HCI Midterm
Forgiveness
AFTER you make an error... -minimize negative consequences of failure -reverse errors that occur
Confirmation
BEFORE you might make an error... -acknowledge critical actions -warn of imminent related threats
CMC
Computer mediated communication
Organization
design implication: how you present is as important as what you present -grouping: logical clusters -spacing: use to designate groups -labelling: make group meaning clearer
Internal Consistency
designing operations to behave comparably within an application -difficult within complex interfaces
External Consistency
designing operations, interfaces, etc. to be the same across applications and devices
Command line
early interfaces required the user to type in commands that were typically abbreviations at the prom symbol appearing on the sumpter display, which the system responses to. command line interfaces have been largely superseded by graphical interfaces that incorporate commands such as menus and icons. where command line interfaces continue to have an advantage is when users find them easier and faster to use than menu-based systems
Pen-based interfaces
enable people to write, draw, select, and move objects at an interface using lightpens or styluses that capitalize on the well-honed drawing skills that are developed from childhood. the pen works by recognizing a special non-repeating dot pattern that is printed on the paper
Virtual Reality
technologies that: -track users' movements -render virtual environments accordingly -layers of sensory information -attempt to replace the physical world with the virtual high sense of immersion and presence
IKEA effect
the act of creating a thing increases the perceived value of that thing to the creator -creating or partially creating a thing (assembling furniture) makes it more valuable to the creator -the level of effort invested in creation corresponds to its level of valuation
Factor of Safety
the design of a system beyond expected loads to offset the effects of unknown variables and prevent failure -increasing the factor of safety of a design is a reliable method of preventing catastrophic failure -the size of the factor of safety should correspond to the level of uncertainty in the design parameters
mere exposure effect
the more people are exposed to a stimulus, the more they like it -strongest during the first 10-20 exposures -brief exposures are more effective than long exposures
WIMP
the original WIMP comprises: -windows -icons -menus -pointing device the first generation of WIMP interfaces was primarily boxy in design; user interaction took place through a combination of windows, scroll bars, etc.
garbage in, garbage out
the quality of system output is largely dependent on the quality of system input -the garbage in metaphor refers to two categories of input problems: type and quality -problem of type example: entering a phone number into a credit card number field -problem of quality example: entering a phone number into a phone number field, but entering it incorrectly
Iconic Representation
the use of pictorial images to improve recognition and recall -4 kinds of icons: resemblance, exemplar, symbolic, and arbitrary -resemblance icons look like the things they portray -exemplar icons are examples of things -symbolic icons make use of familiar symbols -arbitrary icons are used to establish industry standards or international communication
Serial position effects
things presented at the beginning and end of a sequence are more memorable than things presented in the middle
80/20 Rule
-80% of use = 20% of features -design goals: make 20% highly visible, remove extraneous features, use hierarchy to use rarely used options
Legibility
-9-12 point font on paper, 18+ on slides -proportionally spaced donuts are preferred to monospaced -vertical space between lines of text should be slightly larger than font size - serif and sans serif typefaces are equally legible (serifs are the flourishes at the end of each character- "sans" mean "without": no flourishes) -high contrast more legible than low contrast -mixed case is better -justified and unjustified text are: left justification recommended in web design, we read left to right
pleasure model
-physio-pleasure: sensory experiences (touch, taste) -socio-pleasure: social aspects -psyscho-pleasure: emotional and cognitive reactions -ideo-pleasure: values match
Annotating and cognitive tracing
-annotating involves modifying external representations, such as crossing off or underlining items -cognitive involves externally manipulating items into different order or structures
Performance Load
-cognitive: too much stuff, hard to think through everything -kinematic- physical -more load= more errors, more time, reduced success -design goal: minimize load (limit information, provide memory aids)
Media Equation
-computers as social actors (CASA) -human brains evolved when only humans were social -media can exhibit social behavior -people react to media like real world stimuli: social (be polite), natural (popcorn will spill), mindless (don't even know we're doing it)
Gesture Based Interfaces
-don't have to be natural -natural mapping can be limiting -actions with no real-world equivalent? (homunculus flexibility)
User-centered design principles
-early focus on users and tasks -observe, interview, learn any way you can - involve them throughout process -empirical measurement using quantifiable and measurable usability criteria -interactive design (study, design, test, repeat)
Constraints
-elements of a design that prevent you from misusing a product -promote user safety (training wheels)
Visibility
-function is apparent and/or easily recalled -can I tell... how to use this? what will happen when I manipulate it? what the current status of the device is?
