Safety as an Emergent Property: Investigation into the Work Practices of High-Reliability Framing Crews

With regards to safety, the challenge for researchers and practitioners is to develop work systems that can achieve at the same time high levels of productivity and safety. Towards this objective, this research investigates the work practices of high-reliability crews—that is, crews who perform high-risk work with exceptionally high productivity and safety. The objective of the research is to increase understanding of the work practices that reduce the likelihood of accidents while at the same time increase productivity. This paper presents the findings of an initial exploratory study that compares the work practices of two residential framing crews: one crew with consistently exceptional levels of safety and productivity, and one average-performing crew from the same company. The two crews did not show any difference in safety practices—both crews had high compliance with the company’s safety requirements. However, the production practices of the high-reliability crew were shaped by a clear “guiding principle,” which is a strong focus on avoiding errors and rework, and by specific strategies that support this principle. Such strategies include actions to prevent disruptions, controlling the production pressures, matching skills with task demands, and carefully preparing and coordinating the high demand tasks. These practices prevent production errors while also reducing the likelihood of accidents. The findings provide directions for further research.     

Dissociating working memory from task difficulty in human prefrontal cortex

A functional magnetic resonance imaging (fMRI) study was conducted to determine whether prefrontal cortex (PFC) increases activity in working memory (WM) tasks as a specific result of the demands placed on WM, or to other processes affected by the greater difficulty of such tasks. Increased activity in dorsolateral PFC (DLPFC) was observed during task conditions that placed demands on active maintenance (long retention interval) relative to control conditions matched for difficulty. Furthermore, the activity was sustained over the entire retention interval and did not increase when task difficulty was manipulated independently of WM requirements. This contrasted with the transient increases in activity observed in the anterior cingulate, and other regions of frontal cortex, in response to increased task difficulty but not WM demands. Thus, this study established a double-dissociation between regions responsive to WM versus task difficulty, indicating a specific involvement of DLPFC and related structures in WM function.     

New Method for Measuring the Safety Risk of Construction Activities: Task Demand Assessment

The task demand assessment (TDA) is a new technique for measuring the safety risk of construction activities and analyzing how changes in operation parameters can affect the potential for accidents. TDA is similar to observational ergonomic methods—it does not produce estimates of probabilities of incidents, but it quantifies the “task demand” of actual operations based on characteristics of the activity and independent of the workers’ capabilities. The task demand reflects the difficulty to perform the activity safely. It is based on (1) the exposure to a hazard and (2) the presence and level of observable task demand factors—that is, risk factors that can increase the potential for an accident. The paper presents the findings from the initial implementation of TDA and demonstrates its feasibility and applicability on two different operations: a roofing activity and a concrete paving operation. Furthermore, the paving case illustrates how the TDA method can compare different production scenarios and measure the effect of production variables on the accident potential. The findings indicate that the method can be applied on activities of varying complexity and can account for several risks and task demand factors as required by the user. The selection of task demand factors is a key issue for the validity of the method and requires input from the crew and safety management. The limitations of the methodology and the need for further research are discussed. Overall, TDA provides a tool that can assist researchers and practitioners in the analysis and design of construction operations.     

Something’s got to give: The effects of dual-goal difficulty, goal progress, and expectancies on resource allocation.

The current study developed and tested a model of the interplay among goal difficulty, goal progress, and expectancy over time in influencing resource allocation toward competing demands. The results provided broad support for the theoretical model. As predicted, dual-goal expectancy—the perceived likelihood of meeting both goals in competition—played a central role, moderating the relationship between relative goal progress and resource allocation. Dual-goal difficulty was also found to exert an important influence on multiple-goal self-regulation. Although it did not influence total productivity across both tasks combined, it did combine with other model components to influence the relative emphasis of one task over another. These results suggest that the cumulative demands placed by multiple difficult goals may exceed individuals’ perceived capabilities and may lead to partial or total abandonment of 1 goal to ensure attainment of the other. The model helps shed light on some of the conflicting theoretical propositions and empirical results obtained in prior work. Implications for theory and research regarding multiple-goal self-regulation are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Processing of stimulus properties: Evidence for dual-task integrality.

Assessed the conditions under which dual-task integrality can be fostered by manipulating 4 factors likely to influence the integrality between tasks: intertask redundancy (ITD), the spatial proximity of primary and secondary task displays, the degree to which primary and secondary task displays constitute a single object, and the resource demands of the 2 tasks. The resource allocation policy was inferred from changes in the amplitude of the P300 component of the event-related brain potential. 12 university students participated in 3 experimental sessions in which they performed both single and dual tasks. The primary task was a pursuit step tracking task. The secondary tasks required Ss to discriminate between different intensities or different spatial positions of a stimulus. Task pairs that required the processing of different properties of the same object resulted in better performance than task pairs that required the processing of different objects. These same object-task pairs led to a positive relation between primary task difficulty and the resources allocated to secondary task stimuli. ITD and the physical proximity of task displays produced similar effects of reduced magnitude. (54 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

How leaders self-regulate their task performance: Evidence that power promotes diligence, depletion, and disdain.

