Repetitive stress injuries are common in the workplace where workers perform repetitive tasks continuously throughout the day. Muscle fatigue may lead to injury either directly through muscle damage or indirectly through changes in coordination, development of muscle imbalances, kinematic and muscle activation variability, and/or movement instability. To better understand the role of muscle fatigue in changes in movement parameters, we studied how muscle fatigue and muscle imbalances affected the control of movement timing, variability, and stability during a repetitive upper extremity sawing task. Since muscle fatigue leads to delayed muscle and cognitive response times, we might expect the ability to maintain movement timing would decline with muscle fatigue. We compared timing errors pre- and post-fatigue as subjects performed this repetitive sawing task synchronized with a metronome using standard techniques and a goal-equivalent manifold (GEM) approach. No differences in basic performance parameters were found. Significant decreases in the temporal correlations of the timing errors and velocities indicated that subjects made more frequent corrections to their movements post-fatigue. Muscle fatigue may lead to movement instability through a variety of mechanisms including delayed muscle response times and muscle imbalances. To measure movement stability, we must first define a state space that describes the movement. We compared a variety of different state space definitions and found that state spaces composed of angles and velocities with little redundant information provide the most consistent results. We then studied the affect of fatigue on the shoulder flexor muscles and general fatigue of the arm on movement stability. Subjects were able to maintain stability in spite of muscle fatigue, shoulder strength imbalance and decreased muscle cocontraction. Little is known about the time course for adaptations in response to fatigue. We studied the effect of muscle fatigue on movement coordination, kinematic variability and movement stability while subjects performed the same sawing task at two work heights. Increasing the height of the task caused subjects to make more adjustments to their movement patterns in response to muscle fatigue. Subjects also exhibited some increases in kinematic variability at the shoulder but no changes in movement stability. These findings suggest that people alter their kinematic patterns in response to fatigue possibly to maintain stability at the expense of increased variability. / text

The purpose of this dissertation was to investigate the differential effects of goal setting and value reappraisal on female students’ self-efficacy beliefs, value perceptions, exam performance and continued interest in statistics. It was hypothesized that the Enhanced Goal Setting Intervention (GS-E) would positively impact students’ self-efficacy beliefs and exam performance, whereas the Enhanced Value-Reappraisal (VR-E) was expected to positively affect students’ value perceptions and continued interest in learning statistics. A total of 88 female undergraduate students enrolled in two sections of an introductory statistics course completed the entire study. Students were primarily Caucasian, upper division, and traditionally aged. Students were stratified on course section and year in school and randomly assigned to one of three groups: Control Group (n=30); GS-E Group (n=27); and VR-E (n=31). GS-E asked students to both set and self-evaluate eight goals focused on reaching learning objectives for their upcoming statistics exam. VR-E presented students with messages about why learning statistics could be important for them and guided them in processing these messages. The Control Condition asked students to complete three Texas Information Literacy Tutorial modules and answer reflective questions. Findings from this dissertation partially supported the hypotheses related to VR-E, but no support was found for the hypotheses related to GS-E. The VR-E Intervention was found to positively impact measures of students’ value perceptions and continued interest. Immediate effects of VR-E were observed on: 1) the overall value students placed on learning statistics; 2) students’ interest and enjoyment of statistics; 3) the importance students placed on developing statistical knowledge and skills for the attainment of their future goals; and 4) students’ intentions to continue learning statistics on their own. However, relatively stronger and longer-lasting effects were observed on the later two variables. Also, students in the VR-E Group outperformed students in the GS-E Group on their post-intervention exam; however, neither group was significantly different from the Control Group. Findings from this research help to address the growing economic and social needs for the development and evaluation of theory-based educational interventions that target the improvement of college students’ achievement and continued interest in math and science education. / text

While a substantial body of research has documented how consumers' levels of progress, in general, influence their motivation in goal pursuit, the changes in the determinants of motivation in different stages of goal pursuit and their impact on consumers' self-regulation remain largely unexplored. Specifically, what are the factors consumers focus on when they first start to pursue a goal versus when they are approaching the end point of the pursuit? My dissertation explores this important question from three different angles: the perceived velocity, the mental representation of progress level, and the perceived closeness with others who are pursuing the same goal. Through three essays, we found that when people first begin to pursue a goal and the attainability of the goal is a concern, they are motivated by a fast speed of progressing, tend to exaggerate the progress they have made so far, and seek companionship from others who are pursuing the same goal, to enhance the belief that the goal is indeed attainable. However, once they reach the advanced stage of the pursuit and the attainability of the goal is relatively secured, they switch to focus on the remaining discrepancy and seek to reduce this gap in a timely manner; therefore, in this advanced stage of the pursuit they are conversely motivated by a slow speed of progressing, tend to downplay the progress they have made to exaggerate the remaining discrepancy that still needs to be completed, and such intense progress monitoring also leads to competitiveness against others who are pursuing the same goal as them. / text