Signal-to-Noise Ratio
-how much task-relevant information vs. irrelevant information -irrelevant information is distracting: takes up space, mental processing power -goal: eliminate sources of noise
external cognition
-human brain has limited capacity -need help processing and remembering info -computational offloading: using a tool or device to carry out a computation -externalizing: transforming info into external, representations to reduce memory load -design implication: provide external representations to reduce memory load and facilitate offloading (data visualization)
4 Types of interaction
-instructing: where users issue instructions to a system (typing in commands, selecting options, pressing buttons) -conversing: where users have a dialog with a system (users can speak via interface or type in questions to which the system replies via text or speech output) - manipulating: where users interact with objects in a virtual environment or a physical space by manipulating them (opening, holding, closing, placing) -exploring: where users move through a virtual environment or a physical space (3D space, augmented and virtual reality)
Natural User Interfaces
-interface becomes effectively invisible: no physical device to manipulate, usually gesture based -often modeled on physical world: mental models
5 Hat Racks
-location (geographical or spatial): photograph maps -alphabetical: files within a folder -time (chronological): email -category: based on similarity or relatedness, tags -hierarchy (continuum) : magnitude of a certain trait, most frequently accessed
Benefits of Ubiquitous Computing
-make individuals more aware of people, less aware of technology -make things faster/easier -accomplish things anytime/anywhere: external cognition
Turing Test
-mindful assessment of agency (computer controlled and human controlled) -spam emails and texts -phone operators/services -email or chat help -catfishing Example: asking the same question twice
aesthetic-usability effect
-people believe that a more aesthetic product is easier to use regardless of actual performance :buying something on looks alone :beauty bias -first impressions --> long term attitudes :hard to shake first impressions
performance vs. preference
-people don't always know what is good for them -disparity between focus group use and actual use -makes design success unpredictable :ingrained attitudes :individual differences
Social influence in virtual environments
-people judge mediated stimuli by: behavioral realism and agency -human-like avatars are more credible than non-human-like avatars
User-centered design benefits
-products that are easier to use: sell better, develop and/or retain brand and reputation -keep products on schedule: identify problems earlier in the process, save money -helo designers understand audience: what people want and need, one size doesn't fit all, identify incorrect assumptions about users
Operant Conditioning
-provide rewards or punishments after target behavior Best design practices -provide immediately (stronger association) -partial reinforcement: do not over reward, provide irregularity; otherwise users quit when rewards stop
recognition vs. recall
-recognizing easier than recalling (images are easier than words) -implications for interface design (command based: recall commands, GUI's: recognized visually-based options)
color effects
-red: dominance, sexuality, promotes competitiveness -blue: open-minded, friendly, trustworthy, promotes creativity -green: safety, security, nature, limits stress -yellow: visibility, energy, grabs attentions -black: aggressive, evil -white: passivity, goodness both black and white are classy, associated with status and authority
Mapping
-relationship between controls and their effects -goal is natural mapping (placement and movement of controls is logical and parallels the effects)
Classical Conditioning
-repeated association (good/happy things= positive, bad/sad/angry things= negative) -unconditioned (natural) stimulus --> unconditioned (natural) response -over time: conditioned stimulus --> conditioned response design implications -small, recurring rewards -associate pleasant things with desired behavior (nostalgic, unique) -associate unpleasant things with desired behavior -colors, sounds, messages
Reward in Design
-require user action: more invested if they have to earn it -reward early in the process: illusive superiority and Dunning-Kruger effect: everyone thinks they're better than average -make it feel like skill, not luck: users experience mastery competence -make rewards feel possible: near-wins, variety of rewards -capitalize on FOMO: limit time or number of rewards, visibility of others' rewards
Mental Models
-schema, scripts -cognitive structure: developed over time, provides a general idea of how something works, accessed when we encounter a relevant cue -saves cognitive effort -often incomplete, inaccurate, or biased
