235 resultados para Hypotheses


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This paper examines the effect of superstars on external stakeholders’ organizational identification through the lens of sport. Drawing on social identity theory and the concept of organizational identification, as well as on role model theories and superstar economics, several hypotheses are developed regarding the influence of soccer stars on their fans’ degree of team identification. Using a proprietary data set that combines archival data on professional German soccer players and clubs with survey data on more than 1,400 soccer fans, this study finds evidence for a positive effect of superstar characteristics and role model perception. Moreover, it is found that players who qualify for the definition of a superstar are more important to fans of established teams than to fans of unsuccessful teams. The player's club tenure, however, seems to have no influence on fans’ team identification. It is further argued that the effect of soccer stars on their fans is comparable to that of executives on external stakeholders, and hence, the results are applied to the business domain. The results of this study contribute to existing research by extending the list of personnel-related determinants of organizational identification.

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Purpose – The purpose of this paper is to examine the effect of superstars (and other factors) on football fans’ attraction to competition (i.e. disloyal behavior). Design/methodology/approach – A proprietary data set including archival data on professional German football players and clubs as well as survey data of more than 900 football fans is used. The hypotheses are tested with two-sample mean-comparison t-tests and multivariate probit models. Findings – This study provides evidence that superstars both attract new fans and contribute to the retention of existing fans. While the presence of superstars, team loyalty and team identification prevent football fans from being attracted to competition, the team's recent performance seems to have no effect. Fans who select their favorite player from a competing team rather choose superstars, young players, players who are known for exemplary behavior and defenders. Originality/value – This paper contributes to existing research by expanding the list of antecedents of disloyalty and by being the first to employ independent, quantitative data for the assessment of superstar characteristics in the context of team loyalty.

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Many insect clades, especially within the Diptera (true flies), have been considered classically ‘Gondwanan’, with an inference that distributions derive from vicariance of the southern continents. Assessing the role that vicariance has played in the evolution of austral taxa requires testing the location and tempo of diversification and speciation against the well-established predictions of fragmentation of the ancient super-continent. Several early (anecdotal) hypotheses that current austral distributions originate from the breakup of Gondwana derive from studies of taxa within the family Chironomidae (non-biting midges). With the advent of molecular phylogenetics and biogeographic analytical software, these studies have been revisited and expanded to test such conclusions better. Here we studied the midge genus Stictocladius Edwards, from the subfamily Orthocladiinae, which contains austral-distributed clades that match vicariance-based expectations. We resolve several issues of systematic relationships among morphological species and reveal cryptic diversity within many taxa. Time-calibrated phylogenetic relationships among taxa accorded partially with the predicted tempo from geology. For these apparently vagile insects, vicariance-dated patterns persist for South America and Australia. However, as often found, divergence time estimates for New Zealand at c. 50 mya post-date separation of Zealandia from Antarctica and the remainder of Gondwana, but predate the proposed Oligocene ‘drowning’ of these islands. We detail other such ‘anomalous’ dates and suggest a single common explanation rather than stochastic processes. This could involve synchronous establishment following recovery from ‘drowning’ and/or deleteriously warming associated with the mid-Eocene climatic optimum (hence ‘waving’, which refers to cycles of drowning events) plus new availability of topography providing of cool running waters, or all these factors in combination. Alternatively a vicariance explanation remains available, given the uncertain duration of connectivity of Zealandia to Australia–Antarctic–South America via the Lord Howe and Norfolk ridges into the Eocene.

