HCI notesHIP Human Information Processing 1. What is HIP 2. HIP in HCI 3. Predictive and Descriptive models 4. An alternative to the Cognitive Model 5. Conclusion 6. ReferencesHCI notes: Human Information Processing
1. What is HIP HUMAN + INFORMATION PROCESSING ≅ The computer is adopted as a metaphor of human cognitive functioning. how? people receive, store, integrate, retrieve and use information
1. primarily developed a theory of memory. HIP theory focused on the way people pay attention to the environment events, encodes information and related with already stored knowledge for learning, and how information is retrieval when needed. sensory working long term memory memory memory motor stimulus processor (sensory input) ■ Are responsible for ■ the memory buffer that holds ■ The mental storage transforming environmental input currently and recently system responsible for into neural impulses which the processed information, and the storing information on a Short Term Memory system can can manipulate that information relatively permanent process. as well. basis Motor Subsystem Perceptual Subsystem Cognitive Subsystem Analogous to Input Analogous to ROM device. Analogous to CPU memory where software is (keyboard or scanner, or stored voice recognition system)
1. sensory working memory memory PROCESSES ■ Pattern recognition. Process of granting meaning to the stimulus by comparing the entry with the known information. PERCEPTION ■ Bottom-up (data-driven). Physical characteristics of stimulus drive perception. The interpretation emerges from the data. ATTENTION ■ Top-down (schema-driven). Knowledge, expectations, or thoughts inﬂuence perception. Constructivism: we structure the world. A higher-level concept inﬂuences your interpretation of lower level sensory data. “We go "beyond the information given" constantly in our mental processes. We learn to add assumptions and supplemental information derived from past experience to the evidence of our senses, and that is how we make sense of our world.”(Jerome Bruner, Beyond the The "Rat-Man" of Bugelski Information Given, 1972) and Alampay (1961).
1. ■ Bottleneck models. Broadbents -and other attention models likeTreismans and Deutsch and Deutsch - are all bottleneck models because they predict we cannot consciously attend to all of our sensory input at the same time. ATTENTION This limited capacity for paying attention is therefore a bottleneck and the models each try to explain how the material that passes through the bottleneck is selected. Broadbentʼs (1958) Filter Model of Selective Attention Factors related with the ﬁlter: The number of input of information | The similarity of the input | The complexity of the input. ■ Controlled and Automatic processing. Controlled processes must be executed in series because they need attention. Autonomous processes do not need much attention so they can run in parallel with other processes. As a controlled task becomes habitual, eventually becomes automatic. Example: The stroop effect, It is very hard to disconnect an automatic process. The stroop effect
2. HIP in HCI HUMAN INFORMATION PROCESSOR MODEL “is a cognitive modeling method used to calculate how long it takes to perform a certain task” ■ Cognitive models come from cognitive science. Unlike behavioral models COGNITIVE (theories based on the analysis of stimuli and responses) cognitivism is based MODEL? on internal mental processes. E R INPUT OUTPUT ? ■ The origin of the cognitive sciences coincides with the emergence and development of computers. The operation of these machines serves as a metaphor for the researcher to explore the workings of internal cognitive processes.
2. why? ■ HIP models are used in HCI to predict how an interactive HCI HIP GOMS system can be used. ■ Inside the HIP the dominant model - and most used- is the GOMS, developed for Card, Moran & Newell in the 80s. GOMS is a theory of the cognitive skills involved in human-computer tasks. ■ HIP approach is broader than GOMS. HIP can be used to model more complex human behaviors like: Problem solving, Learning or group interaction. GOMS According to the GOMS, cognitive structure consist of 4 components: ■ Is a predictive model (related mainly to routine skills). Reduces user-computer interaction to its elementary actions (physical, cognitive or perceptual) G a set of goals ■ The method uses experimental time to O a set of operators calculate cognitive motor processing time. M a set of methods for achieving the goals ■ Allows a system designer to predict the PERFORMANCE with respect to time it takes S a set of selection rules for chosing a person to complete a task without among competing methods. performing experiments.
