Uncontrollable Events Research Articles

The effect of controllability and causality on counterfactual thinking

Previous research on counterfactual thoughts about prevention suggests that people tend to focus on enabling rather than causing events and controllable rather than uncontrollable events. Two experiments explore whether counterfactual thinking about enablers is distinct from counterfactual thinking about controllable events. We presented participants with scenarios in which a cause and an enabler contributed to a negative outcome. We systematically manipulated the controllability of the cause and the enabler and asked participants to generate counterfactuals. The results indicate that when only the cause or the enabler is controllable participants undid the controllable event more often. However, when the cause and enabler are matched in controllability participants undid the enabler slightly more often. The findings are discussed in the context of the mental model, functional and judgement dissociation theories as well as previous research on counterfactual thinking. The importance of controllability and possible reasons for the special role of enablers are considered.

Managers' Discretionary Adjustments: The Influence of Uncontrollable Events and Compensation Interdependence

AbstractDiscretionary bonus adjustments allow managers to restore the alignment of employee effort and compensation when bonus amounts are based on noisy objective performance measures. The implications of discretionary adjustments for employees' future efforts and fairness perceptions present important trade‐offs for managers to consider. Adjustments may be used to motivate different types of effort in future periods, but may also create perceptions of unfairness among employees who are not affected by negative events. This study examines the joint influence of the likelihood of future negative uncontrollable events and compensation interdependence (i.e., the extent to which one employee's compensation influences others' compensation) on managers' willingness to make adjustments for the effect of a negative uncontrollable event on a single employee. In our experiment, we manipulate the likelihood of future uncontrollable events and whether bonuses are determined individually or are drawn from a shared bonus pool. Results show that managers are less willing to adjust when the likelihood of future events is high to avoid setting a precedent, thereby motivating employees to adapt to changing conditions. We also find that managers are less willing to adjust, regardless of event likelihood, when compensation interdependence is high, to avoid demotivating unaffected employees. Finally, we find that participants' general attitudes toward compensation significantly influence their adjustment decisions beyond the effects of our independent variables. Our results highlight the unique nature of discretionary adjustments, help explain findings from previous research, and demonstrate important considerations managers must make when using the flexibility provided to them in pay‐for‐performance contracts.

Runway incursion prevention method based on a discrete object sensing event‐driven model

A runway incursion prevention system for high density airports based on an event-driven sensor network is presented, in which non-cooperative active detection sensors, such as microwave or infrared sensors installed beside the critical points of runways and taxiways other than SMR, ADS-B, or MLAT to detect and locate aircraft or vehicle continuously, and the discrete airdrome surface traffic situation can be reconstructed based on the fusion of object sensing events detected by a sensor network and the landing and taking off events reported by pilots. Thus, an airdrome surface operation model based on Petri Nets is proposed based on runway operation rules in the present study. After defining the runway prevention control regulations, runway incursion detection and prevention was transformed into a state forbidden problem. A logical controller that satisfied a strong regulatory condition design method was developed for uncontrollable events in the airdrome surface operation model. The logical controller we proposed is centralised and maximally permissive, and the runway incursion prevention control actions, such as airfield lighting system, can be adopted to execute the discrete control policies generated by logical controller automatically. The illustrated case demonstrated that a controller designed with stop-bar lights or center-line guidance lights could prevent runway incursions in an efficient manner, while its time complexity depended only on the sensor network configurations rather than the number of objects, which is more suitable for high density airports. In general, the combination of active event-driven sensor and discrete event controller is a RIPS solution.

The Interactive Effects ofEx PostGoal Adjustment and Goal Difficulty on Performance

ABSTRACTDespite the common use of performance goals to motivate employees and the use of ex post goal adjustments to filter out the effects of unforeseen and uncontrollable events, minimal research has examined the consequences of employing them jointly. We predict that the availability of ex post goal adjustments will have a positive effect on performance and that this effect will be stronger when the ex ante goal difficulty level is moderate rather than difficult. Moreover, we predict that these effects will be mediated by perceptions of procedural justice. Results from an experiment completed by 142 undergraduate students support our predictions. The availability of ex post goal adjustments has positive effects on procedural fairness perceptions and performance under the moderate goal, but has no such effects under the difficult goal. Implications for future research and practice are discussed.