De nos jours, l'entreprise est devenue un monde complexe où se côtoient une multitude de processus plus ou moins formalisés et un ensemble de règles de fonctionnement tacites ou écrites. Selon cette nouvelle organisation, la panne d'un équipement, l'indisponibilité d'une source d'énergie, l'arrêt d'un système automatique, les accidents sont de moins en moins tolérables. Pour ce faire la Fiabilité est maintenant une science qu'aucun concepteur de produit ou d'installation ne peut ignorer. Cependant, l'adoption de la fiabilité limitée sur l'analyse systémique pour la prévision des risques souffre du manque de prise en compte de la variabilité des situations de travail. Cette variabilité se manifeste par la présence de l'opérateur humain comme le postulat de base de l'apparition des événements et des grandes catastrophes des défaillances. En effet, la fiabilité humaine mérite une attention particulière, pourvu que l'opérateur est considéré au coeur du système de travail, il est doublement concerné, donc il est primordial d'appliquer des méthodes pour quantifier son comportement. Dans de telles situations nous proposons d'appliquer un modèle d'optimisation de la fiabilité humaine sous l'initiative de minimisation des risques professionnels par application du modèle programmation mathématique multicritère : Goal Programming avec les fonctions de satisfactions. L'analyse sur le terrain est probante, puisqu'elle permet d'expérimenter le modèle proposé. C'est pourquoi l'étude expérimentale du modèle d'optimisation de la fiabilité humaine est réalisée dans une industrie de traitement de Gaz.

This dissertation develops the Focus Theory of Group Productivity, describes the use of the theory to guide development of several electronic group support tools, and reports the results of experiments testing whether the tools yield the predicted productivity gains. Focus theory posits that to be productive group members must divide their attention between three cognitive processes: communication, Deliberation, and information access. Communication, Deliberation, and information access are, in turn, constrained by limited attention and fading memory. Finally group members are only willing to engage their attention resources to the extent that the group goal is congruent with their individual goals. Electronic tools can reduce the attention demand of each of the three cognitive processes, and focus participant attention on appropriate problem-solving behaviors. Electronic tools can foster goal congruence under some circumstances. This dissertation describes how Focus Theory guided the development of the several electronic tools to support the needs of real groups experiencing real productivity problems. It reports the results of several laboratory experiments to test the goal-congruence hypothesis of Focus Theory. The first experiment frames social loafing and social comparison as goal congruence issues, showing that subjects using a real-time graph to compare their own performance to that of an average group generated more unique ideas than a group with no basis for comparison. Facilitation techniques boosted the salience of the comparison, further increasing performance. The second study frames affective reward as a goal congruence issue and develops and validates a measure for the construct. The third study frames user interface design in terms of goal congruence and demonstrates the strengths (pointing, selecting, moving, fine motor control) and weaknesses (handwriting recognition) of pen-based interfaces in those terms. The fourth study frames the classroom as a group-productivity setting and demonstrates that group support systems can be used to improve classroom interactions.

Convergent evidence suggests that the dorsal medial prefrontal cortex (dmPFC) makes an important contribution to goal-directed action selection. The dmPFC is also part of a network of brain regions that becomes compromised in old age. It was hypothesized that during decision-making, some process of comparison takes place in the dmPFC between the representation of available actions and associated values, and that this process is changed with aging. These hypotheses were tested in aged and young adult rats performing a novel 3-choice, 2-cue decision task. Neuron and local field potential activity revealed that the dmPFC experienced different states during decision and outcome phases of the task, with increased local inhibition and oscillatory (gamma and theta) activity during cue presentation, and increased excitatory neuron activity (among regular firing neurons) at goal zones. Although excitatory and inhibitory activity appeared anti-correlated over phases of the decision task, cross-correlations and the prominent gamma oscillation revealed that excitation and inhibition were highly correlated on the millisecond scale. This "micro-scale" coupling between excitation and inhibition was altered in aged rats and the observed changes were correlated with changes in decision and movement speeds of the aged animals, suggesting a putative mechanism for age-related behavioral slowing. With respect to decision-making, both aged and young adult rats learned over multiple days to follow the rewarded cue in the 3-choice, 2-cue task. Support for the hypothesis that the dmPFC simultaneously represents alternative actions was not found; however, neuron activity selective for particular goal zones was observed. Interestingly, goal-selective neural activity during the decision period was more likely to take place on error trials, particularly on high-performing sessions and when rats exhibited a preference for a particular feeder. A possible interpretation of these patterns is that goal representations in the dmPFC might have sometimes overruled learned habits, which are likely to be involved in following the correct cue and which are known to be supported by other brain regions. These results describe fundamental properties of network dynamics and neural coding in the dmPFC, and have important implications for the neural basis of processing speed and goal-directed action.

