HCI Review PDF

COMPONENTS OF HCI: User Interface – Input devices, output 1. User – By "user", we may mean an devices, dialogue structures, use of colour, individual user, a group of users working icons, commands, navigati...

COMPONENTS OF HCI: User Interface – Input devices, output 1. User – By "user", we may mean an devices, dialogue structures, use of colour, individual user, a group of users working icons, commands, navigation, graphics, together. An appreciation of the way people's natural language, user support, multimedia, sensory systems (sight, hearing, touch) relay Task Factors – Easy, complex, novel, task information is vital. allocation, monitoring, skills 2. Computer – When we talk about the Constraints – Cost, timescales, budgets, computer, we're referring to any technology staff, equipment, buildings ranging fro desktop computers, to large scale System Functionality – Hardware, software, computer systems. application 3. Interaction – There are obvious differences Productivity Factors – Increase output, between humans and machines. In spite of increase quality, decrease costs, decrease these, HCI attempts to ensure that they both errors, increase innovation get on with each other and interact DICIPLINES CONTRIBUTING TO HCI: successfully. A. Computer Science GOALS OF HCI: technology The goals of HCI are to produce usable and safe software design, development & systems, as well as functional systems. In order to maintenance produce computer systems with good usability, User Interface Management Systems developers must attempt to: (UIMS) & User Interface Development understand the factors that determine how Environments (UIDE) people use technology prototyping tools develop tools and techniques to enable graphics building suitable systems B. Cognitive Psychology achieve efficient, effective, and safe information processing interaction capabilities put people first limitations USABILITY OF HCI: cooperative working It is one of the key concepts in HCI. performance prediction It is concerned with making systems easy to learn C. Social Psychology and use. A usable system is: Social & organizational structures Easy to learn D. Ergonomics/Human Factors Easy to remember how to use hardware design Effective to use display readability Efficient to use E. Linguistics Safe to use Natural language interfaces enjoyable to use F. Artificial Intelligence FACTORS IN HCI: Intelligent software Organisation Factors – Training, job design, G. Philosophy, Sociology & Anthropology politics, roles, work-organisation Computer supported cooperative work Environmental Factors – Noise, heating, (CSCW) lighting, ventilation H. Engineering & Design Health and Safety Factors graphic design The User – Cognitive processes and engineering principles capabilities, Motivation, enjoyment, HUMAN THINGKING: satisfaction, personality experience Information is processed and applied: Comfort Factors – Seating, equipment, reasoning Skill acquisition layout. problem solving Error THINKING – REASONING: Techniques for evaluation - Psychology also Reasoning – is the process by which we use provides a range of empirical techniques the knowledge we have to draw conclusions which we can employ to evaluate our designs or infer something new about the domain of and our systems. interest. THE COMPUTER IN HCI There are a number of different types of reasoning: Standard Input Devices: Deductive – reasoning derives the logically 1. Keyboard Devices necessary conclusion from the given 2. Point and Draw Devices premises. 3. Digitizer Inductive – is generalizing from cases we 4. Data Scanning Devices have seen to infer information about cases we 5. Microphone have not seen. 6. Electronic cars Readers Abductive – reasons from a fact to the action common applications for electronic or state that caused it. visual displays are television sets or PROBLEM SOLVING computer monitors. Gestalt Theory - problem solving is both Standard Output Devices: productive and reproductive 1. Monitor Screens - productive problem solving involves insight 2. Printers and restructuring of the problem while 3. Plotters reproductive solving problem draws on 4. Projectors previous experiences. Problem Space Theory - problem has an Handwriting Recognition - also known as initial state and a goal state and people use handwritten text recognition, is the ability of the operators to move from the former to the a computer to receive and interpret latter. intelligible handwritten input from sources Analogy - is a cognitive process of such as paper documents, photographs, transferring information or meaning from a touch-screens and other devices. particular subject to another, or a linguistic The field of automated handwriting recognition has expression corresponding to such a process. achieved significant real world success in targeted done by mapping knowledge relating to a similar applications such as: known domain to the new problem – analogical address recognition on mail-pieces for mapping. sorting automation; PSYCHOLOGY AND THE DESIGN OF reading of courtesy and; INTERACTIVE SYSTEM: legal amounts on bank checks. In order to apply a psychological principle or result properly in design, the following must be Speech Recognition - also known as understood: automatic speech recognition (ASR), 1. the context where it fits in the field of computer speech recognition, or speech-to- psychology text, is a capability which enables a program 2. details of the actual experiment to process human speech into a written 3. measures used format. 4. subjects involved Some of the most commonly used methods: Guidelines - Human cognitive and perceptual Natural language processing (NLP). Area process cannot be all directly applied to of artificial intelligence which focuses on the design due to being partial and simplistic. interaction between humans and machines Models to support design - Psychological through language through speech and text. theory has led to the development of analytic Hidden markov models (HMM). Utilized as and predictive models of user behavior. sequence models within speech recognition,  assigning labels to each unit—i.e. words, Design - interference testing (e.g. engine syllables, sentences, etc.