Vertically Correlated Echelon Model for the Interpolation of Missing Wind Speed Data

The wind speeds of a wind farm are not always available or accurately measurable due to uncontrollable events such as anemometer failures or data transmission errors. However, the data are of great importance for wind resource assessment and wind speed prediction. In this paper, a vertically correlated echelon model (CEM) is proposed to interpolate the missing data of wind speeds by utilizing the correlation of wind speeds at different heights. First, the data of wind speed are checked according to a national standard. Second, the model based on the correlation of wind speeds at different heights is proposed for short interval of missing data. Third, the proposed method is compared with typical interpolation methods and its advantages and disadvantages are discussed. Finally, the uncertainty of the proposed method is analyzed for improved evaluation of interpolation errors.

Hybrid Simulation Environment for Construction Projects: Identification of System Design Criteria

Large construction projects are complex, dynamic, and unpredictable. They are subject to external and uncontrollable events that affect their schedule and financial outcomes. Project managers take decisions along the lifecycle of the projects to align with projects objectives. These decisions are data dependent where data change over time. Simulation-based modeling and experimentation of such dynamic environment are a challenge. Modeling of large projects or multiprojects is difficult and impractical for standalone computers. This paper presents the criteria required in a simulation environment suitable for modeling large and complex systems such as construction projects to support their lifecycle management. Also presented is a platform that encompasses the identified criteria. The objective of the platform is to facilitate and simplify the simulation and modeling process and enable the inclusion of complexity in simulation models.

Managing soil natural capital: An effective strategy for mitigating future agricultural risks?

Uncontrollable events such as adverse weather and volatile prices present considerable risks for arable farmers. Soil natural capital, which views the capacity of soil biodiversity to generate ecosystem services as a component of farm capital, could be important for the stability and resilience of arable production systems. We investigate therefore whether managing soil natural capital could be an effective strategy for mitigating future agricultural risks. We do this by constructing a dynamic stochastic portfolio model to optimize the stock of soil organic carbon (SOC)—our indicator of soil natural capital—when considering both the risks and returns from farming. SOC is controlled via the spatial and temporal allocation of cash crops and an illustrative replenishing land use. We find that higher soil natural capital buffers yield variance against adverse weather and reduces reliance on external inputs. Managing soil natural capital has therefore the potential to mitigate two serious agricultural risks: energy price shocks and adverse weather events, both of which are likely to be exacerbated in the future due to, e.g., globalization and climate change.

The Effects of Ex-Post Goal Adjustment and Social Identity with the Superior on Subordinate Performance

Firms often evaluate subordinate performance relative to a difficult but attainable goal set at the beginning of the evaluation period. For many, a mechanism exists by which these goals may be adjusted downward at the end of the period to account for an uncontrollable negative event. We examine, experimentally, how the knowledge that a downward ex post discretionary goal adjustment is possible affects subordinates’ expectancy of reward and performance in periods where a negative uncontrollable event occurs, and whether high identity, defined as high perceived social connectedness between the superior and subordinate, moderates this effect. We find that high superior-subordinate identity can offset the otherwise negative impact of the potential for downward ex post discretionary goal adjustment on subordinates’ expectancy of reward and performance. Thus, creating an organizational culture that promotes identity between superiors and subordinates can complement incentive-based controls in motivating subordinate performance.

Output feedback controller design of discrete-time linear switching systems

This paper presents some stability synthesis results for the discrete-time linear switching systems whose dynamics contain reset functions and are determined by exogenous and uncontrollable events. First, for autonomous linear switching systems, conditions of stability are given in terms of a new definition of [Formula: see text]-controlled invariant set, and existence conditions to obtain such a set are presented. Then, under the assumption that the discrete state is known and the continuous state is unavailable for feedback, this new result is used to find the sufficient conditions for the existence of an observer-based stabilizing controller and dynamic output feedback controller. Such a design can be formulated in terms of linear matrix inequalities, which are numerically feasible with commercially available software. Finally, illustrative examples are given to indicate the effectiveness of the proposed design.

