Situational awareness
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[edit] Situation Awareness (SA)
Situation Awareness is a human factors term which of late has become something of a buzzword. There is more to situational awareness than simply being 'aware of your situation'. Despite its popularity and ubiquity there is much debate within the scientific literature about what SA is, how it works and whether we need such a concept at all.
An established definition of Situation Awareness is provided by Endsley (1988). She describes it as comprising three levels: level 1 perception of elements, level 2, comprehending what those elements mean and level 3, using that understanding to project future states.
This definition is tractable and extremely popular, to the extent that the notion of SA has become almost synonymous with it. Unfortunately, this tends to conceal a vibrant debate in the literature. So, starting from scratch SA can be described variously as knowing and understanding what is going on around you and predicting how things will change, or, in other words, "being coupled to the dynamics of your environment" (Moray, 2004).
Fundamentally, SA is an informational concept, in fact some would say that all SA is eventually reducible to information in working memory (e.g. Bell & Lyon, 2000). But its more than this and needs to take into account how experts (and you are an expert in something, whether its driving a car or flying a plane) perceive, structure and use knowledge that you gain from your immediate (and presumably changing) environment.
SA relies on information in the context (an objective state of the world) and a state of knowledge built on that information (a subjective state). Knowledge can be defined as a “body of information possessed by a person” yet it is also “more than a simple compendium of dispositions to respond or a collection of conditioned responses” (Reber, 1995, p. 401). From an information processing viewpoint, knowledge appears to fall along a continuum. Knowledge can be a discrete instance of perceived information, akin to Gibson’s (1979) ideas of direct perception, and, therefore, would indeed have a direct analogue to an objectively manifest physical stimuli. Knowledge can, at the other end of the continuum, be an entity that arises, or emerges, from the complex interplay of various mental processes, for which a publicly observable physical stimuli need not be present. In other words, knowledge can be created by the simple perception of elements in the environment (Level 1 SA; Endsley, 1995) as well as comprehending what those elements mean (Level 2 SA; Endesley, 1995). Because all perceptual experience is hypothetical a person develops a mental theory of the world that helps to conceptualise how elements are comprehended, that is to say ‘explained’, and how future states can be predicted (Level 3 SA; Endsley, 1995).
[edit] Process
The process of acquiring and maintaining SA, which Endesley (1995) refers to as Situational 'Assessment', subsumes a panoply of mental operations and structures. As such, some authors suggest that SA is not really a psychological construct at all (in the way that, for example, Short Term Memory is) and that SA “should be viewed as a label for a variety of cognitive processing activities that are critical to dynamic, event driven and multi-task fields of practice” (Sarter & Woods, 1995, p. 16; Patrick & James, 2004). Quite frequently the term mental model is used as a description either of what SA is (a state of knowledge) or how it is acquired (a process). Although appealing, the term mental model is itself highly contentious, not least because one could extend the argument and replace SA with the term 'dynamic mental model' or similar term. A whole range of other rather general concepts like memory, attention, perceptual processes and so forth have been implicated in the acquisition and maintenance of SA but there is, theoretically at least, still no definite answer as to the 'mechanisms' or 'process' of SA. What we can say is related to the idea of constructivism. In other words, people play a large part in creating the situation from which they develop their awareness. As Smith & Hancock (1995) put it, SA can be viewed as “a generative process of knowledge creation” (p. 142) in which “[…] the environment informs the agent, modifying its knowledge. Knowledge directs the agent’s activity in the environment. That activity samples and perhaps anticipates or alters the environment, which in turn informs the agent” (Smith & Hancock, 1995, p. 142) and so on.
[edit] Product
SA can also, perhaps more usefully, be regarded as a product. That is, less concerned with the processes of SA acquisition and rather more its content. This, according to Endesley (1995), is Situation Awareness proper. Both Endesley (1995) and Gugerty (1997) speak of ‘knowledge states’ as representative of the ‘product’ of SA. Knowledge states represent the way in which situations are experienced, a so-called ‘situation focus’. This is more “concerned with the mapping of the relevant information in the situation onto a mental representation of that information within the [driver]” (Rousseau, Tremblay & Breton, 2004, p. 5). This viewpoint conveys a rather normative flavour to much of the extant work on SA (e.g. SA measurement methods such as SAGAT; Endesly, 1988) that looks for discrepancies between the ‘situation’ and the person's ‘awareness’. Despite the appeal of such a view it is conceivable that good ‘awareness’ can be achieved not just by correspondence between an objective state of the world and its mental analogue, but also by the following:
Parts and Relations. The mappings that exist between different perspectives on a situation; in other words, to see connections between situational elements in addition to the elements themselves (e.g. Flach, Mulder & Paassen, 2004). In other words, the sum of situational knowledge may not be equal to its parts.
