847 resultados para reward
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Despite the organizational benefits of treating employees fairly, both anecdotal and empirical evidence suggest that managers do not behave fairly towards their employees in a consistent manner. As treating employees fairly takes up personal resources such as time, effort, and attention, I argue that when managers face high workloads (i.e., high amounts of work and time pressure), they are unable to devote such personal resources to effectively meet both core technical task requirements and treat employees fairly. I propose that in general, managers tend to view their core technical task performance as more important than being fair in their dealings with employees; as a result, when faced with high workloads, they tend to prioritize the former at the expense of the latter. I also propose that managerial fairness will suffer more as a result of heightened workloads than will core technical task performance, unless managers perceive their organization to explicitly reward fair treatment of employees. I find support for my hypotheses across three studies: two experimental studies (with online participants and students respectively) and one field study of managers from a variety of organizations. I discuss the implications of studying fairness in the wider context of managers’ complex role in organizations to the fairness and managerial work demands literatures.
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Introduction : Patients with mild cognitive impairme nt (MCI) may make suboptimal decisions particularly in complex situations, and thi s could be due to temporal discounting, the tendency to prefer immediate rewards over delayed but larger rewards. The present study proposes to evaluate intertemporal prefere nces in MCI patients as compared to healthy controls. Method : Fifty-five patients with MCI and 57 h ealthy controls underwent neuropsy- chological evaluation and a delay discounting questionnaire, which evaluates three para- meters: hyperbolic discounting ( k ), the percentage of choices for delayed and later rewards (%LL), and response consistency (Acc). Results : No significant differences were found in the delay discounting questionnaire between MC I patients and controls for the three reward sizes considered, small, medium, and large, using both k and %LL parameters. There were also no differences in the response consistency, Acc, between the two groups. Conclusions : Patients with MCI perform similarly to healthy controls in a delay discounting task. Memory deficits do not notably affect intertemporal preferences.
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Object recognition has long been a core problem in computer vision. To improve object spatial support and speed up object localization for object recognition, generating high-quality category-independent object proposals as the input for object recognition system has drawn attention recently. Given an image, we generate a limited number of high-quality and category-independent object proposals in advance and used as inputs for many computer vision tasks. We present an efficient dictionary-based model for image classification task. We further extend the work to a discriminative dictionary learning method for tensor sparse coding. In the first part, a multi-scale greedy-based object proposal generation approach is presented. Based on the multi-scale nature of objects in images, our approach is built on top of a hierarchical segmentation. We first identify the representative and diverse exemplar clusters within each scale. Object proposals are obtained by selecting a subset from the multi-scale segment pool via maximizing a submodular objective function, which consists of a weighted coverage term, a single-scale diversity term and a multi-scale reward term. The weighted coverage term forces the selected set of object proposals to be representative and compact; the single-scale diversity term encourages choosing segments from different exemplar clusters so that they will cover as many object patterns as possible; the multi-scale reward term encourages the selected proposals to be discriminative and selected from multiple layers generated by the hierarchical image segmentation. The experimental results on the Berkeley Segmentation Dataset and PASCAL VOC2012 segmentation dataset demonstrate the accuracy and efficiency of our object proposal model. Additionally, we validate our object proposals in simultaneous segmentation and detection and outperform the state-of-art performance. To classify the object in the image, we design a discriminative, structural low-rank framework for image classification. We use a supervised learning method to construct a discriminative and reconstructive dictionary. By introducing an ideal regularization term, we perform low-rank matrix recovery for contaminated training data from all categories simultaneously without losing structural information. A discriminative low-rank representation for images with respect to the constructed dictionary is obtained. With semantic structure information and strong identification capability, this representation is good for classification tasks even using a simple linear multi-classifier.