Self-regulation and self-control are motivational constructs involved in the process of goal pursuit (Karoly, 1993). Although investigators within and across various fields of psychology have used the terms interchangeably (e.g., Hofmann, Rauch, & Gawronski, 2007; Lord, Diefendorff, Schmidt, & Hall, 2009; Wood, 2005), theoretical work stemming from the clinical field suggests that they are distinct yet related constructs (e.g., F. Kanfer, 1970, 1977; F. Kanfer & Karoly, 1972). However, until now, the relationship between self-regulation and self-control had not been investigated empirically. In the current program of research, I delineated their relationship in two ways. First, I developed and evaluated new self-report measures that better match theoretical models of self-regulation and self-control. Participants (N = 199) completed a battery of self-report questionnaires regarding personality, motivation, self-regulation, and self-control. The new measures had acceptable internal consistency and test-retest reliabilities, and displayed relationships expected for convergent and discriminant validity. Modeling techniques indicated that self-control and self-regulation are not strongly enough associated to fall under one higher-order factor, and that the relationship between the two constructs was best represented by a model in which self-control was associated with the self-regulatory stage of goal striving. Second, I evaluated the efficacy of a training session that included self-control techniques in addition to self-regulation skills, and compared outcomes to those from a self-regulation only training group, and a control group. One sample of undergraduate students (N = 49) and one sample of day-shift employees (N=41) were included. Participants completed questionnaires twice daily for a period of three weeks to report sleep-wake behavior, fatigue, affect, and productivity. Objective sleep measures also were obtained through the use of actigraphs, which monitor sleep-wake activity. The self-regulation training groups showed better goal adherence following the intervention compared to the control group, and the combined training groups had even better goal adherence than the self-regulation group. Positive affective changes were also reported among the training groups following the study period. The development of new measurement and training techniques, which better align with the theoretical formulations of self-regulation and self-control, will help to advance the theoretical work concerning these constructs, and could lead to improvement in workplace outcomes.

Paskolų teikimas yra viena pagrindinių kredito unijų veiklos krypčių, o pagrindinė ir svarbiausia rizika su kuria jos susiduria yra būtent kredito rizika, todėl būtina ją detaliai analizuoti ir turėti patikimą šių aktyvų valdymo mechanizmą. Taip pat valdant, šią riziką, būtina atsižvelgti į socialinį kredito unijų aspektą. Darbo objektas – kredito rizikos valdymas. Darbo tikslas - išnagrinėti kredito unijų, kaip specifinių finansinių institucijų, veiklos ir kredito rizikos valdymo ypatumus. Pirmoje darbo dalyje nagrinėjami kredito unijų kredito rizikos valdymo ypatumai: analizuojama kooperatyvinių finansinių institucijų kreditavimo specifika bei kredito rizikos ypatybės būdingos kredito unijoms. Taip pat apžvelgiami kredito rizikos vertinimo principai ir pateikiami kredito rizikos valdymo metodai bei jų veikimo ypatybės. Antroje darbo dalyje analizuojama ir apibendrinama kredito rizikos valdymo kredito unijose praktika ir empiriniai tyrimai, apibūdinamos Lietuvos kredito unijų sektoriaus veiklos sąlygos ir formuojama kredito rizikos valdymo Lietuvos kredito unijose tyrimo metodika. Trečioje dalyje tiriami ir vertinami dviejų kredito unijų paskolų portfelio kokybės rodikliai, analizuojama paskolų portfelio koncentracija, remiantis atlikta analize formuojami efektyvūs Lietuvos kredito unijų investiciniai portfeliai, kaip kredito rizikos valdymo instrumentai. Pateikiami siūlymai geresniam kredito rizikos valdymo vystymui Lietuvos kredito unijose. Darbe prieita prie tokių... [toliau žr. visą tekstą] / Lending is one of the main credit union activities, and the most important risks which they face to is credit risk, it is necessary to analyze it in detail and have a sound mechanism of these asset management. As well as the management, this risk is necessary to consider the social aspect of the credit union. The work item - credit risk management. The aim - to examine the operational and credit risk management features of credit union as a specific financial institutions. The first part of the study looked at the credit union theoretical credit risk management features: characterized by cooperative financial institutions lending and credit risk perception of the concept of inherent credit unions. It also reviews the credit risk assessment principles and provides credit risk management techniques and performance characteristics. Secound segment of the paper characterizes situation in Lithuanian credit unions sector and describes researches based on credit risk management in credit unions practice. There also is given research method of credit risk management in Lithuanian credit unions. The work led to the following main conclusions. Credit union is a lending institution which distinguished higher degree of confidence and a wider access to financial services. Profitability is not as much emphasis to be exposed to liberal lending policies, fulfilling the mission and goals. Credit risk assessment before issuing a loan is the most important step in credit risk management process... [to full text]