Abstraction. The way in which information and ‘awareness’ can be chunked into new functional units (thereby forming entities at higher, more implicit levels of abstraction) in order to develop a ‘mental theory’ of the world (Gugerty, 1997; Banbury, Croft, Macken & Jones, 2004; Bryant, Lichacz, Hollands & Baranski, 2004; Chase & Simon, 1973; Gobet, 1998). The term mental theory is a general concept (different from the hotly debated connotations of the term 'mental model') that reflects the “hypothetical nature of perceptual experience” (Bryant et al., 2004, p.110). A mental theory reflects the fact that ‘what is in the persons head’ (so to speak) is, arguably, “a representation that mirrors, duplicates, imitates or in some way illustrates a pattern of relationships observed in data or in nature […]”, “a characterisation of a process […]” that is able to provide “explanations for all attendant facts” (Reber, 1995; p. 465, 793). In other words, the mental theory might not look anything like the actual situation, yet it enables the person to function perfectly within it.
Parsimony. A good theory, and there is little reason to suppose that mental processes do not adhere to similar principles (e.g. Gobet, 1998; Chase & Simon, 1973), is one that aims to reduce complexity; the better the theory or model is, the more parsimonious it is likely to be. The principle of parsimony would actually require the 'products' of SA to be at a higher probably more implicit level of abstraction. Driving Without Attention Mode (DWAM; Kerr, 1991; May & Gale, 1998) seems to be a case in point. DWAM is an extreme example of ‘implicit SA’. It is an event that is characterised by a car driver not being able to recall how they arrived at a destination yet it is clearly the case that there must have been a functioning mental theory of the driving context, and concomitant SA, in order for them to have arrived safely at all (despite a lack of ability to explicitly describe ‘how’). In other words, the best mental theories, those developed by experts at a particular task, might be the ones that cannot be (easily) described or verbalised.
[edit] References
Banbury, S. P., Croft, D. G., Macken, W. J. & Jones, D. M. (2004). A cognitive streaming account of situation awareness. In S. Banbury & S. Tremblay (Eds) A cognitive approach to situation awareness: theory and application. (Ashgate: Aldershot).
Bell, H. H, and Lyon, D. R. 2000, Using observer ratings to assess situation awareness, In M. R. Endsley (Ed) Situation awareness analysis and measurement. (Mahwah, NJ: Laurence Earlbaum Associates).
Bryant, D. J., Lichacz, F. M. J., Hollands, J. G. & Baranski, J. V. (2004). Modeling situation awareness in an organisational context : Military command and control. In S. Banbury & S. Tremblay (Eds) A cognitive approach to situation awareness: theory and application. (Ashgate: Aldershot).
Chase, W. G. & Simon, H. A.(1973) Perception in chess. Cognitive Psychology, 4 55-81.
Endsley, M. R. (1995) "Toward a theory of situation awareness in dynamic systems". Human Factors, 37(1), 32–64.
Endsley, M. R. 1988, Situation awareness global assessment technique (SAGAT). Proceedings of the National Aerospace and Electronics Conference (NAECON). (New York: IEEE), 789-795.
Flach, J., Mulder, M. & Paassen, M. M. (2004). The concept of the situation in psychology. In S. Banbury & S. Tremblay (Eds) A cognitive approach to situation awareness: theory and application. (Ashgate: Aldershot).
Gibson, J. J. (1979). The ecological approach to visual perception. Houghton-Mifflin: Boston.
Gobet, F. (1998). Expert memory: a comparison of four theories. Cognition, 66, 115-152.
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Sarter, N. B. & Woods, D. D. (1991). How in the world did I ever get into that mode: Mode error and awareness in supervisory control. Human Factors, 37(1), 5-19.
Smith, K., & Hancock, P. A., (1995). Situation awareness is adaptive, externally directed consciousness. Human Factors, 37, (1), 137-148.
Stanton, N. A., Salmon, P., Walker, G. H., Baber, C. & Jenkins, D. (2005). Human Factors Methods: A Practical Guide for Engineering and Design. Aldershot: Ashgate.
Stanton, N. A., Chambers, P. R. G. & Piggott, J. (2001). Situational awareness and safety. Safety Science.
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