Presentation on theme: "The Psychopathology of Everyday Things"— Presentation transcript:
1The Psychopathology of Everyday Things Chapter 1The Psychopathology of Everyday Things
2Characteristics of a Good CHI Project Not just a standard, everyday UICan aim at a new UI; there is a lot of effort in social, mobile, ubiquitous technologies …One possibility for more traditional interfaces is to think of what is wrong with it; aim for betterA third possibility is to add something unique to a common UI typeInteresting cognitive or social issues to addressPeople have limits on their attention, perception, memory, rational thought, etc.Social interactions require awareness, communication, coordination, recovery from breakdowns, etc.
3Chapter 1 The problem of use: discoverability and understanding Types of design: industrial design/interaction design/experience design/human-centered designAffordances and signifiersMappings and feedbackConceptual models and mental modelsThe system image (combined system presentation)Feature creep/usefulness vs. usability/paradox of technologyKnowing what matters to users/customers/etc.
4Bad designsElevator controls and labels on the bottom row all look the same, so it is easy to push a label by mistake instead of a control buttonPeople do not make same mistake for the labels and buttons on the top row. Why not?From:
5Good and bad design What is wrong with the Apex remote? Why is the TiVo remote so much better designed?Peanut shaped to fit in handLogical layout and color-coded, distinctive buttonsEasy to locate buttons
6What to design Need to take into account: Who the users areWhat activities are being carried outWhere the interaction is taking placeNeed to optimize the interactions users have with a productSo that they match the users’ activities and needs
7Understanding users’ needs Asymmetry of interactionNeed to take into account what people are good and bad atTradition and TranscendenceConsider what might help people in the way they currently do thingsNo Arm-Chair QuarterbackingListen to what people want and get them involvedUse tried and tested user-centered methods
8Which kind of design?Lots of terms are used to discuss CHI-related design practicesuser interface design,software design,human-centered design,product design,web design,experience design (UX)interaction designThe meanings vary both in terms of the central focus of the activity (e.g. interface vs. experience) and in whether they view the activity asmore upstream activity (i.e. determining what the software should do) ormore downstream activity (e.g. designing to meet an existing specification, engineering)
10The User ExperienceHow a product behaves and is used by people in the real worldthe way people feel about it and their pleasure and satisfaction when using it, looking at it, holding it, and opening or closing it“every product that is used by someone has a user experience: newspapers, ketchup bottles, reclining armchairs, cardigan sweaters.” (Garrett, 2003)Cannot design a user experience, only design for a user experience
11Visibility • This is a control panel for an elevator • How does it work?• Push a button for the floor you want?• Nothing happens. Push any other button? Still nothing. What do you need to do?It is not visible as to what to do!From:
12Visibility…you need to insert your room card in the slot by the buttons to get the elevator to work!How would you make this action more visible?• make the card reader more obvious• provide an auditory message, that says what to do (which language?)• provide a big label next to the card reader that flashes when someone enters• make relevant parts visible• make what has to be done obvious
13What do I do if I am wearing black? Invisible automatic controls can make it more difficult to use
14Affordances & Signifiers Affordance: Something that can be done with an objectOften misinterpreted as a signifier in CHI discussionsSignifier: Refers to an attribute of an object that allows people to know how to use ite.g. a mouse button invites pushing, a door handle affords pullingSince Norman’s original introduction of the concept in software design, it has been much popularised in interaction design to discuss how to design interface objectse.g. scrollbars to afford moving up and down, icons to afford clicking onWhat do ‘signifiers’ have to offer software design?Interfaces are virtual and do not have signifiers like physical objectsInstead use of interfaces involves learned conventions of mappings between action and effect at the interfaceSome mappings are better than others
15Physical SignifiersHow do these physical objects signify their use? Are they obvious?
16Virtual Signifiers How do the following screen objects afford? What if you were a novice user?Would you know what to do with them?
