847 research outputs found
Optimal Two-Step Prediction in Regression
High-dimensional prediction typically comprises two steps: variable selection
and subsequent least-squares refitting on the selected variables. However, the
standard variable selection procedures, such as the lasso, hinge on tuning
parameters that need to be calibrated. Cross-validation, the most popular
calibration scheme, is computationally costly and lacks finite sample
guarantees. In this paper, we introduce an alternative scheme, easy to
implement and both computationally and theoretically efficient
Continuous cutting plane algorithms in integer programming
Cutting planes for mixed-integer linear programs (MILPs) are typically
computed in rounds by iteratively solving optimization problems. Instead, we
reframe the problem of finding good cutting planes as a continuous optimization
problem over weights parametrizing families of valid inequalities. We propose a
practical two-step algorithm, and demonstrate empirical gains when optimizing
Gomory mixed-integer inequalities over various families of MILPs. Finally, a
reinterpretation of our approach as optimization of the subadditive dual using
a deep neural network is provided. Code for reproducing the experiments can be
found at https://github.com/dchetelat/subadditive
Why musical memory can be preserved in advanced Alzheimer's disease
Musical memory is relatively preserved in Alzheimer's disease and other dementias. In a 7 Tesla functional MRI study employing multi-voxel pattern analysis, Jacobsen et al. identify brain regions encoding long-term musical memory in young healthy controls, and show that these same regions display relatively little atrophy and hypometabolism in patients with Alzheimer's disease.See Clark and Warren (doi:10.1093/brain/awv148) for a scientific commentary on this article.
Musical memory is relatively preserved in Alzheimer's disease and other dementias. In a 7 Tesla functional MRI study employing multi-voxel pattern analysis, Jacobsen et al. identify brain regions encoding long-term musical memory in young healthy controls, and show that these same regions display relatively little atrophy and hypometabolism in patients with Alzheimer's disease.See Clark and Warren (doi:10.1093/awv148) for a scientific commentary on this article
La prévalence et les facteurs de risque de la maladie d’Osgood-Schlatter, revue de la littérature et méta-analyse
La maladie d’Osgood-Schlatter est l’ostéochondrose de croissance la plus fréquente. Elle touche les enfants et adolescents entre 7 et 21 ans. Cette revue vise à définir la prévalence dans différentes populations et à identifier les facteurs de risque importants de cette pathologie
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