Phase II study of first-line combined chemotherapy bevacizumab with modified RPMI regimen for elderly or frail patients with unresectable or metastatic colorectal cancer (OGSG0802) update analysis.

e14601 Background: The first-line combined chemotherapy RPMI regimen with bevacizumab (Bmab) in AVF2192g tri al were active. According to the results of efficacy and safety, a fluoropyrimidine (FU) + Bmab regimen is regarded as one of treatment options for 1st-line chemotherapy in many guidelines. We planned a phase II study of modified RPMI regimen with Bmab especially for elderly or frail Pts. Methods: Pts with confirmed unresectable/metastatic colorectal cancer without previous chemotherapy, and not suitable for intensive chemotherapy were enrolled. Pts received modified RPMI regimen (5-FU 600 mg/m2 and l-leucovorin 200 mg/m2 bolus day 1, 8, 15) and Bmab 5 mg/kg day 1, 15, q4w) until disease progression or study withdrawal. The primary endpoint was overall response rate (ORR), and the secondary endpoints were PFS, OS and safety. Results: 41 Pts were enrolled from 13 institutions. Pts characteristics were as follows; median age 76 (range 56-90); male/female, 18/23; ECOG performance status 0/1/2, 21/19/1. The ORR, the rate of best response, the disease control rate (CR+PR+SD) were 36.6%, 56.1%, 85.4%, respectively. Median follow-up period was 14.4 months(Updated results will be presented). 28 Pts (68%) had objective progression and a patient (2.4%) died without progression. The median PFS and OS were 9.0 months (95%CI, 7.5–19.6) and 24.0 months (95%CI, 20.1–NR). The incidences of grade 3 or 4 adverse events were: leukopenia (7%), neutropenia (24%), thrombocytopenia (2%), diarrhea (5%), anorexia (10%), fatigue (5%), stomatitis (7%) and hypertension (5%). Grade 3 febrile neutropenia and grade 4 pulmonary embolism was observed in one pt. Five pts (12%) discontinued the treatment due to severe or uncontrollable adverse event. Conclusions: The modified RPMI regimen with Bmab showed promising activity, and was well tolerated for elderly or frail Pts. ORR and the median PFS of this regimen were similar to historical data with FU + Bmab. This regimen may be a good option for patients with poor PS or elderly with advantages of not requiring percutaneous port placement nor compliance or oral agents. Clinical trial information: UMIN000002182.

Phase II study of first-line combined chemotherapy bevacizumab with modified RPMI regimen for elderly or frail patients with unresectable or metastatic colorectal cancer (OGSG0802).

573 Background: The first-line combined chemotherapy RPMI regimen with bevacizumab (Bmab) in AVF2192g trial for elderly or frail patients (Pts) could be active to progression free survival (PFS), the secondary endpoint, although it may not prolong overall survival (OS), the primary endpoint. According to the results of efficacy and safety studies, a fluoropyrimidine (FU) + Bmab regimen is regarded as an option for 1st-line chemotherapy. We planned a phase II study of modified RPMI regimen with Bmab for elderly or frail Pts. Methods: Pts with confirmed unresectable/metastatic colorectal cancer without previous chemotherapy, and not suitable for intensive chemotherapy were enrolled. Pts received modified RPMI regimen (5-FU 600 mg/m2 and l-leucovorin 200 mg/m2 bolus day 1, 8, 15) and Bmab 5 mg/kg day 1, 15, q4w) until disease progression or study withdrawal. The primary endpoint was overall response rate (ORR), and the secondary endpoints were PFS, OS and safety. Results: 41 Pts were enrolled from 13 institutions. Pts characteristics were; median age 76 (range 56-90); male/female, 18/23; ECOG performance status 0/1/2, 21/19/1. The ORR, the rate of best response, the disease control rate (CR+PR+SD) were 36.6%, 56.1%, 85.4%, respectively. Median follow-up period was 14.4 months. 28 Pts (68%) had objective progression and a patient (2.4%) died without progression. The median PFS and OS were 9.0 months (95%CI, 7.5–19.6) and 24.0 months (95%CI, 20.1–NR). The incidences of grade 3 or 4 adverse events were: leukopenia (7%), neutropenia (24%), thrombocytopenia (2%), diarrhea (5%), anorexia (10%), fatigue (5%), stomatitis (7%) and hypertension (5%). Grade 3 febrile neutropenia and grade 4 pulmonary embolism was observed in one pt. Five pts (12%) discontinued the treatment due to severe or uncontrollable adverse event. Conclusions: The modified RPMI regimen with Bmab showed activity, and was well tolerated for elderly or frail Pts. ORR and the median PFS of this regimen were similar to historical data with FU + Bmab. This regimen may be a good option for not requiring percutaneous port placement Pts. Clinical trial information: UMIN000002182.