—in the sequence. assembly) N-grams. the simplest type of language Teleoperation of robots in dangerous model (LM), which assigns probabilities to (Chernobyl) or distant (Mars) locations sentences or phrases. Medical X-ray vision (e.g. ultrasound) Neural networks. Process training data by Remote surgery mimicking the interconnectivity of the human Psychotherapy (e.g. fear of heights) brain through layers of nodes. Interactive microscopy Speaker Diarization (SD). Algorithms DEVICES FOR VR AND 3D INTERACTION: identify and segment speech by speaker Cockpit and Virtual Controls - Commonly identity. This helps programs better used by helicopter and aircraft pilots distinguish individuals in a conversation and 3D Mouse - Rather than just moving the is frequently applied at call centers mouse on a tabletop, you can pick it up, move distinguishing customers and sales agents. it in three dimensions, rotate the mouse and tip it forward and backward. Voice-Activated Systems: Smart assistants Data Glove - consisting of a lycra glove with and voice-activated systems are becoming optical fibers laid along the fingers, it detects more sophisticated, allowing users to interact the joint angles of the fingers and thumb. with technology through conversational VR Helmets - The helmets or goggles worn interfaces, which are now integrated into in some VR systems have two purposes: (i) homes, cars, and public spaces. they display the 3D world to each eye and (ii) DISPLAY DEVICES: they allow the user’s head position to be Types of electronic displays: tracked. 1. Cathode-Ray Tube(CRT) - a technology Touchless Interaction - The Leap Motion which is used in traditional computer monitor Controller 2 is the ideal hardware to and television. experience hand tracking, which allows you 2. Color CRT Monitor to use your own hands in digital worlds. 3. Liquid crystal display(LCD) - The LCD Full-body tracking - Full body tracking in depends upon the light modulating properties virtual reality is made possible through the of liquid crystals. use of technological devices which are 4. Light Emitting Diode(LED) - a device attached to the feet and the hands of the user, which emits when current passes through it. It which enables the tracking of their position in is a semiconductor device. the space. 5. Direct View Storage Tubes(DVST) - used to VR Caves - It is an immersive virtual reality store the picture information as a charge environment where projectors are directed to distribution behind the phosphor-coated between three and six of the walls of a room- screen. sized cube. 6. Plasma Display - a type of flat panel display OTHER RECENT TECHNOLOGIES: which uses tiny plasma cells. It is also known Wearable Technology as the Gas-Discharge display. Smart Glasses, Watches, and Sensors: 7. 3D Display - also called stereoscope display Wearables continue to evolve with better technology. This technology is capable of sensors and user interfaces. bringing depth perception to the viewer. Ubiquitous Computing and IoT (Internet of VIRTUAL REALITY INTERACTION: Things) Common Application: Context-Aware Systems: IoT devices interact Flight simulators with each other to provide users with context- Architectural walk-throughs aware information.  Embedded Interfaces: Everyday objects are 4. movement becoming interactive through IoT, allowing Visual Channel - Human vision is a highly users to interact with their environment in complex activity with a range of physical and more intuitive ways. perceptual limitations, yet it is the primary Tangible User Interfaces (TUI) source of information for the average person. Physical Objects as Input Devices: TUIs THE HUMAN EYE allow users to interact with digital systems Cornea and lens - at the front of the eye using real-world physical objects. focus the light into a sharp image on the back Artificial Intelligence and Machine Learning of the eye, the retina. (AI/ML) Retina - is light sensitive and contains two Personalization: AI and ML are being used to types of photoreceptor: rods and cones. create more personalized user experiences by Rods - are highly sensitive to light and analyzin user behavior and preferences. therefore allow us to see under a low level of LIMITATIONS ON INTERACTIVE Illumination. However, they are unable to PERFORMANCE: resolve fine detail and are subject to light Computation bound. The system should be saturation. designed so that long delays are not in the Cones - are the second type of receptor in the middle of interaction and so that the user gets eye. They are less sensitive to light than the some idea of how the job is progressing. rods and can therefore tolerate more light. Storage channel bound. The speed of The retina also has specialized nerve cells memory access can interfere with interactive called ganglion cells. There are two types: performance. X-cells, which are concentrated in the fovea Graphics bound. The most common and are responsible for the early detection of bottleneck for many modern interfaces. It is pattern easy to underestimate the time taken to Y-cells which are more widely distributed in perform what appear to be simple interface the retina and are responsible for the early operations. detection of movement. Network Capacity. Most computers are VISUAL PERCEPTION linked by networks and this can mean using Perceiving size and depth. Visual angle is shared files on a remote machine. affected by both the size of the object and its distance from the eye. NETWORKED COMPUTING Perceiving brightness. Brightness is in fact a Computer systems in use today are much subjective reaction to levels of light. It is more powerful than they were a few years affected by luminance which is the amount of ago, which means that the standard computer light emitted by an object. on the desktop is capable of high- Perceiving color. Color is usually regarded performance interaction. as being made up of three components: hue, intensity and saturation. Hue is determined by the spectral wavelength THE HUMAN PERCEPTION: of the light. Blues have short wavelengths, Humans - are limited in their capacity to greens medium and reds long. process information. This has important Intensity is the brightness of the color implications for design. Saturation is the amount of whiteness in the Information is received and responses given via a color. number of input and output channels: Humans can perceive in the region of 7 million 1. visual channel different colors. 