% of large software projects go over cost Managers gave four usability-related reasonsusers requested changesoverlooked tasksusers did not understand their own requirementsinsufficient user-developer communication and understanding(Greenberg, 2001)
19Human factors Norman – “Design of everyday things” Most failures of human-machine system are due to poor designs that don’t recognize peoples’ capabilities and fallibility'sThis leads to apparent machine misuse and “human error”Good design always accounts for human capabilities.
20Darn these hooves. I hit the wrong switch again Darn these hooves! I hit the wrong switch again! Who designs these instrument panels, raccoons?
21Human characteristics Designer must take into account variations in human senses and motor abilities:Vision – e.g. depth, contrast, colour blindness, and motion sensitivity.Hearing - e.g. audio cues must be distinct.Touch: e.g. keyboard and touchscreen sensitivity.Motor control/ hand-eye coordination e.g use of pointing devices.Physical strength, coordination.Not yet for taste and smell!
22Cognitive and perceptual abilities There are many aspects to human cognitive abilities. For example:short-term memorylong-term memory and learningproblem solving, decision makingattention and set (scope of concern)perception & recognition
23from Science magazineIn 1988, the Soviet Union’s Phobos 1 satellite was lost on its way to Mars, when it went into a tumble from which it never recovered. “not long after the launch, a ground controller omitted a single letter in a series of digital commands sent to the spacecraft. And by malignant bad luck, that omission caused the code to be mistranslated in such a way as to trigger the [ROM] test sequence [that was intended to be used only during checkout of the spacecraft on the ground]”Failure of attention, memory, in controllerOR failure in design process???
24Factors affecting cognitive, perceptual & motor performance Arousal, vigilance, fatigueCognitive (mental) loadBoredom, isolation, sensory deprivationAnxiety and fearIllness, ageingDrugs and alcoholCircadian rhythms, sleep deprivationWas that controller tired, overexcited, trying to do /remember too many things at once, very anxious, unwell, old, drunk, hadn’t slept for two days…
25Personality factorsThere is no single taxonomy for identifying user personality types.Designers must be aware that populations are subdivided and that these subdivisions have various responses to different stimuli.Myers-Briggs Type Indicator (MBTI)extroversion versus introversionsensing versus intuitionperceptive versus judgingfeeling versus thinkingWhy does this matter?For example: sensing types – good at routine and precision whereas intuitive types like change and challenge but are often imprecise…
26Awareness of cultural and international diversity Characters, numerals, special characters, grammar, spellingL-to-r vs r-to-l vs vertical input & readingDate and time formatsNumeric and currency formatsTelephone numbers and addressesNames and titles (Mr., Ms., Mme.)Social-security, national id & passport numbersEtiquette, policies, tone, formality, metaphorsSee Preece etc slides for examples
27Which are universal and which are culturally-specific? Learned arbitrary conventions - like red triangles for warningBuddhists – white is mourning, west is used in weddings for celebration4 is unlucky in Chinese, 13 in west…
28Users with disabilities Need to plan early to accommodate users with disabilities as costs may be very high laterSome countries have laws which specify requirements to comply with equal opportunity legislationSee list of guidelines
29Current Computing Systems Human factors and HCI design impact on all of the large variety of current and emerging computer systems.However, the impact of various human factors and design decisions depends on the nature of the system.
30System types: Critical systems Examples: air traffic control, nuclear reactors:High costs, reliability and effectiveness are expected.Lengthy training periods are acceptable to provide error-free performance.Subject satisfaction is less an issue due to well motivated users. Retention via frequent use and practice.Designing this type of system will require quite different approach and specific evaluation criteria
31Systems types: Commercial/industrial Examples: banking, production control, banking, insurance, order entry, inventory management, reservation, billing, and point-of-sales systems:Lower cost may sacrifice reliability.Training is expensive, learning must be easy.Speed and error rates are relative to cost, however speed is the supreme concern. Subject satisfaction is fairly important to limit operator burnout.Often have to train lots of people, and may have large staff turnover also.Eg system to support directory assistance found that .8 secs reduction in call time meant 40 million per annum savings
32System types: Office/home/entertainment Examples: Word processing, electronic mail, computer conferencing, and video games, education:Choosing functionality is difficult because the population has a wide range of both novice and expert users.Competition causes the need for low cost.Subject satisfaction is very important.
