João Carlos Pinheiro

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The analysis of data from dose-response studies has long been divided according to two major strategies: multiple comparison procedures and model-based approaches. Model-based approaches assume a functional relationship between the response and the dose, taken as a quantitative factor, according to a prespecified parametric model. The fitted model is then(More)
In this paper, the authors present a three-level mediator based framework for linked data integration. In the approach, the mediated schema is represented by a domain ontology, which provides a conceptual representation of the application. Each relevant data source is described by a source ontology, published on the Web according to the Linked Data(More)
In this paper, we present a three-level ontology-based framework for effectively designing GAV data integration systems. In our approach, the mediated schema is represented by a domain ontology, which provides a conceptual representation of the application. Each local source is described by an application ontology, whose vocabulary is restricted to be a(More)
Clinical trials generally include several outcome measures of interest for assessing treatment efficacy and harm. Traditionally a single measure, the primary outcome, is selected and used as the basis for the design, including sample size and power. Secondary outcomes are then generally ordered with respect to their clinical relevance and importance. While(More)
OBJECTIVES Combination of multiple testing and modeling techniques in dose-response studies. Use of hypotheses tests to assess the significance of the dose-response signal associated with a given candidate dose-response model. Estimation of target dose(s) following the previous model selection step. Illustration of the method with a real data example. (More)
1 The Proposed Framework Ontologies have been extensively used to model domain-specific knowledge. The main reason for this success is due to their capability to be at the " semantic " level, away from data structures and implementation strategies. In addition, ontology formalisms have allowed certain kinds of reasoning to be automated within a reasonable(More)
Motivated by the success of Linked Data and driven by the growing number of data sources into RDF files available on the web, new challenges for query processing are emerging, especially in distributed settings. These environments allow distributed execution of federated queries, which involve joining data provided by multiple sources, which are often(More)
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