The common view of brand choice in consumer marketing is that brands compete against each other within a specified product category. For example, different coffee brands are compared and evaluated by consumers and the most preferred brand is selected. Is this the only adequate way of demonstrating how consumers make brand choices? This thesis challenges the common view on brand choice and brand choice determinants in consumer markets on several accounts. First, brand choice is made in goal-derived categories (e.g., "foods to eat while on a diet"), and research on goal-derived categories and consumption goals suggests that consumers often choose between brands from different product categories. For example, a consumer may choose between brands of coffee, tea, and soft drinks to fulfill a consumption goal. Second, there is the question of complementarity. Are brands always chosen one by one? We argue in this thesis that consumers often choose brand constellations from complementary product categories in goal-derived categories (e.g., hamburgers and soft drinks when on a short lunch break). The thesis consists of four articles based on empirical studies. The articles cover single-brand choice and brand constellation choice in goal-derived categories, and the use of goal-derived categories by marketing practitioners. The general conclusion is that consumers evaluate more aspects than just brand-related ones when they choose brands in goal-derived categories. Product category associations (i.e., how typical a product category is perceived in a goal-derived category) are a more important determinant of brand (constellation) choice than brand associations. Also, in brand constellation choice, complementarity (i.e., perceived fit between brands) is more strongly related to brand choice than attitude towards individual brands. / <p>Diss. Stockholm : Handelshögsk., 2003</p>

This study examined the effects of visual statistics software on undergraduate students’ achievement in elementary statistics and the role of cognitive and non-cognitive factors in their achievement. An experimental design was implemented using ViSta – a visual statistics program. A sample of 273 undergraduate students at a leading, urban, southeastern research university enrolled in six sections of Elementary Statistics were selected and randomly assigned to experimental and comparison groups. The participants completed four surveys, with pre and post-test measures, which assessed their attitudes, statistics self-efficacy, perceptions of their learning environment, and statistical reasoning abilities. To further guide this study, the modified trichotomous framework (Beyth-Marom, Fidler, & Cumming, 2008; Elliot & McGregor, 2001) of goals, cognition, and achievement was used as the theoretical foundation to categorize the cognitive and non-cognitive predictors in relation to student achievement. Two quantitative data analysis methods were utilized. Mann-Whitney tests were employed to determine if there were any statistically significant differences in overall achievement and cognitive and non-cognitive sub-scales between the experimental and comparison groups. Correlation analysis was used to determine if there were any statistically significant associations between the overall grade in the course and the cognitive and non-cognitive sub-scales. For the qualitative data, error analysis was used to determine any underlying processes or misconceptions evident in students’ problem-solving application. Additionally, reliability analysis determined the internal consistency of the data and fidelity of implementation analysis ensured that the intervention was being applied appropriately. In this study, no statistically significant differences in achievement were noted. However, a significant difference was noted in students’ statistics self-efficacy between the comparison and experimental groups. Finally, using the Pearson product moment correlation (r), a statistically significant correlation was found between the overall grade and attitudes towards the course, attitudes towards statistics in the field, interpreting and applying statistical procedures, identifying scales of measurement, and the negotiation scale of students’ learning environment. In order to improve undergraduate statistics instruction, it was recommended that classes should involve more face-to-face engagement with the instructor, focus more on student-centered practices through the use of interactive technology, and incorporate activities from a variety of disciplines.