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Being married may raise worker productivity and increase the probability of remaining in a job and, as consequence, obtaining a wage premium -- Yet, this effect may be different for males and females -- In developing countries, such as Colombia, the premium may be larger than in developed countries due to the differing social norms and labor market structures -- Using cross-sectional data from Colombian Household Surveys, this paper examines the marriage wage premium and its evolution in Colombia both at the aggregate level and by gender -- We find a marriage wage premium for both male and female populations; this wage premium is explained by the greater human capital endowment in married people and to employer favoritism due to the “social norms” which consider being married an appropriate behavior and reward it
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Everyday, humans and animals navigate complex acoustic environments, where multiple sound sources overlap. Somehow, they effortlessly perform an acoustic scene analysis and extract relevant signals from background noise. Constant updating of the behavioral relevance of ambient sounds requires the representation and integration of incoming acoustical information with internal representations such as behavioral goals, expectations and memories of previous sound-meaning associations. Rapid plasticity of auditory representations may contribute to our ability to attend and focus on relevant sounds. In order to better understand how auditory representations are transformed in the brain to incorporate behavioral contextual information, we explored task-dependent plasticity in neural responses recorded at four levels of the auditory cortical processing hierarchy of ferrets: the primary auditory cortex (A1), two higher-order auditory areas (dorsal PEG and ventral-anterior PEG) and dorso-lateral frontal cortex. In one study we explored the laminar profile of rapid-task related plasticity in A1 and found that plasticity occurred at all depths, but was greatest in supragranular layers. This result suggests that rapid task-related plasticity in A1 derives primarily from intracortical modulation of neural selectivity. In two other studies we explored task-dependent plasticity in two higher-order areas of the ferret auditory cortex that may correspond to belt (secondary) and parabelt (tertiary) auditory areas. We found that representations of behaviorally-relevant sounds are progressively enhanced during performance of auditory tasks. These selective enhancement effects became progressively larger as you ascend the auditory cortical hierarchy. We also observed neuronal responses to non-auditory, task-related information (reward timing, expectations) in the parabelt area that were very similar to responses previously described in frontal cortex. These results suggests that auditory representations in the brain are transformed from the more veridical spectrotemporal information encoded in earlier auditory stages to a more abstract representation encoding sound behavioral meaning in higher-order auditory areas and dorso-lateral frontal cortex.
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Mental stress is known to disrupt the execution of motor performance and can lead to decrements in the quality of performance, however, individuals have shown significant differences regarding how fast and well they can perform a skilled task according to how well they can manage stress and emotion. The purpose of this study was to advance our understanding of how the brain modulates emotional reactivity under different motivational states to achieve differential performance in a target shooting task that requires precision visuomotor coordination. In order to study the interactions in emotion regulatory brain areas (i.e. the ventral striatum, amygdala, prefrontal cortex) and the autonomic nervous system, reward and punishment interventions were employed and the resulting behavioral and physiological responses contrasted to observe the changes in shooting performance (i.e. shooting accuracy and stability of aim) and neuro-cognitive processes (i.e. cognitive load and reserve) during the shooting task. Thirty-five participants, aged 18 to 38 years, from the Reserve Officers’ Training Corp (ROTC) at the University of Maryland were recruited to take 30 shots at a bullseye target in three different experimental conditions. In the reward condition, $1 was added to their total balance for every 10-point shot. In the punishment condition, $1 was deducted from their total balance if they did not hit the 10-point area. In the neutral condition, no money was added or deducted from their total balance. When in the reward condition, which was reportedly most enjoyable and least stressful of the conditions, heart rate variability was found to be positively related to shooting scores, inversely related to variability in shooting performance and positively related to alpha power (i.e. less activation) in the left temporal region. In the punishment (and most stressful) condition, an increase in sympathetic response (i.e. increased LF/HF ratio) was positively related to jerking movements as well as variability of placement (on the target) in the shots taken. This, coupled with error monitoring activity in the anterior cingulate cortex, suggests evaluation of self-efficacy might be driving arousal regulation, thus affecting shooting performance. Better performers showed variable, increasing high-alpha power in the temporal region during the aiming period towards taking the shot which could indicate an adaptive strategy of engagement. They also showed lower coherence during hit shots than missed shots which was coupled with reduced jerking movements and better precision and accuracy. Frontal asymmetry measures revealed possible influence of the prefrontal lobe in driving this effect in reward and neutral conditions. The possible interactions, reasons behind these findings and implications are discussed.
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Dissertação de Mestrado apresentada ao Instituto Superior de Psicologia Aplicada para obtenção de grau de Mestre na especialidade de Psicologia Social e das Organizações.