33System types: ???Examples: Artist toolkits, statistical packages, and scientific modelling systemsBenchmarks are hard to describe due to the wide array of tasksWith these applications, the computer should "vanish" so that the user can be absorbed in their task domain.Difficult to design and evaluate….
34System engineering versus interface design System engineering evaluated by:Coverage of task functionality.Reliability, security, integrity of system and data.Standardization, consistency and portability.Time and budget considerations.
35User interface evaluation Depends largely on human factors criteria:1. Learning time2. Performance speed3. Error rates of users4. Retention over time5. Subjective satisfactionHow long does it take for typical members of the community to learn relevant task?How long does it take to perform relevant benchmarksHow many and what kinds of errors are commonly made during typical applications?Frequency of use and ease of learning help make for better user retentionAllow for user feedback via interviews, free-form comments and satisfaction scales.
36HCI is concerned with… Humans and machines jointly performing tasks The structure of communication between human and machineHuman capabilities to use and learn to use machinesAlgorithms and programming of the interfaceEngineering concerns that arise in designing and building interfacesThe process of specifying, designing, and implementing interfacesDesign trade-offs
375 Areas of HCI The nature of human-computer interaction Use and context of computersHuman characteristicsComputer system and interface architectureDevelopment processes
39Nature of Human-Computer Interaction Overviews of, and theoretical frameworks for, topics in human-computer communication
40N1 The Nature of Human-Computer Interaction Points of viewHCI as communicationagent paradigm, tool paradigmHuman / system / tasks divisionObjectives or goalsproductivity, user empowermentHistory and intellectual rootsHCI as an academic topicjournals, literaturerelation to other fieldsscience vs. engineering vs. design aspects
41Use and Context of Computers Applications of computersApplications and appropriate interfacesThe general social, work, and business contextIn addition to technical requirements, an interface may have tosatisfy quality-of-work-life goals of a labor unionmeet legal constraints on "look and feel“position the image of a company in a certain marketGeneral problems of fitting computers, uses, and context of use together
42U1 Social Organization and Work The human as an interacting social beingThe nature of workHuman and technical systems mutually adapt to each other and must be considered as a wholeModels of human activity, groups, organizationsModels of work, workflow, cooperative activityOrganizations as adaptive open systemsImpact of computer systems on work and vice versaComputer systems for group tasks, case studiesQuality of work life and job satisfaction
43U2 Application Areas Characterization of application areas Document-oriented interfacesCommunications-oriented interfacesDesign environments: programming environments, CAD/CAMOn-line tutorial and help systemsMultimedia information kiosksContinuous control systems: (process control systems, simulators, cockpits, video games)Embedded systems (Copier controls, elevator controls, consumer electronics and home appliances)
44U3 Human-Machine Fit and Adaptation Design addresses ‘fit’ between the object and its useAdjustments can be made(1) at design time or at time of use(2) by changing the system or the user(3) by the users or by the system.Adaptive systemsTheories of system adoptionCustomizing and tailoringCompatible users and systemsUser adaptation: learning, trainingUser guidance: help, documentation, error-handling
45Human Characteristics human information-processing characteristicshow human action is structuredthe nature of human communicationhuman physical and physiological requirements
46H1 Human Information Processing The human as a processor of information.Models of cognitive architecturePhenomena and theories ofmemoryperceptionmotor skillsattention and vigilanceproblem solvinglearning and skill acquisitionmotivationUsers' conceptual modelsModels of human actionHuman diversity, including disabled populations
47H2 Language, Communication and Interaction Language as a communication and interface mediumAspects of language: syntax, semantics, pragmaticsFormal models of languageConversational interactionturn-taking, repairSpecial languagesgraphical interaction, query, command, production systems, editorsInteraction reusehistory lists