When leaders perform solitary tasks, do they self-regulate to maximize their effort, or do they reduce effort and conserve their resources? Our model suggests that power motivates self-regulation toward effective performance—unless the task is perceived as unworthy of leaders. Our 1st studies showed that power improves self-regulation and performance, even when resources for self-regulation are low (ego depletion). Additional studies showed that leaders sometimes disdain tasks they deem unworthy, by withholding effort (and therefore performing poorly). Ironically, during ego depletion, leaders skip the appraisal and, therefore, work hard regardless of task suitability, so that depleted leaders sometimes outperform nondepleted ones. Our final studies replicated these patterns with different tasks and even with simple manipulation of framing and perception of the same task (Experiment 5). Experiment 4 also showed that the continued high exertion of leaders when depleted takes a heavy toll, resulting in larger impairments later. The judicious expenditure of self-control resources among powerful people may help them prioritize their efforts to pursue their goals effectively. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fuzzy Preference Relations Consensus Approach to Reduce Conflicts on Shared Responsibilities in the Owner Managing Contractor Delivery System

This paper proposes a fuzzy preference relations consensus (FPRC) approach that helps owners and contractors reach consensus on their responsibilities and reduce conflicts in shared tasks. A fuzzy similarity consensus (FSC) model was developed to aggregate experts’ opinions on roles and responsibilities in the owner managing contractor (OMC) project delivery system. The FSC model categorized 324 generic OMC tasks into three responsibility task lists: owner, contractor, and shared. In a consensus-reaching process, the FPRC approach is applied to shared tasks, where expert opinions on responsibility conflict are expressed, to achieve an aggregated responsibility decision for each task. Experts compare the three responsibility alternatives in pairs by using linguistic preferences, defined on a fuzzy preference scale, to select a preferred responsibility alternative for each of the conflicting tasks. A computed linguistic consensus degree guides the experts on their level of consensus in every round of the process. The quality of experts is defined with a fuzzy expert system–determined importance weight factor for each expert. The FPRC approach is relevant to the construction industry, as it incorporates consistency in decision making by allowing experts to measure and reach an adequate level of consensus linguistically when deciding on responsibilities. The proposed approach provides a method of reducing conflicts in the assignment of task responsibility between the owner and its contractors as early as the project initiation phase; thus, the project teams can concentrate on the work to be done rather than deal with responsibility conflicts during project execution.     

Goal orientation and task demand effects on motivation, affect, and performance.

Two studies tested the joint effects of goal orientation and task demands on motivation, affect, and performance, examining different factors affecting task demands. In Study 1 (N?=?199), task difficulty was found to moderate the effect of goal orientation on performance and affect (i.e., satisfaction with performance). In Study 2 (N?≠&189), task consistency was found to moderate the effect of goal orientation on self-efficacy and intrinsic motivation. Results are discussed in relation to self-regulatory processes cued by goal orientations, attentional resource demands, and the need to match goal orientations to the nature of the task. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Encoding, retrieval, main effects and interactions: Were Lockhart and Craik (1990) on the level?

Investigated whether a main effect of encoding emerges when retrieval tests are equated for difficulty. 132 introductory psychology students were tested in 2 experiments. Ss encoded words semantically or by rhyme, and then judged whether unstudied words were related to studied words. A list structure (L. Jacoby, 1975) was adapted to remove the overall difference in difficulty across semantic and rhyme retrieval tasks. Results indicate no main effect of retrieval task, and the main effect of encoding was not dependent on the retrieval task. Semantic encoding led to a greater likelihood that Ss would judge an unstudied word to be related to a studied word. It was concluded that test words shared either a semantic or a rhyme relation with studied words, the advantage of semantic encoding was not dependent on the retrieval criterion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Elaboration d'un instrument de mesure des habiletés socio-cognitives chez l'enfant de cinq à dix ans.

To assess social cognitive skills in children, a special test was constructed with cognitive and linguistic demands adapted to young children. The test consisted of 4 tasks that were submitted to 200 children, aged 5–10 yrs. Three tasks were devised to measure cognitive role-taking and the 4th to measure referential communication. Results show a significant increase in performance with age for each task and a significant increasing order of difficulty in the tasks. Thus, each task corresponded to specific levels in the development of role-taking skills. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Developmental stability in jumping.