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Impulse control disorders (ICD) is a common side effect of the dopaminergic treatment in patients with Parkinson's disease, which is more associated with dopamine agonists than with levodopa. To understand its pathophysiology, reliable animal models are essential. Using the variable delay-to-signal (VDS) paradigm, impulsivity was evaluated in bilateral parkinsonian rats treated with pramipexole (PPX). In this test, rats have to introduce the snout into a nose poke that is signaled by a light (presented at variable delays) triggering the delivery of a food reward after a correct response. Reaching a stable baseline performance, a partial bilateral dopaminergic lesion with 6-OHDA was induced in the dorsolateral striatum (AP: +1mm, L: ±3.4mm, V:-4.7 mm, Bregma). Rats undertook the VDS test under 5 conditions: basal state, 6-OHDA-induced lesion, the effect of two doses of PPX (0,25mg/kg and 3mg/kg; Latin-square design), and the day after the last dose of PPX. Only the acute administration of 3 mg/kg of PPX significantly rised the number of premature responses, indicating an increase of impulsive behavior, in parkinsonian but not in sham rats. Both doses of PPX significantly decreased the accuracy of responding (correct/total number of responses) and increased the incorrect and perseverative (compulsive behavior) responses in both parkinsonian and sham treated groups when compared with saline-treated groups. In conclusion, PPX induced attention deficit (lack of accuracy) as well as compulsive behavior in control and parkinsonian rats, but increased impulsivity only in the parkinsonian animals. This model could constitute a valid tool to investigate the pathophysiology of ICD.
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Aims. Cocaine addiction is a chronically relapsing disorder characterized by the compulsion to seek and take the drug. Previous investigations have demonstrated that several drugs of abuse, as cocaine, can alter the levels of lipid-based signalling molecules such as the N-acylethanolamines (NAEs). In addition, NAEs levels in the brain are sensitive to cocaine self-administration and extinction training. In this context, this study aimed to investigate the effect of repeated and acute palmitoylethanolamide (PEA), an endogenous NAE, on the behavioural effects of cocaine using mouse models of conditioned reward and psychomotor activation. Methods. Using male C57BL/6J mice, the ability of repeated PEA injections (1 or 10 mg/kg i.p) to modulate the development of a conditioned place preference (CPP) and behavioural sensitization (BS) induced by cocaine (20 mg/kg i.p.) was evaluated. In addition, the expression of cocaine-induced CPP and BS after acute PEA administration was also studied. Results. PEA (1 and 10 mg/kg i.p) significantly reduced the development of cocaine-induced BS, but did not modify the acquisition of cocaine-induced CPP. Furthermore, both doses of PEA were able to reduce the expression of BS and CPP. Conclusions. Altogether, these findings show that exogenous administration of PEA attenuated psychomotor activation and impaired the expression of CPP induced by cocaine. Our results may be relevant in order to understand the role of NAEs in the development and treatment of cocaine addiction.
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El presente estudio corresponde a una investigación cuantitativa realizada en la ciudad de Cuenca, Ecuador, cuyo objetivo fue determinar las prácticas parentales en la función de socialización de la familia. Se trabajó con una muestra de 445 padres con hijos en segundo año de educación básica, a quienes se aplicó el cuestionario “Estudio socioeducativo de hábitos y tendencias de comportamiento en familias de niños de segundo año de educación básica” (Torio, 2001). Luego del procesamiento de la información se encontró que: a) El cuidado de los hijos y administración de recursos para el hogar son actividades que los padres realizan de manera conjunta; las actividades escolares y preparación de alimentos recae generalmente en las madres; b) la participación de los padres en los juegos es diferente según el tipo de juego: los padres tienden a involucrarse en juegos que demandan actividad física y las madres en juegos didácticos; c) la verdad, la solidaridad y la responsabilidad son los valores que los padres/madres mencionan transmitir y los que consideran de mayor importancia; d) los besos, abrazos y caricias son estrategias que los padres/madres utilizan para premiar a sus hijos, en tanto que la prohibición de cosas lo utilizan como castigo, en consecuencia los padres/madres cuencanos son más expresivos que instrumentales.
