98 resultados para Decision-processes


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Drug delivery is one of the most common clinical routines in hospitals, and is critical to patients' health and recovery. It includes a decision making process in which a medical doctor decides the amount (dose) and frequency (dose interval) on the basis of a set of available patients' feature data and the doctor's clinical experience (a priori adaptation). This process can be computerized in order to make the prescription procedure in a fast, objective, inexpensive, non-invasive and accurate way. This paper proposes a Drug Administration Decision Support System (DADSS) to help clinicians/patients with the initial dose computing. The system is based on a Support Vector Machine (SVM) algorithm for estimation of the potential drug concentration in the blood of a patient, from which a best combination of dose and dose interval is selected at the level of a DSS. The addition of the RANdom SAmple Consensus (RANSAC) technique enhances the prediction accuracy by selecting inliers for SVM modeling. Experiments are performed for the drug imatinib case study which shows more than 40% improvement in the prediction accuracy compared with previous works. An important extension to the patient features' data is also proposed in this paper.

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So-called online Voting Advice Applications (VAAs) have become very popular all over Europe. Millions of voters are using them as an assistance to make up their minds for which party they should vote. Despite this popularity there are only very few studies about the impact of these tools on individual electoral choice. On the basis of the Swiss VAA smartvote we present some first findings about the question whether VAAs do have a direct impact on the actual vote of their users. In deed, we find strong evidence that Swiss voters were affected by smartvote. However, our findings are somewhat contrary to the results of previous studies from other countries. Furthermore, the quality of available data for such studies needs to be improved. Future studies should pay attention to both: the improvement of the available data, as well as the explanation of the large variance of findings between the specific European countries.

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The legitimacy of the WTO's decision-making process has always been questioned, and many have advocated public participation mechanisms as a remedy. The present study considers the limits and potential of these mechanisms by advancing a conceptual framework, which distinguishes the four 'implementation parameters' of public participation: the goal, the object, the modalities, and the actors. It addresses the issue of legitimacy by considering to what extent, and by virtue of which legal developments, one can see implementing the democratic principle as a goal for public participation in the context of the WTO. By analyzing the institutional structure of the WTO and its different types of decisions, it then outlines how this goal should influence the object and modalities of public participation, which decision-making procedures should be opened to public participation, and how the mechanisms should be implemented in practice. Finally, it suggests speciflrc amendments to existing WTO affangements on public participation