The principles of dynamical systems were used to study the effects of changing internal (i.e., developing subsystems) and external (i.e., task demands) constraints on the development of jumping. Children, 3, 5, 7, and 9 years old, and 3 groups of adults—of average skill, skilled in volleyball, and skilled in gymnastics—were filmed performing two different tasks, a standing long jump and a vertical jump. The results revealed that despite changes in both external and internal constraints, there were no differences in the pattern of coordination for jumping. Differences were found in the position and magnitude variables. Clearly, the constraints manipulated here were insufficient to disrupt the stability of the jump's coordination. We suggest that these results indicate that jumping is a stable movement organization that transcends the changes in constraints associated with developing subsystems and particular task demands. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Easier Tasks Can Have Better Discriminating Power: The Case of Verbal Fluency.

Loren and Jean Chapman highlighted the importance that the psychometric characteristics of a task may have when comparing different populations (L. J. Chapman & J. P. Chapman, 1973, 1978). Specifically, they pointed out that when comparing 2 tasks measuring different constructs, there is a greater likelihood of finding larger deficits on a task with higher discriminating power, irrespective of what the task measures. While researchers have addressed this issue, they typically have assumed that more difficult tasks have greater discriminating power, often without actually measuring discriminating power. In this article, the authors present data from 2 studies using phonologic and category fluency tasks to demonstrate that the critical factor for task selection and matching is discriminating power, not task difficulty. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Framing of task performance strategies: effects on performance in a multiattribute dynamic decision making environment

It is well documented that the way a static choice task is "framed" can dramatically alter choice behavior, often leading to observable preference reversals. This framing effect appears to result from perceived changes in the nature or location of a person's initial reference point, but it is not clear how framing effects might generalize to performance on dynamic decision making tasks that are characterized by high workload, time constraints, risk, or stress. A study was conducted to examine the hypothesis that framing can introduce affective components to the decision making process and can influence, either favorably (positive frame) or adversely (negative frame), the implementation and use of decision making strategies in dynamic high-workload environments. Results indicated that negative frame participants were significantly impaired in developing and employing a simple optimal decision strategy relative to a positive frame group. Discussion focuses on implications of these results for models of dynamic decision making.     

Working-memory-triggered dynamic adjustments in cognitive control.

Dynamic adjustments in cognitive control are well documented in conflict tasks, wherein competition from irrelevant stimulus attributes intensifies selection demands and leads to subsequent performance benefits. The current study investigated whether mnemonic demands, in a working memory (WM) task, can drive similar online control modifications. Demand levels (high vs. low) of WM maintenance (memory load of 2 items vs. 1 item) and delay-spanning distractor interference (confusable vs. not confusable with memoranda) were manipulated using a factorial design during a WM delayed-recognition task. Performance was best subsequent to trials in which both maintenance and distractor interference demands were high, followed by trials with high demand in either of these 2 control domains, and worst following trials with low demand in both domains. These results suggest that dynamic adjustments in cognitive control are not triggered exclusively by conflict-specific contexts but are also triggered by WM demands, revealing a putative mechanism by which this system configures itself for successful task performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age-related deficits in generation and manipulation of mental images: I. The role of sensorimotor speed and working memory.

The authors investigated age-related slowing of information processing in mental imagery tasks. Eighty-five healthy adults (ages 18 to 77) performed a visual, sensorimotor, reaction-time task; a visual-perceptual choice reaction task; and 3 mental imagery tasks that varied in apparent difficulty and involved stimuli at 2 levels of graphic complexity. Age was associated with prolongation of response time across all tasks and both levels of stimulus complexity. Accuracy of response was adversely affected by increase in stimulus complexity in all tasks, whereas it was negatively related to age only on the tasks with substantial mental imagery requirements. Slowing of information processing and reduction in accuracy were mediated by declines in working memory but not by decrease of sensorimotor speed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Understanding the strategies of document literacy and their conditions of use.

The relative difficulty of document reading-to-do strategies and how these strategies combine with different structure and processing conditions as contributors to task difficulty were examined. To accomplish this, the extent to which different types of strategies and their related structure and processing conditions would influence difficulty on 217 tasks drawn from the document scales of five national adult surveys was investigated. The study identified a difficulty hierarchy of strategies. When combined with 4 predictor variables (i.e., document complexity, type of information, type of match, plausibility of distractors), strategy types accounted for 80% of the variance in task difficulty. A new framework for conceptualizing and measuring the document reading-to-do task domain is discussed, and the advantages of this framework for researchers, test designers, curriculum developers, and document designers also are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dyadic performance on two tasks as a function of task difficulty, work strategy, and member ability.