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No Brasil, as macrófitas aquáticas submersas, Egeria densa e Egeria najas, têm causado prejuízos aos usos múltiplos da água. Hydrilla verticillata foi recentemente introduzida, mas tem histórico como planta problemática nos EUA, no México e na Austrália. O objetivo deste trabalho foi avaliar as suscetibilidades relativas dessas três macrófitas aquáticas ao diquat e os riscos da utilização desse herbicida para o guaru (Phallocerus caudimaculatus). Para isso, foram instalados ensaios em condições de laboratório, a fim de avaliar a suscetibilidade relativa das três macrófitas por meio da manutenção de ponteiros dessas plantas em soluções contendo 0,0; 0,2; 0,4; 0,8; e 1,6 mg L-1 de diquat (Reward®) por 14 dias. A avaliação foi realizada pela variação do acúmulo de matéria fresca e do comprimento dos ponteiros no período de exposição ao herbicida. H. verticillata mostrou maior sensibilidade ao diquat em comparação com as duas macrófitas do gênero Egeria, mesmo em baixas concentrações do herbicida. Nas maiores concentrações, E. densa mostrou maior sensibilidade que E. najas. O risco da aplicação do diquat para P. caudimaculatus foi estimado pela toxicidade aguda. Alevinos de P. caudimaculatus de 0,4 ± 0,2 mg foram expostos a soluções de 0,0; 1,0; 5,0; 10,0; 15,0; 20,0; 25,0; e 30,0 mg L-1 de diquat. A concentração letal de 50% (CL(I) (50;96h)) do diquat estimada para P. caudimaculatus foi de 7,17 mg L-1. Para P. caudimaculatus, a toxicidade aguda foi superior à concentração recomendada para o controle de macrófitas aquáticas submersas, indicando risco muito baixo para esse peixe.
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La course d’endurance active le système de récompense (SR) et est reliée aux comportements de recherche alimentaire. L’influence de la leptine sur l’activité physique (AP) volontaire est bien documentée d’un point de vue physiologique, mais très peu en termes d’impact hédonique. La leptine inhibe l’effet récompensant lié à la consommation de nourriture et joue un rôle semblable pour d’autres types de stimuli. La leptine s’arrime à la forme longue du récepteur à la leptine (Leprb) situé sur les neurones à dopamine (DA) et GABA de l’aire tegmentale ventrale (ATV) dans le mésencéphale. Signal transducer and Activator of Transcription 3 (STAT3) est un facteur de transcription important de la cascade de signalisation de la leptine. La phosphorylation de STAT3 n’est détectée que dans une parcelle des neurones DA positifs pour le Leprb, conférant aux neurones DA STAT3-spécifiques des caractéristiques uniques. Nous avons généré un modèle murin invalidé pour STAT3 sélectivement dans les neurones DA (STAT3DAT-KO). La première expérience consistait à évaluer les paramètres métaboliques de base de notre modèle en utilisant les chambres métaboliques Comprehensive Lab Animal Monitoring System (CLAMS), incluant l’activité ambulatoire, le ratio d’échanges respiratoires (RER) et la production de chaleur. Les STAT3DAT-KO sont hyperactives, démontré par une activité locomotrice augmentée, mais aucune variation entre les deux groupes n’est observée pour le RER et la production de chaleur, en plus d’un gain de poids identique. Une stratégie de récupération ciblant la réinsertion de STAT3 dans les neurones DA du système mésolimbique normalise l’AP anciennement plus élevée des STAT3DAT-KO à celle des contrôles, suivant l’accès libre à une roue d’exercice (RE) pour une durée de 4 semaines, suivant l’accès libre à une roue d’exercice (RE) pour une durée de 4 semaines. L’injection d’un psychostimulant (agoniste du récepteur DA de type 1 (D1R), le Chloro-APB-Hydrobromide (SKF 82958)) reflète une fonction dopaminergique réduite chez les STAT3DAT-KO. Un test de recherche compulsive de nourriture révèle une suppression de la prise alimentaire chez les deux groupes expérimentaux. Nous démontrons pour la première fois que la motivation alliée à la course d’endurance, indépendamment de la régulation de la prise alimentaire par la leptine, est dépendant d’une signalisation leptine-STAT3 amoindrie dans les neurones DA du système mésolimbique, révélant STAT3 comme élément clé dans la régulation du tonus dopaminergique et des propriétés récompensantes de l’AP.
