Systems Thinking in Practice

Applications of the Event Analysis of Systemic Teamwork Method

Neville A. Stanton,Paul Salmon,Guy H. Walker

• Éditeur: CRC Press
• Année: 2018
• ISBN:
  9781351598835
• Édition: 1
• Sujet: Technologie et ingénierie
• Sous-sujet: Ingénierie

This book presents the latest developments of Systems Thinking in Practice to the analysis and design of complex sociotechnical systems. The Event Analysis of Systemic Teamwork (EAST) method is applied to micro, meso and macro systems. Written by experts in the field, this text covers a diverse range of domains, including: automation, aviation, energy grid distribution, military command and control, road and rail transportation, sports, and urban planning. Extensions to the EAST method are presented along with future directions for the approach.

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• Illustrates a contemporary review of the status of Distributed Cognition (DCOG)

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• Presents examples of the application of Event Analysis of Systemic Teamwork (EAST) method

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• Presents examples of the application of Event Analysis of Systemic Teamwork (EAST) method

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• Discusses the metrics for the examination of social, task, and information networks

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• Provides comparison of alternative networks with implications for design of DCOG in systems

Section II

Applications of EAST

2	EAST in Air Traffic Control

With Chris Baber, Linda Wells, Huw Gibson and Daniel P. Jenkins

INTRODUCTION

COMMAND AND CONTROL

In command and control scenarios, there is a common goal (comprising interacting sub-goals), there are multiple individuals who need to communicate and coordinate with each other in order to attain these goals and, increasingly, there are ever more complex ways of facilitating this process with technology. Command and control, at the most generic level, can be viewed as a form of management infrastructure for planning and organisation (Harris and White 1987). It involves the exercise of authority and direction by properly designated individual(s) over assigned resources, as well as planning, directing, coordinating and controlling how those resources are deployed (Builder et al. 1999). ‘Command’ can be viewed as the definition of overall system objectives or goals, whereas ‘control’ is the management of process and activities that lead to the achievement of these objectives (or compensate for changes in the environment that hinder their achievement). Many contemporary sociotechnical systems involve authority, planning, directing and coordinating and can be considered as forms of command and control. Air Traffic Control (ATC) is one example.

DISTRIBUTED COGNITION

From a distributed cognition perspective (e.g. Hutchins 1995a), the task of ATC can be viewed as a form of ‘“computation” to maintain separation between aircraft in a region of airspace’ (Fields et al. 1998, p. 86). It is further argued that the computations do not reside solely in the heads of individual controllers; instead, they are distributed across the entire ATC system, comprising numerous controllers, teams and technical artefacts. The essence of distributed cognition is on ‘how [these computations] transcend the boundaries of the individual actor’ (Rogers 1997, p. 1; Hutchins 1995a; Hollan et al. 2000).

The language of representational states is used to describe the visible and external manifestations of various ‘environmental contributions’ to the total system (Rogers and Ellis 1994; Fields et al. 1998). Representational states subsume the full range of observable interactions between people and artefacts, as well as the resulting states (and state changes) that arise from the various ‘computations to maintain separation between aircraft’. For example, an observable interaction might be a controller issuing an instruction to an aircraft. The resulting state might be a corresponding change in the aircraft’s representation on the radar display.

In command and control situations, these computations and representational states interact. A change in representational state leads to further computations, further representational states and further computations. But whilst these simple low-level mechanisms can be multiplied in simple ways to form the total ATC system, the high-level function, the system’s aggregate behaviour, can be highly complex and adaptive (Chalmers 1990). Phenomena ‘wherein complex, interesting high-level function is produced as a result of combining simple low-level mechanisms in simple ways’ are referred to as ‘emergence’ (Chalmers 1990, p. 2). A key emergent property of ATC is the so-called ‘picture’ or, in ergonomics parlance, situational awareness (SA).

DISTRIBUTED SITUATION AWARENESS

The ability to sense changes in representational states, understand them and then perform some kind of computation based on them not only describes the essence of distributed cognition but also that of SA. At an individual level, SA is about the psychological processes, and information in working memory required, for developing ‘the picture’ (e.g. Endsley 1995; Bell and Lyon 2000). The controller’s picture is not the same as the radar display; it does not arise solely from any one physical or human component but from the interaction of many such components. It arises both from the parts of the ATC task that have been overtly designed (i.e. radar displays and other prescribed forms of communication) and those parts of the task that have not been overtly designed (i.e. the clicking of new flight data strips, which informs controllers that a new aircraft is about to enter their sector). Because the picture, or SA, arises from these myriad individual components, yet its totality cannot be predicted solely from any one of them individually, it can be referred to as emergent.

Individualistic approaches to SA dominate ergonomics, but whilst they may be appropriate for tasks that are performed by individuals in isolation, few complex tasks are performed entirely independently of others (Perry 2003). In systems terms, SA is what helps entire sociotechnical systems such as ATC to be orientated towards and ‘tightly coupled to the dynamics of the environment’ (Moray 2004, p. 4). A distributed cognition perspective applied to command and control scenarios requires a shift from traditional notions of SA that focus on the individual (e.g. Endsley 1995) to those that focus on the system (e.g. Sandom 2001; Gorman et al. 2006; Salmon et al. 2008). At face value, the response to this might be the concept of team SA (e.g. Salas et al. 1995; Perla et al. 2000) but even here there are problems. ‘The degree to which every team member possesses the SA required for his or her responsibilities’ (Endsley 1995, p. 39) runs into difficulties when confronted with the twin concepts of ‘overlapping SA’ (i.e. portions of SA that are identically shared between people, normally represented as a Venn diagram) and ‘compatible SA’ (i.e. that which is ‘not’ overlapping between two or more people, but which fits together like a jigsaw; Salmon et al. 2008). The fundamental problem stems from a tacit assumption that the ‘situation’ can be defined as a single, objective, external reality and that the goal of the people operating within the situation is to respond to all features appropriately. This is problematic on three counts:

1.There are many aspects of command and control scenarios that require the individual to make judgements and interpretations (so the assumption of the ‘objective reality’ of a situation is not always valid).

2.There are multiple sub-goals and multiple views of the situation (so the idea of a single reality is not valid either).

3.Different agents within the system use different representational states to inform and support their work, so the notion that there can be a single view of the situation (as opposed to several interlocking views) is also not easily supported.

One way to resolve the mismatch between mainstream thinking in SA and distributed cognition of the sort encountered in complex systems, such as ATC, is to consider one of the relatively invariant properties of it: information. According to Bell and Lyon (2000): ‘all aspects of momentary SA are eventually reducible to some form of [. . .] information in working memory’ (p. 42). Information, in the SA sense, refers to what, in distributed cognition language, are called representational states. The question to ask is whether ‘working memory’ is the only place where such states can be represented. Distributed cognition would suggest not. It suggests that non-human artefacts can create, manage and share such states (to some extent at least), meaning that the technical aspects of a sociotechnical system will be contributing to the exchange of representational states too. The totality of this will be a form of systems level awareness that is not traceable to any one individual and is not consistent with a distributed cognition view of the world, nor resides exclusively in the minds of humans. Thus, not only is the individual-level ATC ‘picture’ emergent, so too is the systems level ‘picture’.

Another consideration is that representational states can be promulgated around the system with very little in the way of overt communication. One of the great strengths of expert operators is their ability to chunk information, to abstract and pattern match, to develop a high level of awarene...