Replicated the manipulation of divided and shared labor used in previous studies by the present author (see PA, Vol 49:1265 and Vol 51:2005), while varying task difficulty and member ability in order to examine their combined effects upon dyadic performance on 2 tasks: analogies and crossword puzzles. Ss were 72 US Army enlisted men; 54 had a mean of 12.4 yrs of education, and 18 were technicians with a mean of 3.6 yrs of higher education. Dividing labor was found to be more efficient in terms of man-hours to a performance criterion, but sharing labor was more effective (i.e., it produced greater total performance). The efficiency effect was more pronounced on the analogies tasks, while the effectiveness findings were more pronounced on the crossword puzzles. Results occurred across task difficulty and group ability. The hypothesis that task difficulty would indicate the importance of ability redundancy on group performance was not supported. Differences in the performance curves for the 2 tasks are discussed in terms of the role of feedback regarding the adequacy of a response to the task. It is suggested that a distinction be made between task difficulty and task complementarity when considering the effects of ability redundancy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On the relation between abilities, learning, and human performance.

Describes the author's research efforts to link basic and applied psychology concepts in each of the following areas: aptitude measurement, learning and training, and human task performance. Several studies are described in detail to illustrate a number of broad issues, particularly the possibility of using combinations of experimental and correlational methods for studying complex human behavior, and the need to develop concepts that allow more dependable generalization of research findings to new situations (particularly to new tasks). A taxonomy of human perceptual-motor abilities is described and related to more complex tasks. Other studies investigated the relationship between abilities and skill acquisition; individual differences in various learning phenomena (e.g., transfer of training); and whether the taxonomic categories are useful for standardizing laboratory tasks and for generalizing results of these tasks to new tasks. Results suggest that (a) experimental-correlational studies can be used to develop a body of principles relating task dimensions to ability requirements; (b) kinesthetic ability factors become more important than spatial ones as psychomotor learning progresses; and (c) it should be possible to develop a data base about human performance, indexed by type of task. (37 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Contractor Selection Criteria: Investigation of Opinions of Singapore Construction Practitioners

The construction industry has witnessed the failure of many contractors due to varying reasons such as financial problems, poor performance, or accidents arising from the lack of adequate safety consideration at worksites. All these incidents have led to the impression that the current system of awarding the contracts is inefficient in selecting the contractor capable of meeting the demands and challenges of present times and hence needs to be reviewed accordingly. Therefore, in an attempt to investigate the current situation of the Singapore construction industry a questionnaire survey was conducted for accruing the data required to identify the important contractor selection criteria (CSC) and to draw upon construction practitioners’ opinions regarding the importance of those CSC in assessing the capabilities of the candidate contractors during the selection process. The research reported upon forms part of a larger study that aims to develop a computer-interactive multicriteria decision system for contractor selection involving identification of CSC for inclusion in the system, investigation of CSC preferences of construction practitioners, and establishment of weights for those CSC from their perceived importance determined through the questionnaire survey of Singapore construction practitioners. The study highlights that there are statistically significant differences in opinions regarding the degree of importance assigned to some CSC among public clients, private clients, and contractors. Findings from the study may act as an aid in improving the Singapore construction industry by helping construction clients identify multiple CSC apart from cost which should always be considered when assessing the capability of candidate contractors during the selection process, by assisting contractors in improving their attributes in line with clients’ preferences and by facilitating Singapore construction clients and researchers to develop a contractor selection system capable of assessing multiple attributes of the candidate contractors so that the risk of the project failure due to the selection of an inappropriate contractor is minimized.     

Self-regulatory functions of children's private speech: A critical analysis of recent challenges to Vygotsky's theory.

Recent empirical findings have challenged L. S. Vygotsky's (1962) theory regarding the self-regulatory functions of children's private speech by suggesting that such speech occurs infrequently and that there is little functional relationship between children's production of private speech and success in cognitive tasks. It is hypothesized that the scarcity of private speech is an artifact of the typical research paradigm used in recent investigations. Within a Vygotskian framework, private speech will tend to co-occur with failure in cognitive tasks because both private speech and the likelihood of failure increase with task difficulty. In the present study, 32 3.5–6 yr olds were videotaped while performing semantic and perceptual tasks, and their verbalizations were transcribed and coded into social and private speech categories. Results indicate that the condition most frequently used in recent studies indeed minimized production of private speech and that failure in tasks was associated with greater production of self-regulatory speech. As the number of self-regulatory utterances declined, the number of whispers and mutterings increased, supporting Vygotsky's notion that private speech does not disappear with age but "goes underground" to constitute inner speech. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)