48H3 Ergonomics Human anthropometry and workspace design Arrangement of displays and controlsHuman cognitive and sensory limitsSensory and perceptual effects of display technologiesControl designFatigue and health issuesFurniture and lighting designTemperature and environmental noise issuesDesign for stressful or hazardous environmentsDesign for the disabled
49Computer System and Interface Architecture Machines have specialized components for interacting with humansTransducers for moving information physically between human and machineHave to do with the control structure and representation of parts of the interaction
50C1 Input and Output Devices Technical construction of devicesInput devicesMechanics and performanceDevices for the disabledHandwriting and gestures, virtual keyboardSpeech inputEye tracking, EEG, other biological signalsOutput devicesSound and speech output3D displays, motion (e.g., flight simulators)Device weight, portability, bandwidth, sensory mode
51C2 Dialogue Techniques Techniques for interacting with humans Dialogue Interaction TechniquesDialogue type and techniquesNavigation, orientation, error managementAgents and AI techniquesMulti-person dialoguesDialogue IssuesReal-time responseManual control theorySupervisory control, automatic systems, embedded systemsStandards"Look and feel," intellectual property protection
52C3 Dialogue Genre Conceptual uses for the technical means Concepts arise in any media discipline (film, graphic design)Interaction metaphorsContent metaphorsPersona, personality, point of viewWorkspace modelsTransition managementTechniques from other media (film, theater, graphic design)Style and aesthetics
53C4 Computer GraphicsConcepts from computer graphics that are useful for HCIGeometry in 2- and 3-D space, linear transformationsGraphics primitives and attributesSolid modeling, splines, surface modeling, hidden surface removal, animation, rendering algorithms, lighting modelsColour representation, colour maps, colour ranges of devices
54C5 Dialogue Architecture Software architectures and standardsLayers and windowsScreen imaging models (e.g. postscript)Window manager models, analysis of major window systemsModels for specifying dialoguesMulti-user interface architecturesStandardization and interoperability
55Development Process Both design and engineering The methodology and practice of interface designThe relationship of interface development to the engineering of the rest of the system
56D1 Design Approaches The process of design Alternative system development processesChoice of method under time/resource constraintTask analysis techniquesDesign specification techniquesDesign analysis techniquesGraphic design basicsIndustrial design basicsDesign case studies and analyses of design
57D2 Implementation Techniques and Tools Tactics and tools for implementation.Relationships among design, evaluation, and implementationIndependence and reusability, application independence, device independencePrototyping techniquesDialogue toolkitsObject-oriented methodsData representation and algorithms
58D3 Evaluation Techniques Philosophy and methods for evaluationsProductivityMeasuresTimeErrorsLearnabilityDesign for guessingPreferenceTesting techniques, link testing to specificationsFormative and summative evaluationMethods from psychology and sociologyEthics
59D4 Example Systems and Case Studies Classic designs that serve as examples of HCICommand-orientedGraphics-orientedFrame-basedUser-defined
61Where does GUI fit in? U3 human-machine fit and adaptation H1 human information processingH2 language, communication and interactionC1 input and output devicesC2 dialog techniquesC3 dialogue genreC4 computer graphicsC5 dialogue architectureD1 design approachesD3 evaluation techniques
62ReferencesACM Special Interest Group on Computer-Human Interaction (SIGCHI). ACM SIGCHI is an international, interdisciplinary forum for the exchange of ideas about the field of human-computer interaction.Norman, D. A. (1998). The Design of Everyday Things. New York, New York, USA: Basic Books.Shneiderman, B., & Plaisant, C. (2005). Designing the User Interface: Strategies for Effective Human-Computer Interaction (Fourth ed.). USA: Pearson Education, Inc.Stone, D., Jarrett, C., Woodroffe, M., & Minocha, S. (2005). User Interface Design and Evaluation. San Francisco, California, USA: Elsevier.