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Situated actions as ... An alternative view of human action An alternative account of the relation of plans to situated actions The user as a resourceful person Lucy Suchman, 1987 Anthropologist, – Philosophy ( Dreyfus) – Phenomenology (Merleau- Ponty ) – Symbolic Interactionism (Garfinkel, Goffman) Interested in producing an adequate base of descriptions of human practices – What’s happens when someone does something ? Suchman’s central concern The relation between observable behaviour and the processes not available to direct observation, that make behaviour meaningful, What constitutes purposeful actions and how is it understood ? About the European and the Trukese navigator The European navigator exemplifies the cognitive science model of purposeful action The Trukese navigator exemplifies the situated action perspective The view of action exemplified by the European navigator is being reified in the design of intelligent machines – The logical form of plans makes them attractive for the purpose of constructing a computational model of action The view that purposeful action is determined by plans, is deeply rooted in the Western human sciences as the correct model of the rational actor Two alternative views of action i) The planning view The organization and significance of human action is located in underlying plans (artificial intelligence) ii) The situated actions view The prescriptive significance of intentions for situated actions is inherently vague (ethnomethodology) The planning view Plans are prerequisite to and prescribe actions at every level of detail Mutual intelligibility is a matter of reciprocal recognizability of our plans The planning view has to do with : – The planning model (Miller, Galanter and Pribram, 1960) – Speech act theory (Searle, 1969 ) – The idea of shared background knowledge as the common resource that is given (Durkheim, 1938) The planning model in cognitive science . Plans are a sequence of actions designed to accomplish a preconceived end, Action is a form of problem solving and are described in terms of preconditions and their consequences, Goals define the actor’s relationship to the situation of action, The situation is those conditions that obstruct or advance the actor’s progress toward his/her goal Searle’s speech act theory : some initial guidelines for computational models of communication The hypothesis is that people maintain as part of their models of the world, symbolic descriptions of the world models of the people Speech act are regarded as actions whose effects are primarily on the models that speakers and hearers maintain of each other Background knowledge Gumperz shows that an action significance seems to lie as much in what it presupposes and implies about its situation He questions the view that background assumptions are part of the actor’s mental state prior of action The background knowledge is not taken for granted Significance depends on a particular context that is always open-endlessness Common sense are resources According to cognitive science The mind is viewed as an abstractable structure implementable in any number of possible physical substrates – intelligence is only incidentally embodied in the neurobiology of the human brain, – what is essential about intelligence can be abstracted from that particular substrate and embodied in an unknown range of alternative forms Artificial Intelligence People act on the basis of symbolic representation, a kind of cognitive code, Cognition is not just potentially like computation it literally is computational The view that intelligence is the manipulation of symbols finds practical implementation both in so called expert systems and industrial robots What is a plan ? ”[…] When we speak of a plan the term will refer to a hierarchy of instructions A plan is any hierarchical process in the organism that can control the order in which a sequence of operations is to be performed. A plan is for an organism essentially the same as a program for a computer […]” Miller, Galanter and Pribram, 1960 The situated action view Focus on practice as different to the study of the formal cognitive properties of artifacts Unit of analysis is the activity of persons-acting in setting The prescriptive significance of intentions for situated action is inherently vague, Improvisatory nature of human action Human action is contingent Situated action view Every course of action depends in essential ways upon its material and social circumstances 1- Plans are representations of situated actions 2- In the course of situated action representation occurs where there is a breakdown 3-The objectivity of the situation of our action is achieved rather than given 4- Central resource for achieving the objectivity of situations is language 5-Mutual intelligibility is achieved in every occasion of interaction The problem of human-machine communication ”Expert help system” – a computer-based system attached to a photocopier, intended to instruct the user The design objective – to provide timely and relevant information to the user regarding the operation of the copier The system must recognize the action of the user The expert help system identifies ... the user’s purposes with a job specification and the specification invokes a associated plan the plan is ascribed to the user as a basis for interpreting her actions the plan is conveyed in the form of instructions for a step-wise procedure the design assumes that there is correspondence of the system’s plan to the user’s purposes that enables the interaction Which are the consequences of taking a statement of intent and an ascribed plan as grounds for the interpretation of situated action ? Troubles for the resourceful user... Plans and states instructions machine actions Situated inquiries Problems of understanding due to the disparity of their respective resources The system’s resources The machine has access only to a very small subset of user action – i.e.Doors being opened and closed, buttons being pushed, papers trays being filled… The machine is watching the user’s actions through a very small key hole, mapping what it saw back onto a pre specified template of possible interpretations The user’s resources Human interaction succeeds due not simply to the abilities to construct meaningfulness but to the possibility of mutually constituting intelligibility – i.e.Detection and repair of misunderstandings Interactive program exploits certain characteristics of human conversation Language of interactivity and the dynamics of computational artifacts obscure enduring asymmetries that users discover in practice Speech acts tell us nothing further about the significance A : Are you going to be here for ten minutes ? B: Go ahead and take your break. Take longer if you want A: I’ll just be outside on the porch. Call me if you need me B: Ok, Don’t worry (Gumperz, 1982) How B arrives at the right inference ? Indexicality of language Efficiency of language lies in : – expressions with conventional meanings – its relationship to circumstances (conditional meanings) – The indexicality of instructions means that an instruction ’s significance with respect to action does not inhere in the instruction but must be found in the situation of use The mutual intelligibility of actions Within the normative paradigm actors share a system of culturally established symbols and meanings The stability of the social world is not due to an eternal structure but to situated actions that create and sustain shared understanding on specific situations of interaction Relation of plans to situated actions In the planning model of human interaction, – plans are mental constructs, abstractions over action, representations of situated actions Plans do not take sufficient account of the situatedness of most social behaviour The planning model confuses plans with situated actions Alternative account of the relation of plans to situated actions The foundation of action is not plans but local interactions with the environment The function of plans is to orient or position us, to exploit some contingencies of our environment and to avoid others – plans are weak resources Critiques Confined to the analysis of actions and operations Slightly behaviouristic undercurrent in that it is the subject’s reaction to the environment that determines action Primacy of the situation What constitutes a situation is defined by the researcher Resourceful user or …. ?