Hicks' Law
-the more options, the more time it takes to make a decision -paradox of choice: more options --> less happiness -design goals: don't want to overwhelm the user with choices- flexibility tradeoffs, and organize options (hierarchy, modularity)
Augmented Reality
-virtual representations superimposed on physical objects, devices, or locations - doesn't have to replace reality like VR, but adds to it
Multitasking: 3 types, effects
-visual distraction -cognitive distraction -manual distraction specific to texting and driving but to apply to other things -diminishes: learning, memory of content, memory of experience, enjoyment of content
Feedback
-what is happening? -am I doing it right? - you're doing it wrong
Usability goals
1. effectiveness: how well a product does what it should 2. efficiency: how a product helps users perform a task 3. safety: protecting user (physical and from errors) 4. usability: actually has the functions I need 5. learnability: how difficult it is to learn, figure out the product 6. memorability: how difficult it is to remember how to use
Form Follows Function
1. functionally design is naturally beautiful 2. aesthetics should never trump usability
User-centered design process
1. understand requirements- study users and tasks: interviews, observations 2. design alternatives- many ways of satisfying requirements 3. prototype- as simple as a sketch, as complex as a working model 4. evaluate- with and without users Then go back to whatever step and cycle through again as needed
Contributions of Licklider
1960's -psychologist -man-computer symbiosis: casual users -"on-line man-computer communication" and "intergalactic computer network"
Contributions of Engelbart
1968: developed first word processor users- real human beings- were his top concern
Dunning-Kruger effect
Everyone thinks they are better than average
Contributions of Sutherland
Grandfather of virtual reality 1962: sketchpad 1968: first virtual reality equipment
HCI
Human Computer Interaction- it is multidisciplinary: engineers, computer scientists, designers, social scientists.
Touch-based interfaces
They work by detecting the presence and location of a person's touch on the display. the flexibility of interacting with digital content afforded by finger gestures has resulted in new ways of experiencing digital content
Features of modern HCI
Today it is near ubiquitous (and often unnoticed). This is because of convergence: machines are talking to each other.
Norman's fundamental argument
You should be able to tell how to use something just by looking at it - which means: inability to use technology is not your fault, and if you can't figure it out the designer failed
Selection bias
a bias in the way evidence is collected that distorts analysis and conclusions -results from the non-random sampling of evidence. it over represents certain aspects of the evidence and under-represents others -example: if only subscribers to a science magazine are surveyed and generalized for the whole population, science-minded viewpoints would be over-represented in the analysis and results
Stickiness
a formula for increasing the recognition, recall, and voluntary sharing of an idea -this explains why certain ideas go viral and become lodged in the cultural consciousness characterized by 6 attributes: -simple: sticky ideas can be expressed simply and succinctly without sacrificing depth -unexpected: sticky ideas contain an element of surprise, which grabs attention -concrete: sticky ideas are specific and concrete, typically using plain language or imagery -credible: sticky ideas are believable, often communicated by a trusted source -emotional: sticky ideas elicit an emotional reaction -stories: sticky ideas are expressible as stories, increasing their memorability and retelling
entry point
a point of physical or attentional entry that sets the emotional tone for subsequent interactions -good entry points feature three elements: minimal barriers, points of prospect, and progressive lures. -entry points enable people to survey available options ex: entrances that provide a clear view of the store layout
Designing Speech Interfaces
a speech or voice user interface is where a person talks with a system that has a spoken language application, like a train timetable, a travel planner, or a phone service. -some researchers focus on making it appear natural like human conversations and some are more concerned with how to help people navigate efficiently through a menu system
flow
a state of immersion so intense that awareness of the real world is lost -flow is attained when high difficulty matches high skill level
cognitive dissonance
a state of mental discomfort due to incompatible attitudes, thoughts and beliefs
biophilia effect
a state of reduced stress and improved concentration resulting from nature views.