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La problématique centrale de cette thèse de doctorat est l'efficacité de l'accompagnement à l'orientation. Elle renvoie en particulier à la multiplicité des types d'interventions ainsi qu'aux tensions entre les finalités de l'orientation qui rendent improbable une mesure univoque et objective de l'efficacité des pratiques. Le «mythe » de l'efficacité trouve notamment sa source dans le persistent monopole du modèle de l'appariement qui a largement influencé le développement de la discipline. Le manuscrit est basé sur deux études empiriques. Premièrement, « voies professionnelles » est une étude longitudinale visant l'évaluation de l'efficacité d'un service de counseling d'orientation au travers de mesures intraindividuelles. Les résultats immédiats (pre-post) indiquent une forte diminution de l'indécision vocationnelle des consultants ainsi qu'une augmentation de leur bien-être. Les résultats longitudinaux sur un an indiquent une évolution positive des difficultés plus ancrées ainsi qu'un fort taux d'implémentation des projets professionnels. La qualité de l'alliance de travail démontre un impact positif sur l'efficacité de la démarche. Deuxièmement, l'étude « orientation et genre » a permis de mettre en évidence un effet d'interaction entre le sexe et le niveau scolaire d'élèves en fin de scolarité sur leurs profils d'intérêts professionnels. Ce résultat affecte en particulier les jeunes filles dans une filière à exigences élémentaires car ces deux identités psychosociales semblent restreindre doublement les options professionnelles envisageables. Les deux études ont permis de soulever cinq implications centrales : (1) La distinction entre les aspects cognitifs et émotionnels de l'indécision vocationnelle est importante. En particulier, la préparation au choix est un construit qui nécessite clarification ; (2) Les processus de transitions professionnelles ainsi que leur accompagnement doivent être considérés dans leur dimension temporelle ; (3) L'interconnexion des différentes sphères de vie est centrale dans les processus d'orientation et leur accompagnement ; (4) L'efficacité du conseil en orientation est affectée par la qualité des aspects relationnels ; (5) La complexité des pratiques et de leurs finalités confronte l'orientation à son rôle envers des identités psychosociales fragilisées. - The central issue of this doctoral thesis is the effectiveness of career counseling and guidance. In particular, this refers to the many types of career interventions as well as the tensions between their objectives. Those aspects make it unlikely to get an unambiguous and objective measure of the effectiveness of career practices. The "myth of efficiency" is particularly rooted in the persistent monopoly of person-environment fit models, which greatly influenced the development of the discipline. This manuscript is based on two empirical studies. First, "career paths" is a longitudinal study looking at the effectiveness of a career counseling service through intraindividual measures. Pre-post impacts showed a significant decrease in clients' vocational indecision as well as a moderate increase in their well-being. The one year-longitudinal results highlighted significant decreases in more constant decision-making difficulties with a high proportion of clients having implemented their professional projects. The quality of the working alliance had a positive impact on the effectiveness of the intervention. The second study, "vocational development and gender" highlighted an interaction effect between late schoolchildren's gender and school level on their professional interests profile. This result particularly affected girls at a low school level, because these psychosocial identities were a double restraint in restricting career options. The two studies raised five central implications: (1) The distinction between cognitive and emotional aspects of vocational indecision is important. In particular, readiness to make a choice is a construct that requires clarification; (2) career transitions processes as well as supporting these transitions, should be considered in their temporal dimension (3) the interconnection of different spheres of life is central to vocational development and career guidance and counseling; (4) the effectiveness of career counseling is affected by the quality of the relational aspects in the intervention; (5) and the complexity of career interventions and their objectives forces practitioners to consider their role and responsibilities towards clients with marginalized psychosocial identities.

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Considering genetic relatedness among species has long been argued as an important step toward measuring biological diversity more accurately, rather than relying solely on species richness. Some researchers have correlated measures of phylogenetic diversity and species richness across a series of sites and suggest that values of phylogenetic diversity do not differ enough from those of species richness to justify their inclusion in conservation planning. We compared predictions of species richness and 10 measures of phylogenetic diversity by creating distribution models for 168 individual species of a species-rich plant family, the Cape Proteaceae. When we used average amounts of land set aside for conservation to compare areas selected on the basis of species richness with areas selected on the basis of phylogenetic diversity, correlations between species richness and different measures of phylogenetic diversity varied considerably. Correlations between species richness and measures that were based on the length of phylogenetic tree branches and tree shape were weaker than those that were based on tree shape alone. Elevation explained up to 31% of the segregation of species rich versus phylogenetically rich areas. Given these results, the increased availability of molecular data, and the known ecological effect of phylogenetically rich communities, consideration of phylogenetic diversity in conservation decision making may be feasible and informative.

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The significance of the Brianconnais domain in the Alpine orogen is reviewed in the light of data concerning its collision with the active Adriatic margin and the passive Helvetic margin. The Brianconnais which formerly belonged to the Iberian plate, was located on the northern margin of the Alpine Tethys (Liguro-Piemont ocean) since its opening in the early-Middle Jurassic. Together with the Iberian plate the Brianconnais terrane was separated from the European plate in the Late Jurassic-Early Cretaceous, following the northern Atlantic, Bay of Biscay, Valais ocean opening. This was accompanied by the onset of subduction along the northern margin of Adria and the closure of the Alpine Tethys. Stratigraphic and metamorphic data regarding this subduction and the geohistory of the Brianconnais allows the scenario of subduction-obduction processes during the Late Cretaceous-early Tertiary in the eastern and western Alps to be specified. HP-LT metamorphism record a long-lasting history of oceanic subduction-accretion, followed in the Middle Eocene by the incorporation of the Brianconnais as an exotic terrane into the accretionary prism. Middle to Late Eocene cooling ages of the Brianconnais basement and the presence of pelagic, anorogenic sedimentation lasting until the Middle Eocene on the Brianconnais preclude any sort of collision before that time between this domain and the active Adria margin or the Helvetic margin. This is confirmed by plate reconstructions constrained by magnetic anomalies in the Atlantic domain. Only a small percentage of the former Brianconnais domain was obducted, most of the crust and lithospheric roots were subducted. This applies also to domains formerly belonging to the southern Alpine Tethys margin (Austroalpine-inner Carpathian domain). It is proposed that there was a single Palaeogene subduction zone responsible for the Alpine orogen formation (from northern Spain to the East Carpathians), with the exception of a short-lived Late Cretaceous partial closure of the Valais ocean. Subduction in the western Tethyan domain originated during the closure of the Meliata ocean during the Jurassic incorporating the Austroalpine-Carpathian domain as terranes during the Cretaceous. The subduction zone propagated into the northern margin of Adria and then to the northern margin of the Iberian plate, where it gave birth to the Pyrenean-Provencal orogenic belt. This implies the absence of a separated Cretaceous subduction zone within the Austro-Carpathian Penninic ocean. Collision of Iberia with Europe forced the subduction to jump to the SE margin of Iberia in the Eocene, creating the Apenninic orogenic wedge and inverting the vergence of subduction from south- to north-directed. (C) 1998 Elsevier Science B.V. All rights reserved.