3. PREDICTIVE AND DESCRIPTIVE MODELS Predictive Descriptive models models [quantitative] [qualitative] Key-action Hick-Hyman Law Model Fitt’s law GOMS Buxton’s 3-states model Keystroke-level Guiard’s model model of bimanual control *PM. Refers to a mathematical model that can *DM. Refers to a mathematical model that accurately predict future outcomes. describes historical events, and the presumed or real relationship between elements that created
3. Predictive Descriptive models models ■ Also engineering models or performance models. ■ Provide a framework or context for thinking about or describing a problem or situation. ■ In HCI, allow metrics of human performance to be determined analytically without experiments. Often the framework is little more than a verbal or graphic articulation of categories or identiﬁable ■ Predictions are a priori: allow a design scenario to features in an interface. Nevertheless, the simple be explored hypothetically. possession of such a framework arms the designer with a tool for studying and thinking about the user-interaction EXPERIENCE. Example: Keystroke-level model Example: Key-action Model TEXECTUTE= tK + tP + tH + tD + tM + tR (motor-control operators) K= key stroking | P= pointing | H= homing | D= drawing. Symbol keys: deliver graphic symbols ( letters, numbers, or punctuation) Executive keys: invoke actions in the application or at the system level or meta M= metal operator level. (examples include ENTER, F1 or ESC) R= System-response operator Modiﬁer keys: Set up a condition necessary to modify the effect of a subsequently pressed key. (example SHIFT or ALT)
4. Alternatives to Cognitive Models. Activity Theory ALTERNATIVES TO COGNITIVE MODELS Why alternatives are necessary? There is some evidence that the cognitive approach may be limited for HCI. The limitation of modelling methods to support the design process, may be due to their lack of taking context into account. ■ It does not provide an appropriate conceptual basis for ■ Humans are not processing the information input from studies of computer use in its social, organizational and the environment - they are actively picking up the cultural contexts. information that is relevant in the context of their current needs and goals. It is control of this ■ The method has a number of defects such as information pickup where the focus of HCI should be reducing problem solving and judgement to mere rule Gibson, 1966. following, ignoring informal communication, underestimating of errors, giving no help to analysing ■ Difference in the information processes of computers work organisation, etc and human mental decision processes.(Rasmussen) In some contexts, HIP model is not completely satisfactory. Activity Theory (AT) has been a recognized conceptual framework in HCI and related disciplines.
4. Cognitive Science represent two different approaches Activity theory to the study of cognitive processes Activity Theory ■ Develop by Vygotsky (1920-30) Is an alternate psychological approach (Russian). A more broad based and durable framework for understanding ‘humans His basic idea was that human activity is interacting with computers’. mediated by cultural signs: words and tools, which causes changes in a persons activity, ■ The subject and the object are viewed as poles of a and thus its mental reﬂection. system of activity, which emphasises the active nature of humans. ■ Takes a broader view of the technisation of human operations and places HCI within this wider framework. ■ Emphasises the contextuality of computer use. The contextual model of Activity. ■ (Respect to Cognitive Models) Activity Theory attacks its theoretical basis: the principle of cognitive identity between human thinking and computer simulation
4. Cognitive Activity Science theory theory Information Processing Loop Tool-mediation The main difference between the two theories (applied to HCI) is the point of view of the problem, or “clipping” (constraints) that makes the reality. The Tool Mediation perspective suggest a different structure from the Information Processing Loop. ■ In HPI model the components of the ■ The computer is just another tool that mediates the interaction of human beings structure is limited to two entities: with the environment. ■ There are 2 interfaces: The human- computer a n d t h e c o m p u t e r- USER COMPUTER environment. Information Processing Loop: USER TOOL OBJECT The output from the human being, enters the computers input, and visa versa.
5. CONCLUSION @ computer internet social software (social information systems) Thanks to the internet and social software boom (and many others), it seems that we have taken a step higher in the scale of complexity described by Modridge. anthropometrics physiology psychology sociology anthropology ecology simplest level most complexThe sizes of people, for the The way the body works, The way the mind works, The way people relate to The human need to understand thedesign of physical objects for the design of physical for the design of human- one another, for the design condition, for global issues that will affect the man-machine systems computer interactions of connected systems design. environmental (cultural variations ) condition of our planet as well as the interconnected social and economic systems that we need to sustain.
■ Increasing complexity. ■ Need to incorporate more complex and wider models to help us predict behavior in dynamic contexts (as in social networks). ■ Need to work with multidisciplinary teams (Psychologists. Sociologists... ) ■ Need to incorporate frameworks beyond usability (Funology, emotional design, etc...) thanks!persuability design affective emotionalfunology interactionshuman centered design
6. REFERENCES Aboulaﬁa, Annette; Gould, Edward; Spyrou, Thomas. Activity Theory vs Cognitive Science in the Study of Human-Computer Interaction. Carroll, John M. (2003) HCI models, theories, and frameworks: toward a multidisciplinary science. http://books.google.com/books?id=gR3Imgvr5dYC&pg=PA30&lpg=PA30&dq=map+of+HCI +models&source=bl&ots=C86ciZWVKk&sig=v7YhY8JEdclkNY4goyb5Nc0u0h4&hl=en&ei=LMb2S- zzNabWmgOS48zHAg&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBYQ6AEwAA#v=onepage&q=map%20of%20HCI%20models&f=false. Gibson J. J. (1966) The Senses Considered as Perseptual Systems, Boston, Houghton Mifﬂin. Kaptelini, Victor. Activity Theory: Implications for Human-Computer Interaction. Moggridge, Bill (2007) Designing Interactions. Boston, MIT Press. Mwanza,Daisy; Bertelsen, Olav W. (2003) Methods for applying Activity Theory to HCI Design. Norman, Donald (1998) The Invisible Computer. Boston, MIT Press.