ABSTRACT While emergency response actions are known to range from conventional to improvised, less is known about the thinking processes that underlie these actions. This paper presents a statistical analysis of cognition and behaviour... more
ABSTRACT While emergency response actions are known to range from conventional to improvised, less is known about the thinking processes that underlie these actions. This paper presents a statistical analysis of cognition and behaviour reported by police personnel who responded to two significant US disasters: the 1995 bombing of the Murrah Building in Oklahoma City and the 2001 attack on the World Trade Center in New York City. The results suggest the prominence of conventional behaviour coupled with cognitive processes closely tied to recognition, and of improvised behaviours that are linked to more explicit reasoning processes. The results underscore the value of exploring cognitive foundations of both conventional and improvised behaviours to enrich understanding of human response to disaster.
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ABSTRACT This work describes a novel method for allocating entities to routes in a closed queueing network to maximize system throughput. Results are presented which compare this method with known prior work and known optimal solutions to... more
ABSTRACT This work describes a novel method for allocating entities to routes in a closed queueing network to maximize system throughput. Results are presented which compare this method with known prior work and known optimal solutions to provide an empirical optimality gap. Further, because the system of interest, debris removal following natural disasters, is under the control of rational agents, optimality conditions are derived in order to determine to efficacy of a flat market context in inducing optimal behavior.
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ABSTRACT This work investigates the effect of market structure on the performance of actors who dispatch resources in network-based organizations. As digital tracking of these actors increases in scope and specificity, it is becoming... more
ABSTRACT This work investigates the effect of market structure on the performance of actors who dispatch resources in network-based organizations. As digital tracking of these actors increases in scope and specificity, it is becoming feasible to extract computational models of dispatcher decision making which can be used to simulate market influences on these decisions. This work presents (1) a method for extracting computational decision models from transaction data and (2) a sensitivity analysis of the effect of market design (i.e., payment structure) and predictability of dispatcher decisions on system performance. The approach is illustrated for the case of a recent debris removal mission following extensive tornadoes in Alabama in 2011 which involved daily dispatching of an average of 28 hauling vehicles to an average of 6 work locations in the region of interest. Results of model validation against these historical tracking data are presented, along with implications for future work.
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ABSTRACT This work explores one aspect of debris removal system design, the optimal mix of hauling vehicles, from two perspectives: efficiency and equity. First, the vehicle mix which maximizes the efficiency of the system is determined... more
ABSTRACT This work explores one aspect of debris removal system design, the optimal mix of hauling vehicles, from two perspectives: efficiency and equity. First, the vehicle mix which maximizes the efficiency of the system is determined (i.e., that which minimizes the average wait time). Secondly, the equity of the most efficient mix is considered (i.e., the ratio of wait times between different vehicles). The results suggest that the solution to the optimal mix of hauling vehicles is nominally the same for a wide range of arrival rates for some system configurations. Further, the analysis shows that the optimal solution permanently disadvantages some vehicles for the majority of service rate combinations, however equitable optimal solutions (i.e., those for which all hauling vehicles have the same expected wait times in the system wait time minimizing solution) do exist, though the locus is very small. System configurations which lead to these equitably optimal solutions are highlighted. Policy implications are also presented.
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ABSTRACT Tradeoffs between multiple dimensions of performance are inherent in the allocation resources in many systems, particularly those with multiple stakeholders. This paper presents numerical results for the case of allocating flows... more
ABSTRACT Tradeoffs between multiple dimensions of performance are inherent in the allocation resources in many systems, particularly those with multiple stakeholders. This paper presents numerical results for the case of allocating flows in central-server closed queueing networks considering several inequity measures over many network configurations. These results show the conflict between server and customer perspectives of equity using multiple measures (server utilization, flow, wait time, and queue length). This paper first compares the effectiveness of the most equitable allocation for each measure relative to the most effective allocation for many network configurations. The complete efficient frontier is then generated using an optimization methodology. The results indicate that for low levels of server rate heterogeneity, all equity measures provide zero inequity allocations with high levels of effectiveness. However, as server rate heterogeneity increases, the total system effectiveness decreases and significant differences between the inequity measures are evident. In particular, the flow equity measure shows marked decreases in effectiveness relative to the other three measures. Further, inequity with respect to wait time, server utilization, and queue length can be eliminated with relatively small impact on total system throughput (i.e., system effectiveness). In contrast, reductions in inequity with respect to customer flow incur large decreases in total system throughput.
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ABSTRACT This paper considers how changes in team composi-tion (such as the number and rate of turnover of team members) are linked to team performance, as assessed in terms of efficiency, ef-fectiveness, and equality (i.e., distribution... more
ABSTRACT This paper considers how changes in team composi-tion (such as the number and rate of turnover of team members) are linked to team performance, as assessed in terms of efficiency, ef-fectiveness, and equality (i.e., distribution of effort). Study data are taken from a large-scale, postdisaster debris removal operation in the USA, collected through existing transaction-level data logging systems. The data enable a detailed (and objective) examination of team performance, thus overcoming many shortcomings of ret-rospective methods such as questionnaires. The results show that the increased turnover diminishes performance along all dimen-sions, while an increased team size contributes to effectiveness but reduces equality. Implications of this study for theory and future empirical work are both discussed.