Ubiquitous Computing
computers are pervasive and seamlessly integrated into the environment around us
Rosetta Stone
a strategy for communicating novel information using elements of common understanding -involves embedding elements of common understanding in messages, called keys, to act as bridging elements from the known to the unknown -when you don't know what level of understanding a person will have, embed multiple keys based on widely understood or universal concepts
mnemonic devices
a technique for making things easier to remember through patterns of letters or associations
Technology Acceptance Model
adoption predicted by: -perceived usefulness -perceived ease of use
wabi sabi
an aesthetic style that embodies naturalness, simplicity, and subtle imperfection
supernormal stimulus
an exaggerated imitation that elicits a stronger response than the real thing -strongly influence the way people respond to brands, products, and services -exaggerations of things we have evolved to like-attractive features, baby-faces
Flexibility Tradeoffs
as the flexibility of a design increases, the usability and performance of the design decreases -accommodating flexibility entails satisfying a large set of design requirements, which invariably means more compromises and complexity in design -increasing complexity generally decreases performance and usability -example: swiss army knife has many tools that increase its flexibility, but the tools are less efficient and less usable than their standalone equivalent- performance and usability are traded for flexibility
Gulfs of execution and evaluation
gap between user and interface -gulf of execution: how do i do the thing? -gulf of evaluation: did i do the thing right? there has to be feedback in design -bridging gulfs reduces cognitive effort: understanding mental models, scripts, and cognitive abilities helps bridge gulfs
GUI Design
graphical user interface -the basic building blocks of WIMP are still part of the modern GUI used as part of a computer display, but have evolved into a number of different forms and types -toolbars and docks have been incorporated into the GUI
chunking
grouping units of information to make them easier to process and remember
Haptics
haptic interfaces provide tactile feedback, by applying vibration and forces to the person, using actuators that are embedded in their clothing or a device they are carrying, such as a smartphone or smartwatch
Hierarchy
hierarchies are the simplest way to visualize and understand complex information -3 types: trees, nests, and stairs -tree: locate child elements below or to the right of parent elements, forming a triangle. used to represent organizations and high-level maps -nest: locate child elements within parent elements. used to group information and represent logical relationships -stair: stack child elements vertically below parent elements, as an outline. used to represent complex structures that change over time -use tree to represent moderate complexity, nest to represent simple, and stair to represent complex
Errors and error messages
offers feedback guidelines -avoid terms like fatal, invalid, illegal, bad -avoid uppercase and long code numbers -positive, courteous tone -reinforce with audio -consistent appearance -precise, not vague, messages -constructive instructions
Interface Metaphors
intended to provide familiar entities that enable people to readily understand the underlying conceptual model and know what to do at an interface (trashcan)
Accessibility
making designs usable by as many people as possible without modification -perceptibility: everyone can perceive design, regardless of sensory abilities -operability: everyone can use design, regardless of physical abilities -simplicity: everyone can understand design, regardless of mental abilities
Modularity
managing system complexity by dividing large systems into smaller, self-contained systems -involves identifying groups of functions in systems, and then transforming those groups into self-contained units or modules
Theories
many theories have been imported into HCI providing a means of analyzing and predicting performance of users carrying out tasks for specific kinds of computer interfaces and systems. one of the main benefits pf applying such theories in interaction design is to help identify factors relevant to the design and evaluation of interactive products
user frustration and design implications
misuse -perceived affordances doesn't equal design intent -false affordances misdirection of misinterpretation -outcomes don't match expectations failures -error messages -feedback: something went wrong -user predisposed to be frustrated -design of messages can make matters worse implications for design: design to prevent error... -visibility -constraints -feedback -forgiveness ...but design to cope with negative user experience -level of frustration -context appropriate response -desired user actions -resolutions/recovery
Models
models are typically abstracted from a theory coming from a contributing discipline that can be directly applied to interaction design. these are intended to explain certain things- the way users will interact with certain technologies
