Situation Awareness A MODEL OF SITUATION AWARENESS Definitions

Situation Awareness A MODEL OF SITUATION AWARENESS Definitions and Terminology • • • Situation Awareness, as a state of knowledge, from the processes (situation assessment) used to achieve that state not encompass all of a person’s knowledge but only that portion pertaining to the state of a dynamic environment explicitly recognized as a construct separate from decision making and performance separated from others that may influence it – attention, working memory, workload, and stress knowing what is going on The perception of the elements in the environment within a volume of time and space (Level 1 SA), the comprehension of their meaning (Level 2 SA), and the projection of their status in the near future (Level 3 SA) Link to Decision Making • • situation parameters determines an effective problem-solving strategy adoption of an appropriate mental model, leading to the selection of problem-solving strategies Link to Performance • poor performance with incomplete or inaccurate SA USER INTERFACE LABORATORY

Situation Awareness HUMAN PROPERTIES AFFECTING AND UNDERLYING SA Attention • • • Preattentive Processing • • Major limit on SA direct attention for not only perceiving & processing the cues attended to but also the later stages of DM & response execution information sampling to avoid limited attentional capacity – in rapid sequence following a pattern from LTM, WM to modify attention deployment multiple resource theory automaticity spatial proximity, color, simple shapes, or movement, providing cues for further focalized attention to achieve perception cue salience Perception • • one’s preconception or expectations (the characteristics, form, and location of info) – speed & accuracy of the perception LTM – classifying perceived info into known categories or mental representations in the perception process (Level 1 SA) Working Memory • • Level 2 & 3 SA occur in WM main bottleneck for SA (novice, novel situation) LTM Schemata • coherent framework for understanding info, encompassing highly complex system components, states, & functioning • Much of the details of situations are lost but the info became more coherent & organized for storage, retrieval, and further processing • Script – a special type of schemata – sequences of appropriate actions for different types of task performance Mental Model • Rouse & Morris (1985) – Generate descriptions of system purpose & form, explanations of system functioning & observed system states, & prediction of future states ü experts will develop MM in a shift from representational to abstract codes ü Complex schemata to model the behavior of systems Situational Model (situation model, situation awareness) • Van. Dijk & Kintsch (1983), Roschelle & Greeno (1987) ü schema depicting the current state of the system model (schemata in memory that depict prototypical situations or states of the system model) ü the single-step recognition-primed decision making A well-developed mental model provides a. Knowledge of the relevant elements in directing attention and classifying info in the perception process b. A means of integrating the elements to form an understanding of their meaning (Level 2 SA) c. A mechanism for projecting future states (Level 3 SA) Automaticity • • • Development (Schemata and mental models) • training and experience • an individual will learn (Holland et al. , 1986) a. categorization function to map from objects in the real world to a representative category in their mental model b. model transition functions that describe how objects in the model will change over time Two more features to recognized attributes of SA 1. Default information – may be used to predict system performance or can be used if exact current values are not known 2. confidence level – the degree of uncertainty regarding the mapping of world information to the internal model and the projections based on the model • • fast, autonomous, effortless, and unavailable to conscious awareness in that it can occur without attention (Logan, 1988) can benefit SA by providing a mechanism for overcoming limited attention capacity Logan (1988) – through a direct-access, singlestep retrieval of actions to be performed from memory Level 1 Sa script from memory Reason (1984) – a minimum level of attention is required for all activity, even automatic processes Major implications Good performance with minimal attention allocation Significant difficulty in accurately reporting on the internal model and related key environmental features Unreliability and inaccuracy of reporting on processes after the fact USER INTERFACE LABORATORY

Situation Awareness Goals • • • ü • SA is fundamentally linked with a person’s goals The basis for most decision making in dynamic environment Top-down decision process a person’s goals and plans direct which aspects of the environment are attended to in the development of SA integrated and interpreted to form Level 2 SA bottom-up processing Salient cues will activate appropriate actions & plans related to the role of mental models and schemata USER INTERFACE LABORATORY

Situation Awareness Stress TASK AND SYSTEM FACTORS • System Design • • the first external issue influencing SA, is the degree to which the system acquires the needed info from the environment the second major issue involves the display interface for providing that info to the operator Errors in SA • incomplete SA – knowledge of only some of the elements • inaccurate SA – erroneous knowledge concerning the value of some elements • • • 1. 2. 3. 4. Interface Design Level 2 SA • inability to properly integrate or comprehend the meaning of perceived data • misreading of cues ü no mental model necessary for properly comprehending and integrating all of the incoming data ü incorrectly select the wrong model from memory ü with the wrong mental model, a representational error may occur 1. incorrect model may be select 3 d because of representativeness and availability biases 2. No model exists at all – Level 2 SA must be developed in WM • 1. 3. Level 3 SA • Level 3 SA may be lacking or incorrect • difficult to project future dynamics without a highly developed 7. mental model • • Workload • Level 1 SA • simply fail to perceive certain info (incomplete SA) 1. From a lack of detectability or discriminability for the signal in 2. • • • ERRORS IN SA question From a failure of the system design to make the info available to the operator human limitations in sampling, attention, and attention sharing attentional narrowing • physical stressors – noise, vibration, heat/ cold, lighting, atmospheric conditions, drugs, boredom or fatigue, and cyclical changes social psychological stressors – fear or anxiety, uncertainty, importance or consequences of events, aspects of task affecting monetary gain, self-esteem, prestige, job advancement or loss, mental load, and time pressure Mandler (1982) – are effective to the extent that they are perceived as dangerous or threatening Cognitive tunnel vision (attentional narrowing) premature closure – considering less info and attending more to negative info the early stage of the decision-making process (Level 1) through the decrement in WM capacity and retrieval 2. 3. 4. 5. 6. 8. mental workload, level of SA provided due to the limited attention and WM, displays provide info that is processed and integrated in terms of level 2 & 3 SA the degree to which info is presented in terms of operator’s major goals Critical cues for activating schemata & MM need to be determined and made salient Both top-down and bottom-up processing Global SA Filtering out extraneous info (not related to SA needs) & reduction of data (by processing and integrating lowlevel data to arrive at SA requirements) system-generated support for projecting future events & states directly benefit Level 3 SA System designs that support parallel processing independence between SA and workload Low SA with low workload – little idea of what’s going on, inattentiveness, vigilance problems, low motivation Low SA with high workload – SA may suffer, erroneous or incomplete perception & integration of info High SA with low workload – easy to process (an ideal state) High SA with high workload – working hard but successful in achieving an accurate and complete picture of the situation Complexity • negatively affect operator workload and SA Automation fails when (a) A loss of vigilance and increase in complacency (b) A shift from an active info processor to a passive info recipient (c) A lot of or change in the type of feedback provided to operators • SA decrement accompanying automation of a cognitive task that was greater under full automation than it was under various levels of partial automation USER INTERFACE LABORATORY