HCI-Chapter-1-The-Human-and-The-Computer.pdf

Foundations of Human Computer Interaction  What is Human-Computer Interaction (HCI) ? Daniela Rus, Professor and Director of the MIT Computer Science and Artificial Intelligence Laboratory (CSAIL), not only is a promoter of HCI, but believes wholeheartedly in its pivotal r...

Foundations of Human Computer Interaction  What is Human-Computer Interaction (HCI) ? Daniela Rus, Professor and Director of the MIT Computer Science and Artificial Intelligence Laboratory (CSAIL), not only is a promoter of HCI, but believes wholeheartedly in its pivotal role in shaping our future. As she says; “Future human- computer interactions will make it much easier for people and machines to work together. It will make it possible for machines to support people in cognitive tasks as well as physical tasks. The future holds a lot of possibilities for people and machines working together.”  What is Human-Computer Interaction (HCI) ? From automatically dishing out soap in the restroom to controlling the air-fuel ratio in your car’s engine, computers are everywhere. We interact with them constantly—some more than others—and the interaction is, unfortunately, not always as easy as we hope for.  What is Human-Computer Interaction (HCI) ? HCI is focused mainly on developing empirical understandings of users… The definition of Human-Computer Interaction (HCI) needs to remain quite broad, as it now covers almost all forms of information technology (IT).1 HCI is the study of designing computers and machines so that they best serve their users (i.e. humans). HCI is closely related to the field of User Experience (UX) design and is considered by many to be the forefather of this more modern approach.2 Why does HCI matter? HCI is the study of how computers and machines can serve us better. It might sound simple, but this field is so fast-moving and exciting in the 21st century that it’s helped to bring around some of our proudest inventions, like virtual reality, self-driving cars, and all of your beloved touch screen technology. Why does HCI matter? “I think it’s a strange thing that in software, perhaps we’ve been so insensitive to our users that we’ve had to invent this term. But the truth is that user interaction design is the very essence of design.” — Daniel Jackson, Professor of Computer Science, MIT CSAIL What is the future of Human-Computer Interaction? Looking into the potential of where HCI might lead us can feel as if you’re diving into a sci-fi novel. That’s because, naturally, HCI wants technology to be as normal and easily accessible in our day-to-day life as possible, which creates a window into a seemingly futuristic world.  1. Dexta haptic gloves were invented to mimic touch sensations of hardness, softness, springiness, and more, when using virtual reality. The gloves simulate these sensations by locking and unlocking the user’s fingers’ joints to different degrees as they interact with objects with their VR experience. …watch video clip  2. Pre-touch sensing helps your smartphone read your mind (almost). When launched, pre- touch phones should be able to understand how the user is holding it or what fingers are approaching the screen to predict what the user wants to do. This would give the sense that your phone can read your mind as it performs actions before you even give your phone a clear command.. …watch video clip 3. PaperID is the next attempt at digitizing paper, by making it into a touchscreen. This new technology supposedly will give paper “the ability to sense its surroundings and respond to gesture commands, as well as connect to the Internet of Things”. The idea is to link the physical and the digital world together—imagine “a page of sheet music that can detect the motion of a conductor’s wand being waved over it”.…watch video clip  “THE HUMAN” Information input/output: visual, auditory, haptic, movement. Information stored in memory: sensory, short-term, long-term. Information processed and applied: reasoning, problem-solving, skill, error. Emotion influences human capabilities. (ability, competency) Each person is different.  VISION TWO (2) STAGES: 1. Physical reception/function of stimulus. (causes an action or response) 2. Processing and interpretation of stimulus.  THE EYE – Physical reception Mechanism for receiving light and transforming it into electrical energy. LIGHT reflects from objects. Retina contains rods for low light vision and cones for color vision. Ganglion cells (collect visual information) detect pattern and movement.  INTERPRETING THE SIGNAL 1. Size and Depth 2. Brightness 3. Color  SIZE AND DEPTH Visual angle: indicates how much of view an object occupies. (relates to size and distance from eye)  SIZE AND DEPTH Visual acuity(sharpness): is the ability to perceive detail. (limited) - Familiar objects perceived as constant size (in spite of changes in visual angle when far away) size constancy  SIZE AND DEPTH Cues like overlapping help perception of size an depth.  BRIGHTNESS Subjective reaction to levels of light (sensitivity to light) Affected by luminance (intensity of light) of an object. Visual acuity increases with luminance as does flicker  COLOR Made up of hue, intensity, and saturation. Hue: a color and a shade of a color. Intensity: refers to the purity of a hue. Saturation: refers to the dominance of hue in the color. 8% males and 1% females are color blind.  INTERPRETING THE SIGNAL The visual system compensates for: - movement - changes in luminance. Context is used to resolve ambiguity Optical illusions sometimes occur due to over-compression  the Muller Lyer illusion the Ponzo illusion  INFORMATION INPUT/OUTPUT 1) Visual 2) Auditory 3) Haptic 4) Movement  VISUAL: Reading Visual patterns are perceived. Decoded using internal representation of language. Interpreted using knowledge of syntax, semantics, and pragmatics. Involves saccades and fixations.  