CAVE
physical environments have been developed using embedded sensor technologies and other location-detected technologies
Picture Superiority Effect
process words vs. pictures -it is easier to remember pictures over words (look at chart in notes)
Affordances
properties that indicate how an object can or should be used by an actor -physical affordances (also inherent or structural): built into a product -perceived: what user identifies (not necessarily what designer intended for it) -hidden: a physical affordance that is not perceived -false: a perceived affordance that is not really there
Skeuomorphism
retaining ornamental features from past designs/objects in new technologies -compass on iphone -notes on iphone -ibooks bookshelf 2 reasons it is used - tied to mental models -nostalgic feeling, we like it, pleasing
contour bias
shapes convey emotion -angular, pointy=threat -curves, smooth= more positive, friendly tech used to be sharp/boxy -now seen as dated -some contours also promote safety
Sharable and Collaborative Interfaces
shareable interfaces provide more opportunities for flexible kinds of collaboration compared with single-ser PC's, through enabling co-located user to simultaneously interact with digital content. they are also seen as more natural than other technologies
Aesthetic Consistency
similar style and appearance across a family of products -facilitates ease of use and branding
Ockham's razor
simple designs should be preferred -given two functionally equivalent designs, the simpler design should be preferred -cutting unnecessary elements from a design
Directed Dialogue
system controls conversation -ask specific questions, require specific responses
interference effects
things that trigger conflicting though processes reduce thinking efficiency -this occurs when nonessential mental processes interfere with essential mental processes, increasing errors and sowing task performance -nonessential mental processes can be triggered by conflicting meanings, distractions in the environment and memories that are irrelevant to the task at hand -example: a green stop button triggers a mental process for "go" because of the color green and a mental process for "stop" because of the label stop
depth of processing
thinking hard about a thing improves the likelihood that it can be recalled -the key factors determining recall are distinctiveness, relevance, and degree of elaborative rehearsal
threat detection
threatening things are detected more efficiently/quickly than nonthreatening things
Paradigms
to follow a particular paradigm means adopting a set of practices that a community has agreed upon including: -the questions to be asked and how they should be framed -the phenomena to be observed -the way in which findings from studies are to be analyzed and interpreted
emotional design model
types -visceral: fast judgment: good/bad, danger/not (appearance of the product) -behavioral: reactions (pleasure and effectiveness of use) -reflective: thinking influences behavior (memories, self image) -emotional state changes how we think (angry, frightened--> narrow focus, tense body, less tolerant) (happy --> less focus, more tolerant, more creative) -need to consider emotional reactions for usability: can get away with more with leisure vs. task products
Von Restorff Effect
uncommon things are easier to recall than common things -results from the increased attention given to novel things relative to other things -the strength of the effect is a function of the novelty of the things to be recalled -apply this effect to attract attention and increase memorability
Tangible Interfaces
use sensor based interaction, where physical objects are coupled with digital representations. when a person manipulates the physical object, it is detected by a computer system via the sensing mechanism embedded in the physical object, causing a digital effect to occur, such as a sound, animation, or vibration
Functional Consistency
use similar elements or iconic representations for similar functions/tasks -transferability, learnability, and memorability
Head up displays
used in military and civil planes to aid pilots when landing during poor weather conditions. This provides electronic directional markers on a fold down display that appears directly in the field of view of the pilot.
Attention
users pay attention to info when: -they have a clear goal and info is salient -structure info to grab attention
Redundancy
using back-up or fail-safe elements to maintain system performance in the event of failure -most reliable method of preventing catastrophic failure
Visions
visions of the future are another driving force that frame research and development in interaction design. these visions provide concrete scenarios of how society can use the next generation of imaged technologies to make their lives more safe, comfortable, informative, and efficient. they also provide food for thought for researchers
Head-mounted displays
wearable technology that allows you to access information and do other tasks. this allows them to do these things without having to take out a hand held device- this is a more hands free technology