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Sampling issues represent a topic of ongoing interest to the forensic science community essentially because of their crucial role in laboratory planning and working protocols. For this purpose, forensic literature described thorough (Bayesian) probabilistic sampling approaches. These are now widely implemented in practice. They allow, for instance, to obtain probability statements that parameters of interest (e.g., the proportion of a seizure of items that present particular features, such as an illegal substance) satisfy particular criteria (e.g., a threshold or an otherwise limiting value). Currently, there are many approaches that allow one to derive probability statements relating to a population proportion, but questions on how a forensic decision maker - typically a client of a forensic examination or a scientist acting on behalf of a client - ought actually to decide about a proportion or a sample size, remained largely unexplored to date. The research presented here intends to address methodology from decision theory that may help to cope usefully with the wide range of sampling issues typically encountered in forensic science applications. The procedures explored in this paper enable scientists to address a variety of concepts such as the (net) value of sample information, the (expected) value of sample information or the (expected) decision loss. All of these aspects directly relate to questions that are regularly encountered in casework. Besides probability theory and Bayesian inference, the proposed approach requires some additional elements from decision theory that may increase the efforts needed for practical implementation. In view of this challenge, the present paper will emphasise the merits of graphical modelling concepts, such as decision trees and Bayesian decision networks. These can support forensic scientists in applying the methodology in practice. How this may be achieved is illustrated with several examples. The graphical devices invoked here also serve the purpose of supporting the discussion of the similarities, differences and complementary aspects of existing Bayesian probabilistic sampling criteria and the decision-theoretic approach proposed throughout this paper.

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Objective: The relationship between physicians and patients has undergone¦important changes, and the current emancipation of patients has led to¦a real partnership in medical decision-making. This study aimed to assess¦patients' preferences on different aspects of decision-making during treatment¦and potential complications, as well as the amount and type of preoperative¦information before visceral surgery.¦Methods: Prospective non-randomized study based on a questionnaire given¦to 253 consecutive patients scheduled for elective GI surgery.¦Results: Concerning surgical complications or treatment in the intensive care¦unit, 64% of patients wished to take actively part in any medical decisions.¦The respective figures for cardiac resuscitation and treatment limitations were¦89% and 60%. About information, 73%, 77% and 47% of patients wish¦detailed information, information on a potential ICUhospitalization and cardiac¦resuscitation, respectively. Elderly and low-educated patients were significantly¦less interested in shared medical decision-making (p = 0·003 and 0·015) and in¦information receiving (p = 0·03 and 0·05). Similarly, involvement of the family¦in decision-making was significantly less important in elderly and male patients¦(p = 0·05 and 0·03 respectively). Neither the type of operation (minor or major)¦nor the severity of disease (malignancies vs. non-malignancies) was a significant¦factor for shared decision-making, information or family involvement.¦Conclusion: The vast majority of surgical patients clearly want to get adequate¦preoperative information about their disease and the planned treatment. They¦also consider it as crucial to be involved in any kind of decision-making for¦treatment and complications. The family's role is limited to support the treating¦physicians if the patient is unable to participate in taking decisions.