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Population genetic studies of freshwater invertebrate taxa in New Zealand and South America are currently few despite the geologically and climatically dynamic histories of these regions. The focus of our study was a comparison of the influence on realized dispersal of 2 closely related nonbiting midges (Chironomidae) of population fragmentation on these separated austral land masses. We used a 734-base pair (bp) fragment of cytochrome c oxidase subunit I (COI) to investigate intraspecific genetic structure in Naonella forsythi Boothroyd in New Zealand and Ferringtonia patagonica Edwards in Patagonia. We proposed hypotheses about their potential dispersal and, hence, expected patterns of genetic structure in these 2 species based on published patterns for the closely related Australian taxon Echinocladius martini Cranston. Genetic structure revealed for both N. forsythi and F. patagonica was characterized by several highly divergent (2.0–10.5%) lineages of late Miocene–Pliocene age within each taxon that were not geographically localized. Many were distributed widely. This pattern differed greatly from population structure in E. martini, which was typified by much greater endemicity of divergent genetic lineages. Nevertheless, diversification of lineages in all 3 taxa appeared to be temporally congruent with the onset of late Miocene glaciations in the southern hemisphere that may have driven fragmentation of suitable habitat, promoting isolation of populations and divergence in allopatry. We argue that differences in realized dispersal post-isolation may be the result of differing availability of suitable habitat in interglacial periods.

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In the commercial food industry, demonstration of microbiological safety and thermal process equivalence often involves a mathematical framework that assumes log-linear inactivation kinetics and invokes concepts of decimal reduction time (DT), z values, and accumulated lethality. However, many microbes, particularly spores, exhibit inactivation kinetics that are not log linear. This has led to alternative modeling approaches, such as the biphasic and Weibull models, that relax strong log-linear assumptions. Using a statistical framework, we developed a novel log-quadratic model, which approximates the biphasic and Weibull models and provides additional physiological interpretability. As a statistical linear model, the log-quadratic model is relatively simple to fit and straightforwardly provides confidence intervals for its fitted values. It allows a DT-like value to be derived, even from data that exhibit obvious "tailing." We also showed how existing models of non-log-linear microbial inactivation, such as the Weibull model, can fit into a statistical linear model framework that dramatically simplifies their solution. We applied the log-quadratic model to thermal inactivation data for the spore-forming bacterium Clostridium botulinum and evaluated its merits compared with those of popular previously described approaches. The log-quadratic model was used as the basis of a secondary model that can capture the dependence of microbial inactivation kinetics on temperature. This model, in turn, was linked to models of spore inactivation of Sapru et al. and Rodriguez et al. that posit different physiological states for spores within a population. We believe that the log-quadratic model provides a useful framework in which to test vitalistic and mechanistic hypotheses of inactivation by thermal and other processes. Copyright © 2009, American Society for Microbiology. All Rights Reserved.

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Chlamydia trachomatis is the leading cause of bacterial sexually transmitted disease worldwide resulting in 4–5 million new cases of Chlamydia annually and an estimated 100 million cases per annum. Infections of the lower female genital tract (FGT) frequently are asymptomatic so they often remain undiagnosed or untreated. If infections are either not resolved, or are left untreated, chlamydia can ascend to the upper FGT and infect the fallopian tubes (FTs) causing salpingitis that may lead to functional damage of the FTs and tubal factor infertility (TFI). Clinical observations and experimental data have indicated a role for antibodies against C. trachomatis proteins such as the 60 kDa heat-shock protein 60 (cHSP60) in the immunopathogenesis of TFI. When released from infected cells cHSP60 can induce pro-inflammatory immune responses that may functionally impair the FTs leading to fibrosis and luminal occlusion. Chlamydial pathogenesis of irreversible and permanent tubal damage is a consequence of innate and adaptive host immune responses to ongoing or repeated infections. The extracellular matrix (ECM) that is regulated by metalloproteinases (MMPs) may also be modified by chlamydial infections of the FGT. This review will highlight protective and pathogenic immune responses to ongoing and repeated chlamydial infections of the FGT. It will also present two recent hypotheses to explain mechanisms that may contribute to FT damage during a C. trachomatis infection. If Chlamydia immunopathology can be controlled it might yield a method of inducing fibrosis and thus provide a means of non-surgical permanent contraception for women.