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Emergencies—whether natural or technological, random or human-induced—may bring profound changes to organizations, the built environment, and society at large. These changes create the need for reliable information about the emergency and... more
Emergencies—whether natural or technological, random or human-induced—may bring profound changes to organizations, the built environment, and society at large. These changes create the need for reliable information about the emergency and its impacts, and thus require responding organizations to seek and process information from an evolving range of sources. By understanding how skilled versus novice response personnel search for information in emergencies, we may begin to understand how to support and train for skillful information seeking in situations characterized by risk, time constraint, and complexity. This study develops a hypothesized model of information-seeking behavior in emergency response and evaluates it using data from expert and novice groups addressing simulated emergency situations. The results suggest that experts maintain breadth in the extent of their information seeking, despite increasing time pressure. Novices, on the other hand, decrease the extent of their search under increasing time pressure. Both expert and novice groups show a decreasing effort in information seeking; moreover, effort devoted to search for common and unique information decreases over time.
Ontologies are a mechanism for storing knowledge in a form that can be shared and possibly integrated into a decision support system. As in the design of other knowledge bases, the design of ontologies requires the elicitation, encoding... more
Ontologies are a mechanism for storing knowledge in a form that can be shared and possibly integrated into a decision support system. As in the design of other knowledge bases, the design of ontologies requires the elicitation, encoding and validation of knowledge gleaned from various sources. One approach to elicitation is the observation and analysis of experts as they perform work in the relevant domain. The analysis of such process data can lead to the identification and encoding of the knowledge that experts apply in practice. Yet despite the relevance of process data to knowledge engineering, the current research provides little guidance on how to capture process data in an ontology. This paper proposes a methodology called Process to Ontology for populating an ontology with expert knowledge as it is reflected in process data. An illustrative example of the methodology's implementation is given using data gathered from a simulated emergency response scenario.
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A methodology is developed for comparing the efficacy of a number of multiple round-robin tournament ranking methods with respect to their ability to replicate the true rank order of players' strengths. Four new ranking methods are... more
A methodology is developed for comparing the efficacy of a number of multiple round-robin tournament ranking methods with respect to their ability to replicate the true rank order of players' strengths. Four new ranking methods are introduced in this paper. Different probability models for pairwise contests between tournament participants are considered. We consider the case in which there are multiple tournaments but not all players compete in all tournaments. Guidelines are provided for selecting a ranking method given some foreknowledge of the form of the distributions of the participants' strengths.
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Abstract In very low-frequency, high-consequence events such as earthquakes or those resulting from malfunctions at commercial nuclear power generating facilities, a group or individual's prior experience with... more
Abstract In very low-frequency, high-consequence events such as earthquakes or those resulting from malfunctions at commercial nuclear power generating facilities, a group or individual's prior experience with crisis events will certainly influence judgments and behavior. Written plans and procedures have been shown to serve valuable purposes in training new organizations, individuals, and public officials for responding to these events. It has been demonstrated repeatedly that when emergency operations are conducted in ...
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Two crucial factors for effective emergency response are the speed with which the response strategy is implemented and the quality of the expert knowledge on which the response is based. We propose a method for using communication and... more
Two crucial factors for effective emergency response are the speed with which the response strategy is implemented and the quality of the expert knowledge on which the response is based. We propose a method for using communication and computing technologies for eliciting and aggregating the knowledge of multiple, geographically separate experts that improves our ability to address these two issues.
Abstract. The 2001 World Trade Center attack resulted in widespread and highly nonroutine failures to critical infrastructure systems. An immediate priority following the attack was the restoration of electric power in lower Manhattan. A... more
Abstract. The 2001 World Trade Center attack resulted in widespread and highly nonroutine failures to critical infrastructure systems. An immediate priority following the attack was the restoration of electric power in lower Manhattan. A study of the organization responsible for conducting this restoration is here presented in order to build theory about organizational characteristics that contribute to resilience.
Abstract Ontologies are a mechanism for storing knowledge in a form that can be shared and possibly integrated into a decision support system. As in the design of other knowledge bases, the design of ontologies requires the elicitation,... more
Abstract Ontologies are a mechanism for storing knowledge in a form that can be shared and possibly integrated into a decision support system. As in the design of other knowledge bases, the design of ontologies requires the elicitation, encoding and validation of knowledge gleaned from various sources. One approach to elicitation is the observation and analysis of experts as they perform work in the relevant domain.