Challenges to Field-based Outdoor Research: Pitfalls and Possibilities

Research and evaluation in field-based outdoor settings are often needed to assess program outcomes and ascertain ways to improve programs as well as add to a broader body of knowledge. Although outdoor programs foster an array of important outcomes, research in these settings presents challenges. The purpose of this conceptual paper is to explore the pitfalls and possibilities of field-based outdoor research. Examples of some of the issues encountered in field-based outdoor research include: theory-testing in an applied setting, research that spans multiple sites, garnering support from program staff, Institutional Review Board approval and other ethics issues, designing effective staff training, the appropriateness of instruments in field-data collection, uncontrollable events on site, and the role of parents in longitudinal studies. In each of these areas an explanation of the possibilities and problems are articulated related to these issues.

Following in the Footsteps of Sisyphus:

Following in the Footsteps of Sisyphus:

Robust and nonblocking supervisory control of nondeterministic discrete event systems with communication delay and partial observation

For an uncertain nondeterministic discrete event system (DES) modelled as a set of possible nondeterministic finite state automata, uncontrollable events may subsequently occur before a control action issued by a robust supervisor is applied to the system due to delays in sensing, communicating and actuating. For an uncertain nondeterministic DES under such communication delays and partial observation, this article presents necessary and sufficient conditions for the existence of a robust and nonblocking supervisor to achieve a given language specification for any nondeterministic model in the set. Moreover, this article addresses a synthesis problem of a robust and nonblocking supervisor.

‘Skating on thin ice?’ Consultant surgeon's contemporary experience of adverse surgical events

Concerns about patient safety have prompted studies of adverse surgical events (ASEs), but descriptive classification of errors and malpractice claims have overshadowed qualitative investigations into the processes that lead to expert errors and their solutions. We studied consultant surgeon's perspectives on how and why events occurred through semi-structured interviews about general and specific events. The sample contained heterogeneous cross-section of ages, gender and specialists, with >2 years consultant status and working within a 25-mile radius. Overarching findings included (1) pressures to work harder, faster and beyond capability within a blaming culture; (2) optimism bias from over-confidence and complacency; and (3) multiple pressures to ‘finish’ an operation or list, resulting in completion bias. Seven high order themes were identified on the healthcare system, adverse event types, contributing factors, emotions, cognitive processes, error detection, and strategies, solutions and barriers. The process of classifying event types guided solution selection, and the decision about whether to formally report it. How serious consequences were for patients and their temporal effects, defined an adversity continuum. Minor events arose routinely i.e. technical discrepancies, side-effects. More problematic were sub-optimal outcomes and avoidable events. Despite their expertise, consultants were vulnerable to unavoidable, uncontrollable events which were major concerns. Most serious were near-misses, errors and mistakes. However, major errors did not inevitably lead to a catastrophe and minor errors could be extremely serious. A ‘cascade’ of minor events exacerbated by negative emotions can precipitate major events, and interception methods need investigation. Consultants felt powerless and helpless to change environmental, organisational and systemic problems; new communication and action channels are desirable. Confidence building in team leadership would promote ‘flatter’ hierarchies, facilitating appropriate warnings. Although implementing the WHO Checklist averts important problems, social, environmental and organisational contributing factors are largely overlooked here and in existing models.

Fault-Tolerant Control of Discrete Event Systems based on Fault-Accommodating Models

Fault-tolerant control systems with discrete-event dynamics allow for differing sets of design requirements, that specify the system's behaviour during nominal operation and in the case of component degradation or component malfunction. This paper is concerned with the design of fault-tolerant control algorithms for discrete event systems in the framework of supervisory control theory. Its main contribution is a modelling framework that describes the evolution of systems which are potentially subject to faults. These models are called fault-accommodating models. Within this context, the occurrence of faults is modelled by means of unobservable and uncontrollable events. Hence, the design problem of fault-tolerant controllers is transformed to a supervisory control problem under partial observation. Consequently, there is no need for explicitly diagnosing the occurrence of faults and relaxed diagnosability conditions are applied. Finally, the paper provides extensive examples in order to illustrate the application of all derived methodological results. All computations needed for controller design and system analysis were implemented using a freely available software toolbox.

When does stress help or harm? The effects of stress controllability and subjective stress response on stroop performance.

