49 research outputs found

    Using The Censored Gamma Distribution for Modeling Fractional Response Variables with an Application to Loss Given Default

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    Regression models for limited continuous dependent variables having a non-negligible probability of attaining exactly their limits are presented. The models differ in the number of parameters and in their flexibility. Fractional data being a special case of limited dependent data, the models also apply to variables that are a fraction or a proportion. It is shown how to fit these models and they are applied to a Loss Given Default dataset from insurance to which they provide a good fit

    A dynamic nonstationary spatio-temporal model for short term prediction of precipitation

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    Precipitation is a complex physical process that varies in space and time. Predictions and interpolations at unobserved times and/or locations help to solve important problems in many areas. In this paper, we present a hierarchical Bayesian model for spatio-temporal data and apply it to obtain short term predictions of rainfall. The model incorporates physical knowledge about the underlying processes that determine rainfall, such as advection, diffusion and convection. It is based on a temporal autoregressive convolution with spatially colored and temporally white innovations. By linking the advection parameter of the convolution kernel to an external wind vector, the model is temporally nonstationary. Further, it allows for nonseparable and anisotropic covariance structures. With the help of the Voronoi tessellation, we construct a natural parametrization, that is, space as well as time resolution consistent, for data lying on irregular grid points. In the application, the statistical model combines forecasts of three other meteorological variables obtained from a numerical weather prediction model with past precipitation observations. The model is then used to predict three-hourly precipitation over 24 hours. It performs better than a separable, stationary and isotropic version, and it performs comparably to a deterministic numerical weather prediction model for precipitation and has the advantage that it quantifies prediction uncertainty.Comment: Published in at http://dx.doi.org/10.1214/12-AOAS564 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

    Using the Censored Gamma Distribution for Modeling Fractional Response Variables with an Application to Loss Given Default

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    Regression models for limited continuous dependent variables having a non-negligible probability of attaining exactly their limits are presented. The models differ in the number of parameters and in their flexibility. Fractional data being a special case of limited dependent data, the models also apply to variables that are a fraction or a proportion. It is shown how to fit these models and they are applied to a Loss Given Default dataset from insurance to which they provide a good fi

    Problems with Using the Normal Distribution – and Ways to Improve Quality and Efficiency of Data Analysis

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    Background: The Gaussian or normal distribution is the most established model to characterize quantitative variation of original data. Accordingly, data are summarized using the arithmetic mean and the standard deviation, by x 6 SD, or with the standard error of the mean, x 6 SEM. This, together with corresponding bars in graphical displays has become the standard to characterize variation. Methodology/Principal Findings: Here we question the adequacy of this characterization, and of the model. The published literature provides numerous examples for which such descriptions appear inappropriate because, based on the ‘‘95 % range check’’, their distributions are obviously skewed. In these cases, the symmetric characterization is a poor description and may trigger wrong conclusions. To solve the problem, it is enlightening to regard causes of variation. Multiplicative causes are by far more important than additive ones, in general, and benefit from a multiplicative (or log-) normal approach. Fortunately, quite similar to the normal, the log-normal distribution can now be handled easily and characterized at the level of the original data with the help of both, a new sign, x /, times-divide, and notation. Analogous to x 6 SD, it connects the multiplicative (or geometric) mean x * and the multiplicative standard deviation s * in the form x * x /s*, that is advantageous and recommended. Conclusions/Significance: The corresponding shift from the symmetric to the asymmetric view will substantially increas

    Correction to: Two years later: Is the SARS-CoV-2 pandemic still having an impact on emergency surgery? An international cross-sectional survey among WSES members

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    Background: The SARS-CoV-2 pandemic is still ongoing and a major challenge for health care services worldwide. In the first WSES COVID-19 emergency surgery survey, a strong negative impact on emergency surgery (ES) had been described already early in the pandemic situation. However, the knowledge is limited about current effects of the pandemic on patient flow through emergency rooms, daily routine and decision making in ES as well as their changes over time during the last two pandemic years. This second WSES COVID-19 emergency surgery survey investigates the impact of the SARS-CoV-2 pandemic on ES during the course of the pandemic. Methods: A web survey had been distributed to medical specialists in ES during a four-week period from January 2022, investigating the impact of the pandemic on patients and septic diseases both requiring ES, structural problems due to the pandemic and time-to-intervention in ES routine. Results: 367 collaborators from 59 countries responded to the survey. The majority indicated that the pandemic still significantly impacts on treatment and outcome of surgical emergency patients (83.1% and 78.5%, respectively). As reasons, the collaborators reported decreased case load in ES (44.7%), but patients presenting with more prolonged and severe diseases, especially concerning perforated appendicitis (62.1%) and diverticulitis (57.5%). Otherwise, approximately 50% of the participants still observe a delay in time-to-intervention in ES compared with the situation before the pandemic. Relevant causes leading to enlarged time-to-intervention in ES during the pandemic are persistent problems with in-hospital logistics, lacks in medical staff as well as operating room and intensive care capacities during the pandemic. This leads not only to the need for triage or transferring of ES patients to other hospitals, reported by 64.0% and 48.8% of the collaborators, respectively, but also to paradigm shifts in treatment modalities to non-operative approaches reported by 67.3% of the participants, especially in uncomplicated appendicitis, cholecystitis and multiple-recurrent diverticulitis. Conclusions: The SARS-CoV-2 pandemic still significantly impacts on care and outcome of patients in ES. Well-known problems with in-hospital logistics are not sufficiently resolved by now; however, medical staff shortages and reduced capacities have been dramatically aggravated over last two pandemic years