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This study examines how call centres adopt different types of human resource practices (involvement and control oriented) to manage frontline employees in Indian call centres. Data were collected from 250 call centre representatives to test the research hypotheses. The research model was analyzed using Mplus software. Findings showed that involvement and control oriented human resource practices resulted in more employee exhaustion and disengagement. Involvement oriented HRM had a positive impact on job satisfaction as well as, a positive relationship between employee exhaustion and disengagement. The findings suggest that, while involvement oriented HRM enhances job satisfaction, its implementation comes with a cost, that is, an increase in employee exhaustion and disengagement at work.

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Addiction is a devastating disorder that affects 15.3 million people worldwide. While prevalent, few effective treatments exist. Orexin receptors have been proposed as a potential target for anti-craving medications. Orexins, also known as hypocretins, are neuropeptides produced in neurons of the lateral and dorsomedial hypothalamus and perifornical area, which project widely throughout the brain. The absence of orexins in rodents and humans leads to narcolepsy. However, orexins also have an established role in reward seeking. This review will discuss some of the original studies describing the roles of the orexins in reward seeking as well as specific works that were presented at the 2013 International Narcotics Research Conference. Orexin signalling can promote drug-induced plasticity of glutamatergic synapses onto dopamine neurons of the ventral tegmental area (VTA), a brain region implicated in motivated behaviour. Additional evidence suggests that orexin signalling can also promote drug seeking by initiating an endocannabinoid-mediated synaptic depression of GABAergic inputs to the VTA, and thereby disinhibiting dopaminergic neurons. Orexin neurons co-express the inhibitory opioid peptide dynorphin. It has been proposed that orexin in the VTA may not mediate reward per se, but rather occludes the ‘anti-reward’ effects of dynorphin. Finally, orexin signalling in the prefrontal cortex and the central amygdala is implicated in reinstatement of reward seeking. This review will highlight recent work describing the role of orexin signalling in cellular processes underlying addiction-related behaviours and propose novel hypotheses for the mechanisms by which orexin signalling may impart drug seeking.

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Sexual segregation is best known in sexually dimorphic ungulates. Many hypotheses have been proposed to explain the evolution of sexual segregation in ungulates, but all are reducible to the influence of two factors: body size and sex-specific reproductive strategy. Definitive tests of these hypotheses are lacking in ungulates because these factors are confounded, all males being somewhat larger than females. Kangaroos represent a parallel radiation of terrestrial herbivores, but their populations are composed of a spectrum of adult body sizes, ranging from small males the same size as females to large males more than twice the size. We exploited this heteromorphism to assess the independent influences of size and sex in these ungulate analogues. We conducted a preliminary study of western grey kangaroos (Macropus fuliginosus) in north-western Victoria, Australia. Adult males predominately occupied grassland habitat, whereas females occurred mostly in lakebed, woodland and shrubland. Single-sex groups occurred more often than expected during the non-mating season. The diet of large males had the highest proportion of grass, and females had the least. These initial results indicate that both size and sex influence segregation in this species, confirming the worth of kangaroos as marsupial models for research into the evolution of sexual segregation.

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Do the political values of the general public form a coherent system? What might be the source of coherence? We view political values as expressions, in the political domain, of more basic personal values. Basic personal values (e.g., security, achievement, benevolence, hedonism) are organized on a circular continuum that reflects their conflicting and compatible motivations. We theorize that this circular motivational structure also gives coherence to political values. We assess this theorizing with data from 15 countries, using eight core political values (e.g., free enterprise, law and order) and ten basic personal values. We specify the underlying basic values expected to promote or oppose each political value. We offer different hypotheses for the 12 non-communist and three post-communist countries studied, where the political context suggests different meanings of a basic or political value. Correlation and regression analyses support almost all hypotheses. Moreover, basic values account for substantially more variance in political values than age, gender, education, and income. Multidimensional scaling analyses demonstrate graphically how the circular motivational continuum of basic personal values structures relations among core political values. This study strengthens the assumption that individual differences in basic personal values play a critical role in political thought.

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Purpose This study investigates the effects of service innovation exploration-exploitation on financial performance through the delivery of quality services. Additional emphasis is also given to examining the extent to which employee empowerment and slack resources enhance or suppress the performance benefits of service firms engaging in service innovation exploration versus exploitation. Design/methodology/approach Data were drawn from a multi-informant survey of service firms using a drop-and-collect approach. The survey gathered data from managers, customer service employees and customers to test the hypotheses. Findings The results show that excelling at both exploitative and exploratory innovation helps enhance the quality of services, which in turn yield superior financial performance. Further, empowering employees enhances the relationship between exploratory and exploitative service innovation and service quality. We also show that the extent managers’ perceived their market to be competitive influences in the pursuit of high levels of both service innovation exploration and exploitation and that this relationship is impacted by the extent they believe they have available slack resources. Practical implications The findings suggest that service firms need to pursue both exploitation and exploration at high levels simultaneously and empower their employees to stay ahead of competitors in delivering quality services, which ultimately contribute to the achievement of superior financial outcomes. Also, the findings highlight the importance of employee empowerment, market competitiveness and slack resources in the pursuit of high levels of both service innovation exploration and exploitation. Originality/value These findings and our theory indicate that this study is the first to empirically examine organizational ambidexterity in the context of service innovation exploration – exploitation adopting the principles of combined and balanced innovation. The study provides insights into the critical role of customers’ perceptions of service quality in contributing to firms’ financial performance. Our insights are unique in that the study incorporates managers, employees and customers in an integrated service innovation model.

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This chapter explores the possibility and exigencies of employing hypotheses, or educated guesses, as the basis for ethnographic research design. The authors’ goal is to examine whether using hypotheses might provide a path to resolve some of the challenges to knowledge claims produced by ethnographic studies. Through resolution of the putative division between qualitative and quantitative research traditions , it is argued that hypotheses can serve as inferential warrants in qualitative and ethnographic studies.

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This program of research investigated the harmful effects of mistreatment by the workgroup, and the role of perceived rejection as a critical mediator linking mistreatment and outcomes. This research program had three primary purposes. First, the research aimed to examine the important role of workgroup mistreatment as an independent predictor of negative outcomes, over and above the influence of supervisor mistreatment. Second, the research aimed to examine the effect of perceived rejection as an explanatory variable linking workgroup mistreatment and outcomes. Finally, the moderating effect of organizational norms on the relationship between workgroup mistreatment and perceived rejection was examined. The relationships of interest were examined over four studies, using multiple methods of data collection, across part-time and full-time working samples. In Study 1 (Chapter 2), the independent role of workgroup mistreatment and the mediating role of perceived rejection were examined. One hundred and forty two part-time working participants took part in the study. The participants completed a questionnaire on workplace behaviors in their organizations. The results of hierarchical regression analyses revealed a strong harmful effect of workgroup mistreatment, independent of mistreatment by the supervisor. In addition, the results showed that perceived rejection fully mediated the relationship between workgroup mistreatment and depression and organizational based self esteem. The study highlighted that perceived rejection acts as a key underlying psychological mechanism involved in the effect of workgroup mistreatment. This study has been published in the Journal of Occupational Health Psychology. Study 2 and Study 3 were presented as one paper in Chapter 3. The aims of these two studies was to explore the effects of workgroup mistreatment on a wider range of individual and organizational level outcomes, and to provide further evidence of the mediating role of perceived rejection as observed in Study 1. The results from both studies demonstrated that workgroup mistreatment had a significant and independent role in predicting negative individual and organizational level outcomes, providing support for the findings of Study 1. In the first study, 189 participants received scenarios manipulating workgroup mistreatment and supervisor mistreatment. The results of hierarchical regression analyses revealed that workgroup mistreatment harmfully affected participants, over and above that of the supervisor. The results also demonstrated that perceived rejection mediated the positive relationships between workgroup mistreatment and depression and organizational deviance, and also the negative relationships between workgroup mistreatment and organizational based self esteem and organizational citizenship behaviors. The second study included an additional aim, to examine the moderating role of supportive organizational norms. Two hundred and twenty nine participants read scenarios that manipulated workgroup mistreatment, supervisor mistreatment and organizational norms. The results of hierarchical regression analyses revealed the significant harmful effects of workgroup mistreatment, over and above the influence of supervisor mistreatment. The results also revealed the mediating role of perceived rejection. The direct effect of positive organizational norms also emerged, consistent with previous research. In addition, the result revealed that employees who experienced supportive organizational norms were more likely to reconcile with their workgroup members after experiencing mistreatment compared to employees who experienced hostile organizational norms. Finally, an unexpected pattern on the key affective variables of depression and organizational based self esteem emerged, such that mistreatment led to more negative outcomes in the supportive norms condition than in the hostile condition, where employees appeared to be desensitized. This paper is currently under review at the Journal of Applied Social Psychology. In Study 4 (Chapter 4), the overall model of workplace mistreatment was tested on a sample of full-time workers in an applied setting. One hundred and seventy two adults took part in the study. Participants were required to evaluate their workplace regarding mistreatment and organizational norms and to report their own psychological, behavioral and organizational outcomes. The results revealed that workgroup mistreatment was associated with increased depression, stress and avoidance, over and above supervisor mistreatment. In addition, the results revealed that perceived rejection acted as an explanatory variable linking workgroup mistreatment to a number of outcomes. Furthermore, the moderating role of hostile organizational norms emerged on depression, stress, reconciliation and avoidance. This paper is currently under review at the Journal of Occupational Health Psychology. Overall, the four studies provided empirical support for the majority of the hypotheses. The effects were demonstrated for a range of psychological, behavioral, and organizational level outcomes, using multiple methods of data collection, across part-time and full-time workers. At the conclusion of the thesis (Chapter 5), an overall summary is provided of the findings across all four studies, practical and theoretical implications and research directions.