17Logical or ambiguous design? Where do you plug the mouse?Where do you plug the keyboard?top or bottom connector?Do the color coded icons help?From:
18How to design them more logically (i) A provides direct adjacent mapping between icon and connector(ii) B provides color coding to associate the connectors with the labelsFrom:
20Feedback Sending information back to the user about what has been done Includes sound, highlighting, animation and combinations of thesee.g. when screen button clicked on provides sound or red highlight feedback:“ccclichhk”
21Because Software Signifiers are Learned: Consistency Design interfaces to have similar operations and use similar elements for similar tasksFor example:always use ctrl key plus first initial of the command for an operation – ctrl+C, ctrl+S, ctrl+OMain benefit is consistent interfaces are easier to learn and use
22When consistency breaks down What happens if there is more than one command starting with the same letter?e.g. save, spelling, select, styleHave to find other initials or combinations of keys, thereby breaking the consistency rulee.g. ctrl+S, ctrl+Sp, ctrl+shift+LIncreases learning burden on user, making them more prone to errors
23Internal and external consistency Internal consistency refers to designing operations to behave the same within an applicationDifficult to achieve with complex interfacesExternal consistency refers to designing operations, interfaces, etc., to be the same across applications and devicesLike Apple’s design guidelines on applications
25Conceptual modelNeed to first think about how the system will appear to users (i.e. how they will understand it)A conceptual model is:“a high-level description of how a system is organized and operates.” (Johnson and Henderson, 2002, p. 26)Not a description of the user interface but a structure outlining the concepts and the relationships between themConceptual models can be presented through signifiers in the design and through descriptions and documentation
26Helps the design teamOrient themselves towards asking questions about how the conceptual model will be understood by usersNot to become narrowly focused early onEstablish a set of common terms they all understand and agree uponReduce the chance of misunderstandings and confusion arising later on
27Main componentsMajor metaphors and analogies that are used to convey how to understand what a product is for and how to use it for an activity.Concepts that users are exposed to through the productThe relationships between the conceptse.g., one object contains anotherThe mappings between the concepts and the user experience the product is designed to support
28Mental modelsUsers develop an understanding of a system through learning and using itKnowledge is often described as a mental modelHow to use the system (what to do next)What to do with unfamiliar systems or unexpected situations (how the system works)People make inferences using mental models of how to carry out tasks
29Mental modelsCraik (1943) described mental models as internal constructions of some aspect of the external world enabling predictions to be madeInvolves unconscious and conscious processes, where images and analogies are activatedDeep versus shallow models (e.g. how to drive a car and how it works)
30Everyday reasoning and mental models You arrive home on a cold winter’s night to a cold house. How do you get the house to warm up as quickly as possible? Set the thermostat to be at its highest or to the desired temperature?(b) You arrive home starving hungry. You look in the fridge and find all that is left is an uncooked pizza. You have an electric oven. Do you warm it up to 375 degrees first and then put it in (as specified by the instructions) or turn the oven up higher to try to warm it up quicker?
31Heating up a room or oven that is thermostat-controlled Many people have erroneous mental models (Kempton, 1996)Why?General valve theory, where ‘more is more’ principle is generalised to different settings (e.g. gas pedal, gas cooker, tap, radio volume)Thermostats based on model of on-off switch model
32A classic conceptual model: the spreadsheet Analogous to ledger sheetInteractive and computationalEasy to understandGreatly extending what accountants and others could do
33Why was it so good?It was simple, clear, and obvious to the users how to use the application and what it could do“It is just a tool to allow others to work out their ideas and reduce the tedium of repeating the same calculations.”Capitalized on user’s familiarity with ledger sheetsGot the computer to perform a range of different calculations and recalculations in response to user input
34Another classic8010 Star office system targeted at workers not interested in computing per seSpent several person-years at beginning working out the conceptual modelSimplified the electronic world, making it seem more familiar, less alien, and easier to learnJohnson et al (1989)
36Interface metaphorsDesigned to be similar to a physical entity but also has own propertiese.g. desktop metaphor, search engineExploit user’s familiar knowledge, helping them to understand ‘the unfamiliar’Conjures up the essence of the unfamiliar activity, enabling users to leverage of this to understand more aspects of the unfamiliar functionalityPeople find it easier to learn and talk about what they are doing at the computer interface in terms familiar to them
37Benefits of interface metaphors Makes learning new systems easierHelps users understand the underlying conceptual modelCan be innovative and enable the realm of computers and their applications to be made more accessible to a greater diversity of users
38Problems with interface metaphors Can constrain designers in the way they conceptualize a problem space and limit designers’ imagination in coming up with new conceptual modelsCan conflict with design principlesUsers’ mental model may only be accurate for parts of software connected to the metaphorDifficulty going beyond surface featuresCan inadvertently use bad existing designs and transfer the bad parts overMixed-metaphors can be confusing to usersMay break conventional and cultural rulese.g., recycle bin placed on desktop
39Chapter 1 The problem of use: discoverability and understanding Types of design: industrial design/interaction design/experience design/human-centered designAffordances and signifiersMappings and feedbackConceptual models and mental modelsThe system image (combined system presentation)Feature creep/usefulness vs. usability/paradox of technologyKnowing what matters to users/customers/etc.