2. auditory channel READING 3. haptic channel There are several stages in the reading process:  A second aspect of haptic perception is kinesthesis: awareness of the position of the body and limbs. This is due to receptors in the joints. There are three types: 1. rapidly adapting, which respond when a limb is moved in a particular direction 2. slowly adapting, which respond to both AUDITORY CHANNEL movement and static position Hearing - The sense of hearing is often 3. positional receptors, which only respond considered secondary to sight and often when a limb is in a static position. underestimated in the amount of information MOVEMENT that can be received. Motor control is the way we move affects PROCESSING SOUND our interaction with computers. It has a number of characteristics which we can stimulus (of the question) is received differentiate: through the sensory receptors and transmitted Pitch is the frequency of the sound. A low to the brain. frequency produces a low pitch, a high Movement time is dependent largely on the frequency, a high pitch. physical characteristics of the subjects: their Loudness is proportional to the amplitude of age and fitness. the sound; the frequency remains constant. Reaction time varies according to the Timbre relates to the type of the sound: sensory channel through which the stimulus sounds may have the same pitch and loudness is received. but be made by different instruments and so A second measure of motor skill is accuracy and is vary in timbre. dependent on the task and the user. The human ear can hear frequencies from about 20 Speed and accuracy of movement are Hz to 15 kHz. It can distinguish frequency changes important considerations in the design of of less than 1.5 Hz a low frequencie but is less interactive systems. accurate at high frequencies. HUMAN MEMORY HAPTIC CHANNEL Information is stored in memory: Touch - The third and last of the senses that sensory memory to consider is touch or haptic perception. short-term (working) memory We receive stimuli through the skin. The skin long-term memory contains three types of sensory receptor: thermoreceptors respond to heat and cold nociceptors respond to intense pressure, heat and pain mechanoreceptors respond to pressure. There are two kinds of mechanoreceptor, which respond to different types of pressure. Rapidly adapting mechanoreceptors respond to immediate pressure as the skin is sensory memories act as buffers for stimuli indented. These receptors also react more received through the senses. quickly with increased pressure. However, they stop responding if continuous pressure is applied. Slowly adapting mechanoreceptors respond to continuously applied pressure.  1. Entry conditions. Conditions that must be satisfied for the script to be activated. 2. Result. Conditions that will be true after the script is terminated. 3. Props. Objects involved in the events described in the script. 4. Roles. Actions performed by particular It exists for each sensory channel: iconic memory participants. for visual stimuli, echoic memory for aural stimuli 5. Scenes. The sequences of events that occur. and haptic memory for touch. 6. Tracks. A variation on the general pattern Attention is the concentration of the mind on representing an alternative scenario. one out of a number of competing stimuli or There are three main activities related to long-term thoughts. memory: Short-term memory or working memory 1. Storage or remembering of information acts as a ‘scratch-pad’ for temporary recall of 2. Forgetting information. It can be accessed rapidly, in the 3. Information retrieval order of 70 ms. Decays rapidly, meaning that According to the study of Ebbinghaus , the amount information can only be held there learned was directly proportional to the amount of temporarily, in the order of 200 ms. time spent learning, which is also known as the Recency effect is where recall of the last total time hypothesis. words presented is better than recall of those Experiments by Baddeley and others, suggested in the middle. distribution of practice effect that learning time is short-term memory recall is damaged by most effective if it is distributed over time. interference of other information. Long-term memory - Main memory resource where we store factual information, experiential knowledge, procedural rules of behavior or everything we know. There are two types of long-term memory: episodic memory and semantic memory. Episodic memory represents our memory of events and experiences in a serial form. It is from this memory that we can reconstruct the actual events that took place at a given point in our lives. Semantic memory, on the other hand, is a structured record of facts, concepts and skills that we have acquired. The information in semantic memory is derived from that in our episodic memory, such that we can learn new facts or concepts from our experiences. Models on how to organize information into data structures. Frames and Scripts. Scripts attempt to model the representation of stereotypical knowledge about situations. A script comprises a number of elements, which, like slots, can be filled with appropriate information: