33 research outputs found

    The Value of Moderate Obsession: Insights from a New Model of Organizational Search

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    This study presents a new model of search on a “rugged landscape,” which employs modeling techniques from fractal geometry rather than the now-familiar NK modeling technique. In our simulations,firms search locally in a two-dimensional fitness landscape, choosing moves in a way that responds both to local payoff considerations and to a more global sense of opportunity represented by a firm-specific “preferred direction.” The latter concept provides a very simple device for introducing cognitive or motivational considerations into the formal account of search behavior, alongside payoff considerations. After describing the objectives and the structure of the model, we report a first experiment which explores how the ruggedness of the landscape affects the interplay of local payoff and cognitive considerations (preferred direction) in search. We show that an intermediate search strategy, combining the guidance of local search with a moderate level of non-local “obsession,” is distinctly advantageous in searching a rugged landscape. We also explore the effects of other considerations, including the objective validity of the preferred direction and the degree of dispersion of firm strategies. We conclude by noting available features of the model that are not exercised in this experiment. Given the inherent flexibility of the model, the range of questions that might potentially be explored is extremely large.Rugged Landscapes; Local Search; Cognition; Obsession; Fractal Geometry

    Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).

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    Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and ≄1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (n = 5069) or prospectively (n = 5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (≀6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; p = 0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)

    Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

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    BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

    Parents\u27 moral intentions towards antisocial parent behaviour: An identity approach in youth sport

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    2020 Elsevier Ltd Objectives: Grounded in personal and social identity theory, the purpose of this study was to examine whether parents\u27 personal and social identity perceptions influence their moral intentions towards antisocial parent behaviour in a youth sport setting. Design: Parents of competitive youth ice hockey players (N = 437) read a vignette that either described a parent from the participant\u27s own team (i.e., ingroup), or a parent from an opposing team (i.e., outgroup) acting antisocially towards an athlete from the participant\u27s own team, an opposing athlete, or their own child. Parents were asked whether they would respond to the antisocial behaviour in the form of direct or indirect criticism or report the behaviour to the coach or to the league. Results: Parents were more likely to directly criticize ingroup parents than outgroup parents and they were more likely to indirectly criticize outgroup parents than ingroup parents. Further, parents with stronger social identities reported higher intentions to indirectly criticize an outgroup parent. There were no main effects for reporting behaviour (to coach or league), and personal identity did not moderate relationships with moral intentions towards antisocial behaviour. Conclusion: By providing parents with a situation that includes antisocial parent behaviour in the immediate youth sport environment, novel insight was gathered with regard to what contextual elements might drive parents\u27 intention to criticize, but not report antisocial behaviour

    Parents’ Moral Intentions Towards Antisocial Parent Behaviour: An Identity Approach in Youth Sport

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    Objectives: Grounded in personal and social identity theory, the purpose of this study was to examine whether parents’ personal and social identity perceptions influence their moral intentions towards antisocial parent behaviour in a youth sport setting. Design: Parents of competitive youth ice hockey players (N = 437) read a vignette that either described a parent from the participant’s own team (i.e., ingroup), or a parent from an opposing team (i.e., outgroup) acting antisocially towards an athlete from the participant’s own team, an opposing athlete, or their own child. Parents were asked whether they would respond to the antisocial behaviour in the form of direct or indirect criticism or report the behaviour to the coach or to the league. Results: Parents were more likely to directly criticize ingroup parents than outgroup parents and they were more likely to indirectly criticize outgroup parents than ingroup parents. Further, parents with stronger social identities reported higher intentions to indirectly criticize an outgroup parent. There were no main effects for reporting behaviour (to coach or league), and personal identity did not moderate relationships with moral intentions towards antisocial behaviour. Conclusion: By providing parents with a situation that includes antisocial parent behaviour in the immediate youth sport environment, novel insight was gathered with regard to what contextual elements might drive parents’ intention to criticize, but not report antisocial behaviour
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