Syntax: the arrangement of words and phrases to create well-formed sentences in a language. Semantics: concerned with meaning, such as sense and implication. Pragmatics: focuses on conversational implicature, which is a process in which the speaker implies and a listener infers. Saccades: a rapid movement of the eye between fixation points. Fixations: an unnaturally strong interest in something or someone.  AUDITORY: Hearing Provides information about environment. Physical apparatus: 1.) Outer ear: protects inner and amplifies or increases sound. 2.) Middle ear: transmits sound waves as vibrations to inner ear. 3.) Inner ear: chemical transmitters are released and cause impulses in auditory nerve.  AUDITORY: Hearing Sound Pitch: sound frequency. Loudness: amplitude. Timbre: type or quality. Humans can hear frequencies from 20Hz up to 15KHz. Auditory system filters sounds and can attend to sounds over background noise.  HAPTIC: Touch Provides important feedback about environment. May be the key sense for someone who is visually impaired. Stimulus perceived via receptors in the skin: Thermoreceptors: heat and cold. Nociceptors: pain. Mechanoreceptors: pressure or tension.  MOVEMENT Time taken to respond to stimulus: reaction time + movement time. Movement time is dependent on age, fitness, etc. Reaction time is dependent on stimulus type: Visual: 200ms. Auditory: 150ms. Pain: 700ms.  INFORMATION STORED IN MEMORY 1) Sensory 2) Short-term 3) Long-term  SENSORY MEMORY Also known as working memory. Buffers for stimuli received through senses. Iconic memory: visual stimuli. Echoic memory: aural stimuli. Haptic memory: tactile memory.  SHORT-TERM MEMORY Scratch pad for temporary recall. Rapid access: 70ms. Rapid decay: 200ms.  LONG-TERM MEMORY Repository for all our knowledge. - Slow access. - Slow decay. - Huge/unlimited capacity.  LONG-TERM MEMORY TWO (2) TYPES: 1. Episodic – serial memory of events. 2. Semantic – structured memory of facts, concepts, and skills. Semantic LTM is derived from Episodic LTM.  SEMANTIC MEMORY STRUCTURE It provides access to information. It represents relationships between bits of information. It supports inference -- a conclusion reached on the basis of evidence and reasoning.  MODEL: SEMANTIC NETWORK Inheritance – child nodes inherit properties of parent nodes. Relationships between bits of information explicit and precise. It supports inference through inheritance.  MODELS OF LONG-TERM MEMORY 1. Frames – information organized in data structures. Slots in data structures instantiated with values for instance of data. 2. Scripts – models of stereotypical information required to interpret situation. It has elements that can be instantiated with values of context.  MODELS OF LONG-TERM MEMORY 3. Production rules – representation of procedural knowledge. Condition/Action rules: “If condition is matched, then use rule to determine action.”  LTM – Storage of Information Rehearsal – information moves from STM to LTM. Total time hypothesis – amount retained proportional to rehearsal time, amount of time is equal to amount of learning. Distribution of practice effect optimized by spreading learning over time.  LTM – Forgetting Decay – information is lost gradually but very slowly. Interference Retroactive interference: new information replaces old. Proactive inhibition: old may interfere with new.  LTM – Retrieval Recall – information reproduced from memory can be assisted by cue like categories or imagery. Recognition – information gives knowledge that it has been seen before. It is less complex.  INFORMATION PROCESSED AND APPLIED 1) Reasoning 2) Problem-solving 3) Skill 4) Error  REASONING Deductive reasoning - derive logically necessary conclusion from given premises; logical / reasonable thinking. - when truth and logical validity clash.  REASONING Inductive reasoning - generalizes from cases seen to cases unseen. - assuming; can or cannot be true.  REASONING Abductive reasoning - reasoning from event to cause. - can lead to false explanations.  PROBLEM-SOLVING Process of finding solution to unfamiliar tasks using knowledge. Several theories: 1. Gestalt theory - problem solving form both productive and reproductive. - attractive but not enough evidence to explain insight.  PROBLEM-SOLVING 2. Problem space theory - problem solving involves generating states using legal operators. - operates within human information processing system.  SKILL ACQUISITION Skilled activity characterized by chunking. Conceptual rather than superficial grouping of problems. Information is structured more effectively.  ERRORS TWO (2) TYPES: 1. Slips - right intention, but failed to do it right. - causes poor physical skill. 2. Mistakes - wrong intention, misinterpreted. - causes incorrect understanding.  EMOTION Emotion clearly involves both the cognitive and physical response to stimuli. It is the biological response to physical stimuli called affect – influences how we respond to situations. Positive affect: creative problem-solving. Negative affect: narrow thinking. “Negative affect can make it harder to do even easy tasks; Positive affect can make it easier to do difficult tasks.” -Donald Norman  EMOTION Various theories of how emotion works: 1. James-Lange: Emotion is our interpretation of a physiological response to stimuli. 2. Cannon: Emotion is a physiological response to a stimuli. 3. Schacter-Singer: Emotion is the result of our evaluation of our physiological response, in the light of the whole situation we are in.  SKILL ACQUISITION Skilled activity characterized by chunking. Conceptual rather than superficial grouping of problems. Information is structured more effectively.