    Diversity and ethics in trauma and acute care surgery teams: results from an international survey

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    Background Investigating the context of trauma and acute care surgery, the article aims at understanding the factors that can enhance some ethical aspects, namely the importance of patient consent, the perceptiveness of the ethical role of the trauma leader, and the perceived importance of ethics as an educational subject. Methods The article employs an international questionnaire promoted by the World Society of Emergency Surgery. Results Through the analysis of 402 fully filled questionnaires by surgeons from 72 different countries, the three main ethical topics are investigated through the lens of gender, membership of an academic or non-academic institution, an official trauma team, and a diverse group. In general terms, results highlight greater attention paid by surgeons belonging to academic institutions, official trauma teams, and diverse groups. Conclusions Our results underline that some organizational factors (e.g., the fact that the team belongs to a university context or is more diverse) might lead to the development of a higher sensibility on ethical matters. Embracing cultural diversity forces trauma teams to deal with different mindsets. Organizations should, therefore, consider those elements in defining their organizational procedures. Level of evidence Trauma and acute care teams work under tremendous pressure and complex circumstances, with their members needing to make ethical decisions quickly. The international survey allowed to shed light on how team assembly decisions might represent an opportunity to coordinate team member actions and increase performance

    Photodissociation and photoionisation of atoms and molecules of astrophysical interest

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    Robust alternatives to least squares

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    Respiratory responses during affective picture viewing