ABSTRACT We investigate the ability of various methods to reveal the true ranking of players competing in multiple incomplete round-robin tournaments, which arise when not all tournament competitions are held. Statistical and graphical... more
ABSTRACT We investigate the ability of various methods to reveal the true ranking of players competing in multiple incomplete round-robin tournaments, which arise when not all tournament competitions are held. Statistical and graphical analyses in this simulation-based study reveal that a method based on players' average winning percentages is usually best. Keywords: multicriteria decision making, pair-wise comparisons, simulation
A methodology is developed for comparing the efficacy of a number of multiple round-robin tournament ranking methods with respect to their ability to replicate the true rank order of players' strengths. Four new ranking methods are... more
A methodology is developed for comparing the efficacy of a number of multiple round-robin tournament ranking methods with respect to their ability to replicate the true rank order of players' strengths. Four new ranking methods are introduced in this paper. Different probability models for pairwise contests between tournament participants are considered. We consider the case in which there are multiple tournaments but not all players compete in all tournaments.
Abstract Technological systems involving hazards are typically managed by experienced personnel guided by well-formulated, pre-determined procedures. These procedures are designed to ensure that operations proceed in a safe and... more
Abstract Technological systems involving hazards are typically managed by experienced personnel guided by well-formulated, pre-determined procedures. These procedures are designed to ensure that operations proceed in a safe and cost-effective manner. Yet normal operations in these systems are exposed to unexpected contingencies that can require personnel to develop and deploy new procedures in real-time.
Abstract In very low-frequency, high-consequence events such as earthquakes or those resulting from malfunctions at commercial nuclear power generating facilities, a group or individual's prior experience with crisis events will certainly... more
Abstract In very low-frequency, high-consequence events such as earthquakes or those resulting from malfunctions at commercial nuclear power generating facilities, a group or individual's prior experience with crisis events will certainly influence judgments and behavior. Written plans and procedures have been shown to serve valuable purposes in training new organizations, individuals, and public officials for responding to these events.
Abstract Much has been already been said about what simulations and games can provide that other research methodologies do not. But the complexity and richness of the results they afford in human factors research is matched by the... more
Abstract Much has been already been said about what simulations and games can provide that other research methodologies do not. But the complexity and richness of the results they afford in human factors research is matched by the complexity and cost of their conception, design, implementation, and validation.
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... 6. Chase, WG and Simon, HA (1973) Perception in chess, Cognitive Psychology, 1, 33-81. ... Levin, IP, Huneke, ME and Jasper, JD (2000) Information processing at successive stages of decision making: need for cognition and... more
... 6. Chase, WG and Simon, HA (1973) Perception in chess, Cognitive Psychology, 1, 33-81. ... Levin, IP, Huneke, ME and Jasper, JD (2000) Information processing at successive stages of decision making: need for cognition and inclusion-exclusion effects, Organizational Behavior ...
Performance support systems provide knowledge and tools for solving problems within complex systems. This paper investigates the use of performance support systems as learning tools: that is, as sources of knowledge to enhance... more
Performance support systems provide knowledge and tools for solving problems within complex systems. This paper investigates the use of performance support systems as learning tools: that is, as sources of knowledge to enhance understanding of problems embedded within complex systems. The study contrasts two different approaches to performance support in conducting engine diagnostics in a military setting. The results of an experiment employing pairs of learners show that one of these approaches–the LockTel ...
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Abstract The recovery and cleanup operation following the September 11, 2001 terrorist attacks on the World Trade Center was a project unlike any other in history. Rising to the challenge, and working around the clock for nine months,... more
Abstract The recovery and cleanup operation following the September 11, 2001 terrorist attacks on the World Trade Center was a project unlike any other in history. Rising to the challenge, and working around the clock for nine months, engineers and construction managers directed the removal of 1.6 million tons of material. Remarkably, this was accomplished ahead of schedule, below budget, and without any serious injury. The success of this operation makes it an excellent candidate for further study. This study ...
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Abstract This chapter presents a thorough review of current practice in eliciting, representing and amalgamating knowledge from multiple experts, with a focus on the use of graphical representations to support the process. The important... more
Abstract This chapter presents a thorough review of current practice in eliciting, representing and amalgamating knowledge from multiple experts, with a focus on the use of graphical representations to support the process. The important points of the discussion are illustrated by presenting a specific methodology for eliciting and combining knowledge from multiple experts. This methodology provides a statistically defensive summarization for assessment. The results of a pilot test of its implementation over the Internet are also presented. The ...
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Abstract Extreme events such as natural or technological disasters challenge society's capabilities both for planning and response. While information technologies and advanced modeling techniques continue to expand how... more
Abstract Extreme events such as natural or technological disasters challenge society's capabilities both for planning and response. While information technologies and advanced modeling techniques continue to expand how society can limit and manage extreme events (Rinaldi, Peerenboom, and Kelly 2001), flexibility remains crucial to the success of planning and response operations (Mileti 1999; Stewart and Bostrom 2002). Non-routine situations (ie, those which require responding organizations to develop and deploy new procedures ...