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A life of piracy offered marginal men a profession with a degree of autonomy, despite the brand of “outlaw” and the fear of prosecution. At various times throughout history, governments and crowned heads suspended much of their piracy prosecution, licensing men to work as “privateers” for the state, supplementing naval forces. This practice has a long history, but in sixteenth-century England, Elizabeth I (1558-1603) significantly altered this tradition. Recognizing her own weakness in effectively prosecuting these men and the profit they could contribute to the government, Elizabeth began incorporating pirates into the English naval corps in peacetime—not just in war. This practice increased English naval resources, income, and presence in the emerging Atlantic World, but also increased conflict with the powerful Spanish empire. By 1605, making peace with Spain, James VI/I (1603-1625) retracted Elizabeth’s privateering promotion, prompting an emigration of English seamen to the American outposts they had developed in the previous century. Now exiles, no longer beholden to the Crown, seamen reverted back to piracy. The Carolinas and Jamaica served as bases for these rover communities. In 1650, the revolutionary leader Oliver Cromwell (1649-1658) once again recognized the merits of such policies. Determined to demonstrate his authority and solidify his rule, Cromwell offered citizenship and state support to Caribbean exiles in exchange for their aiding of his navy in the taking of Spanish Jamaica. Official chartering of Port Royal, Jamaica served as reward for these men’s efforts and as the culmination of a century-long cycle of piracy legislation, creating one of England’s most lucrative colonies in the middle of a traditionally Spanish Caribbean empire. Through legal and diplomatic records, correspondence, and naval and demographic records from England and Spain, this dissertation explores early modern piracy/privateering policy and its impact on the development of the Atlantic World. European disputes and imperial competition converged in these piracy debates with significant consequences for the definitions of criminality and citizenship and for the development of Atlantic empire.
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The role of the principal in school settings and the principal’s perceived effect on student achievement have frequently been considered vital factors in school reform. The relationships between emotional intelligence, leadership style and school culture have been widely studied. The literature reveals agreement among scholars regarding the principal’s vital role in developing and fostering a positive school culture. The purpose of this study was to explore the relationships between elementary school principals’ emotional intelligence, leadership style and school culture. The researcher implemented a non-experimental ex post facto research design to investigate four specific research hypotheses. Utilizing the Qualtrics Survey Software, 57 elementary school principals within a large urban school district in southeast Florida completed the Emotional Quotient Inventory (EQ-i), and 850 of their faculty members completed the Multifactor Leadership Questionnaire (MLQ Form 5X). Faculty responses to the school district’s School Climate Survey retrieved from the district’s web site were used as the measure of school culture. Linear regression analyses revealed significant positive associations between emotional intelligence and the following leadership measures: Idealized Influence-Attributes (β = .23, p = < .05), Idealized Influence-Behaviors (β = .34, p = < .01), Inspirational Motivation (β = .39, p = < .01) and Contingent Reward (β = .33, p = < .01). Hierarchical regression analyses revealed positive associations between school culture and both transformational and transactional leadership measures, and negative associations between school culture and passive-avoidant leadership measures. Significant positive associations were found between school culture and the principals’ emotional intelligence over and above leadership style. Hierarchical linear regressions to test the statistical hypothesis developed to account for alternative explanations revealed significant associations between leadership style and school culture over and above school grade. These results suggest that emotional intelligence merits consideration in the development of leadership theory. Practical implications include suggestions that principals employ both transformational and transactional leadership strategies, and focus on developing their level of emotional intelligence. The associations between emotional intelligence, transformational leadership, Contingent Reward and school culture found in this study validate the role of the principal as the leader of school reform.
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In multi-unit organisations such as a bank and its branches or a national body delivering publicly funded health or education services through local operating units, the need arises to incentivize the units to operate efficiently. In such instances, it is generally accepted that units found to be inefficient can be encouraged to make efficiency savings. However, units which are found to be efficient need to be incentivized in a different manner. It has been suggested that efficient units could be incentivized by some reward compatible with the level to which their attainment exceeds that of the best of the rest, normally referred to as “super-efficiency”. A recent approach to this issue (Varmaz et. al. 2013) has used Data Envelopment Analysis (DEA) models to measure the super-efficiency of the whole system of operating units with and without the involvement of each unit in turn in order to provide incentives. We identify shortcomings in this approach and use it as a starting point to develop a new DEA-based system for incentivizing operating units to operate efficiently for the benefit of the aggregate system of units. Data from a small German retail bank is used to illustrate our method.