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    Previous research has demonstrated covariation of physiological responding with judgments of valence and arousal. However, until now links between these affective dimensions and respiratory measures have not been extensively investigated. In this study, eight picture series of different affective valence and arousal level were shown to 30 subjects, while respiration, skin conductance level (SCL), heart rate (HR) and affective judgments were measured. With increasing pleasantness, inspiratory time lengthened, mean inspiratory flow decreased and thoracic breathing increased. With increasing arousal, inspiratory time and total breath duration shortened and mean inspiratory flow, minute ventilation, thoracic breathing and electrodermal activity increased. These findings confirm the importance of arousal in respiratory responding, but also indicate a modulatory role of affective valence.We propose that the arousal effects reflect energy mobilization in preparation to act, and thatthe valence effects might be a manifestation of an attention bias toward negative stimuli. [Authors]]]> eng oai:serval.unil.ch:BIB_4350 2022-02-19T02:20:17Z <oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"> https://serval.unil.ch/notice/serval:BIB_4350 ElĂšves en difficultĂ©s: la pĂ©dagogie compensatoire est-elle efficace ? Doudin, PA info:eu-repo/semantics/article article 1996 Psychoscope, vol. 9, pp. 4-7 oai:serval.unil.ch:BIB_43500F74D76A 2022-02-19T02:20:17Z <oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"> https://serval.unil.ch/notice/serval:BIB_43500F74D76A The Apostle Philip, The Viper, The Leopard, and the Kid. The Masked Actors of a Religious Conflict in Hierapolis of Phrygia (Acts of Philip VIII-XV and Martyrdom) Amsler, FrĂ©dĂ©ric info:eu-repo/semantics/conferenceObject inproceedings 1996 Society of Biblical Literature 1996 Seminar Papers, pp. 432-437 eng oai:serval.unil.ch:BIB_4350488D87C6 2022-02-19T02:20:17Z ehelvetica openaire documents phdthesis urnserval <oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"> https://serval.unil.ch/notice/serval:BIB_4350488D87C6 Etude du respect des mesures de prĂ©vention de la transmission verticale du virus de l'hĂ©patite B chez les enfants nĂ©s dans les maternitĂ©s des hĂŽpitaux publics du canton de Vaud Guidon-Nidecker, M. UniversitĂ© de Lausanne, FacultĂ© de biologie et mĂ©decine info:eu-repo/semantics/doctoralThesis phdthesis 2013 <![CDATA[Actuellement, en Suisse, environ 1% des femmes en Ăąge de procrĂ©er ont une hĂ©patite B chronique(8). En l'absence de mesures de prĂ©vention, le risque de transmission du virus de l'hĂ©patite B, de la mĂšre Ă  son enfant, est estimĂ© Ă  40%(3,4,5) lors de l'accouchement. Ce risque s'Ă©tend bien au-delĂ  de la pĂ©riode pĂ©riÂŹnatale. Les enfants infectĂ©s dans ces circonstances ont une probabilitĂ© de 90% de dĂ©velopper une infection chronique(5,7) et un quart meurent prĂ©maturĂ©ment de cirrhose ou d'hĂ©patocarcinome(2). L'Office fĂ©dĂ©ral de la santĂ© publique recommande d'effectuer un dĂ©pistage antĂ©natal de l'antigĂšne HBsAg lors de toute grossesse(1) et d'effectuer une vaccination passive et active chez tous les enfants naissant d'une mĂšre avec une hĂ©patite B chronique. Cette prophylaxie doit ĂȘtre effectuĂ©e comme suit : immunoglobuline spĂ©cifique et lere dose de vaccin dans les 12 heures suivant la naissance (en maternitĂ©) ; 2eme dose de vaccin Ă  1 mois, 3eme dose de vaccin Ă  6 mois et contrĂŽle de la rĂ©ponse immune entre le 7eme et le 12eme mois (par le mĂ©decin traitant). Cette Ă©tude vise Ă  Ă©valuer la compliance du systĂšme de soins envers ces recommandations qui exigent l'intervention des maternitĂ©s et des mĂ©decins traitants et qui s'Ă©talent dans le temps. Pour ce faire, un recensement rĂ©trospectif des enfants nĂ©s de mĂšre avec une hĂ©patite B chronique, en 2005 et 2006 dans 4 maternitĂ©s vaudoises, a Ă©tĂ© effectuĂ©. Les mesures appliquĂ©es par les maternitĂ©s, les informations transmises aux mĂ©decins traitants et les mesures appliquĂ©es par ces derniers ont Ă©tĂ© Ă©valuĂ©es. Sur un total de 10'412 parturientes testĂ©es, 70 prĂ©sentent une infection chronique et 51 acceptent le recrutement dans l'Ă©tude (reprĂ©sentant un collectif de 54 enfants). En maternitĂ©, l'immunisation active et passive est effectuĂ©e chez tous les enfants. L'Ă©vidence qu'elle est effectuĂ©e dans les 12 heures suivant la naissance est fournie dans 61% des cas (mais dans 100% des dossiers dans lequel ce renseignement est consignĂ©). La nĂ©cessitĂ© de poursuivre la vaccination n'est mentionnĂ© au mĂ©decin traitant que dans 15% des cas, et dans seulement 11% des cas les modalitĂ©s du calendrier vaccinal sont prĂ©cisĂ©es. La recommandation d'effectuer un contrĂŽle sĂ©rologique n'apparaĂźt dans aucun document de transmission. Chez les mĂ©decins traitants, la 2eme dose de vaccin est administrĂ©e Ă  100% des enfants, mais seulement dans 15% des cas dans les dĂ©lais recommandĂ©s. La 3eme dose de vaccination est administrĂ©e Ă  98% des enfants, mais seulement dans 43% des cas dans les dĂ©lais recommandĂ©s. La sĂ©rologie de contrĂŽle n'est effectuĂ©e que chez 24% des enfants, et seulement dans 7% des cas dans les dĂ©lais recommandĂ©s. Les maternitĂ©s appliquent les mesures de prophylaxie dans le dĂ©lai imparti, tout au moins quand l'heure d'intervention est indiquĂ©e. Les mĂ©decins traitants sont rarement informĂ©s de la nĂ©cessitĂ© de complĂ©ter la vaccination et jamais des modalitĂ©s ni de la nĂ©cessitĂ© d'effectuer un contrĂŽle sĂ©rologique. L'application des mesures de prĂ©vention par les mĂ©decins traitants est non conforme aux recommandations. Nous Ă©mettons l'hypothĂšse que cet Ă©tat reflĂšte la carence d'information de la part des maternitĂ©s et nous proposons que celles-ci utilisent un document de transmission standardisĂ© qui indique prĂ©cisĂ©ment aux mĂ©decins traitants ce qui reste Ă  faire, et quand, en matiĂšre de prĂ©vention de l'hĂ©patite B chez le nouveau-nĂ©/nourrisson
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