The ability to engage in goal-directed behavior despite exposure to stress is critical to resilience. Questions of how stress can impair or improve behavioral functioning are important in diverse settings, from athletic competitions to academic testing. Previous research suggests that controllability is a key factor in the impact of stress on behavior: learning how to control stressors buffers people from the negative effects of stress on subsequent cognitively demanding tasks. In addition, research suggests that the impact of stress on cognitive functioning depends on an individual’s response to stressors: moderate responses to stress can lead to improved performance while extreme (high or low) responses can lead to impaired performance. The present studies tested the hypothesis that (1) learning to behaviorally control stressors leads to improved performance on a test of general executive functioning, the color-word Stroop, and that (2) this improvement emerges specifically for people who report moderate (subjective) responses to stress. Experiment 1: Stroop performance, measured before and after a stress manipulation, was compared across groups of undergraduate participants (n = 109). People who learned to control a noise stressor and received accurate performance feedback demonstrated reduced Stroop interference compared with people exposed to uncontrollable noise stress and feedback indicating an exaggerated rate of failure. In the group who learned behavioral control, those who reported moderate levels of stress showed the greatest reduction in Stroop interference. In contrast, in the group exposed to uncontrollable events, self-reported stress failed to predict performance. Experiment 2: In a second sample (n = 90), we specifically investigated the role of controllability by keeping the rate of failure feedback constant across groups. In the group who learned behavioral control, those who reported moderate levels of stress showed the greatest Stroop improvement. Once again, this pattern was not demonstrated in the group exposed to uncontrollable events. These results suggest that stress controllability and subjective response interact to affect high-level cognitive abilities. Specifically, exposure to moderate, controllable stress benefits performance, but exposure to uncontrollable stress or having a more extreme response to stress tends to harm performance. These findings may provide insights on how to leverage the beneficial effects of stress in a range of settings.

Positive and negative affect in illusion of control

Research regarding the illusion of control was dominated by the studies examining the effect of depressive affect on the overestimation of control over uncontrollable events. However, the relative contributions of high Negative Affect (NA) and low Positive Affect (PA), as underlying dimensions of depressive states, has remained unclear. This study researched how both PA and NA had affected the illusion of control. Two weeks before illusion induction, trait PA and NA of 54 first-year university students were assessed, and just before and after illusion induction task their state forms were estimated. The induction consisted of solving unsolvable tasks and obtaining positive feedback for all the answers. The illusion of control was significantly correlated with all three PA scores, and none of the NA. After controlling for trait measures, the PA after illusion induction remained the only significant predictor of illusion. The relation of positive affect and illusory judgement in maintaining mental health were discussed.

Behavior Coordination of Mobile Robotics Using Supervisory Control of Fuzzy Discrete Event Systems

In order to incorporate the uncertainty and impreciseness present in real-world event-driven asynchronous systems, fuzzy discrete event systems (DESs) (FDESs) have been proposed as an extension to crisp DESs. In this paper, first, we propose an extension to the supervisory control theory of FDES by redefining fuzzy controllable and uncontrollable events. The proposed supervisor is capable of enabling feasible uncontrollable and controllable events with different possibilities. Then, the extended supervisory control framework of FDES is employed to model and control several navigational tasks of a mobile robot using the behavior-based approach. The robot has limited sensory capabilities, and the navigations have been performed in several unmodeled environments. The reactive and deliberative behaviors of the mobile robotic system are weighted through fuzzy uncontrollable and controllable events, respectively. By employing the proposed supervisory controller, a command-fusion-type behavior coordination is achieved. The observability of fuzzy events is incorporated to represent the sensory imprecision. As a systematic analysis of the system, a fuzzy-state-based controllability measure is introduced. The approach is implemented in both simulation and real time. A performance evaluation is performed to quantitatively estimate the validity of the proposed approach over its counterparts.

Modular Synthesis of Maximally Permissive Opacity-Enforcing Supervisors for Discrete Event Systems

In this paper, we study opacity-enforcing supervisory control of discrete event systems. We consider the case that the secrete behavior of the system is specified by multiple secret languages, and synthesize a maximally permissive supervisor that enforces opacity for all secret languages. We prove that, under a certain assumption on observable and uncontrollable events, a maximally permissive opacity-enforcing supervisor can be synthesized in a modular fashion.