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The capacity to learn to associate sensory perceptions with appropriate motor actions underlies the success of many animal species, from insects to humans. The evolutionary significance of learning has long been a subject of interest for evolutionary biologists who emphasize the bene¬fit yielded by learning under changing environmental conditions, where it is required to flexibly switch from one behavior to another. However, two unsolved questions are particularly impor¬tant for improving our knowledge of the evolutionary advantages provided by learning, and are addressed in the present work. First, because it is possible to learn the wrong behavior when a task is too complex, the learning rules and their underlying psychological characteristics that generate truly adaptive behavior must be identified with greater precision, and must be linked to the specific ecological problems faced by each species. A framework for predicting behavior from the definition of a learning rule is developed here. Learning rules capture cognitive features such as the tendency to explore, or the ability to infer rewards associated to unchosen actions. It is shown that these features interact in a non-intuitive way to generate adaptive behavior in social interactions where individuals affect each other's fitness. Such behavioral predictions are used in an evolutionary model to demonstrate that, surprisingly, simple trial-and-error learn¬ing is not always outcompeted by more computationally demanding inference-based learning, when population members interact in pairwise social interactions. A second question in the evolution of learning is its link with and relative advantage compared to other simpler forms of phenotypic plasticity. After providing a conceptual clarification on the distinction between genetically determined vs. learned responses to environmental stimuli, a new factor in the evo¬lution of learning is proposed: environmental complexity. A simple mathematical model shows that a measure of environmental complexity, the number of possible stimuli in one's environ¬ment, is critical for the evolution of learning. In conclusion, this work opens roads for modeling interactions between evolving species and their environment in order to predict how natural se¬lection shapes animals' cognitive abilities. - La capacité d'apprendre à associer des sensations perceptives à des actions motrices appropriées est sous-jacente au succès évolutif de nombreuses espèces, depuis les insectes jusqu'aux êtres hu¬mains. L'importance évolutive de l'apprentissage est depuis longtemps un sujet d'intérêt pour les biologistes de l'évolution, et ces derniers mettent l'accent sur le bénéfice de l'apprentissage lorsque les conditions environnementales sont changeantes, car dans ce cas il est nécessaire de passer de manière flexible d'un comportement à l'autre. Cependant, deux questions non résolues sont importantes afin d'améliorer notre savoir quant aux avantages évolutifs procurés par l'apprentissage. Premièrement, puisqu'il est possible d'apprendre un comportement incorrect quand une tâche est trop complexe, les règles d'apprentissage qui permettent d'atteindre un com¬portement réellement adaptatif doivent être identifiées avec une plus grande précision, et doivent être mises en relation avec les problèmes écologiques spécifiques rencontrés par chaque espèce. Un cadre théorique ayant pour but de prédire le comportement à partir de la définition d'une règle d'apprentissage est développé ici. Il est démontré que les caractéristiques cognitives, telles que la tendance à explorer ou la capacité d'inférer les récompenses liées à des actions non ex¬périmentées, interagissent de manière non-intuitive dans les interactions sociales pour produire des comportements adaptatifs. Ces prédictions comportementales sont utilisées dans un modèle évolutif afin de démontrer que, de manière surprenante, l'apprentissage simple par essai-et-erreur n'est pas toujours battu par l'apprentissage basé sur l'inférence qui est pourtant plus exigeant en puissance de calcul, lorsque les membres d'une population interagissent socialement par pair. Une deuxième question quant à l'évolution de l'apprentissage concerne son lien et son avantage relatif vis-à-vis d'autres formes plus simples de plasticité phénotypique. Après avoir clarifié la distinction entre réponses aux stimuli génétiquement déterminées ou apprises, un nouveau fac¬teur favorisant l'évolution de l'apprentissage est proposé : la complexité environnementale. Un modèle mathématique permet de montrer qu'une mesure de la complexité environnementale - le nombre de stimuli rencontrés dans l'environnement - a un rôle fondamental pour l'évolution de l'apprentissage. En conclusion, ce travail ouvre de nombreuses perspectives quant à la mo¬délisation des interactions entre les espèces en évolution et leur environnement, dans le but de comprendre comment la sélection naturelle façonne les capacités cognitives des animaux.