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This article examines variations in performance between fast-growth – the so-called gazelle – firms. Specifically, we investigate how the level of growth affects future profitability and how this relationship is moderated by firm strategy. Hypotheses are developed regarding the moderated growth–profitability relationship and are tested using longitudinal data from a sample of 964 Danish gazelle firms. We find a positive relationship between growth and profitability among gazelle firms. This relationship is moderated, however, by market strategy; it is stronger for firms pursuing a broad market strategy rather than a niche strategy. This study contributes to the current literature by providing a more nuanced view of the growth–profitability relationship and investigating the potential for the future performance of gazelle firms.

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Context Older oncology patients have unique needs associated with the many physical, psychological,and social changes associated with the aging process. The mechanisms underpinning and the impact of these changes are not well understood. Identification of clusters of symptoms is one approach that has been used to elicit hypotheses about the biological and/or psychological basis for variations in symptom experiences. Objectives The purposes of this study were to identify and compare symptom clusters in younger (<60 years) and older ($60 years) patients undergoing cancer treatment. Methods. Symptom data from one Australian study and two U.S. studies were combined to conduct this analysis. A total of 593 patients receiving active treatment were dichotomized into younger (<60 years) and older ($60 years) groups. Separate exploratory factor analyses (EFAs) were undertaken within each group to identify symptom clusters from occurrence ratings of the 32 symptoms assessed by the Memorial Symptom Assessment Scale. Results In both groups, a seven-factor solution was selected. Four partially concordant symptom clusters emerged in both groups (i.e., mood/cognitive, malaise, body image, and genitourinary). In the older patients, the three unique clusters reflected physiological changes associated with aging, whereas in the younger group the three unique clusters reflected treatment-related effects. Conclusion The symptom clusters identified in older patients typically included a larger and more diverse range of physical and psychological symptoms. Differences also may be reflective of variations in treatment approaches between age groups. Findings highlight the need for better understanding of variation in treatment and symptom burden between younger and older adults with cancer.