Blar i tittel Artikler, rapporter og annet (matematikk og statistikk)

Viser treff 307-314 av 314

    • Vaccination criteria based on factors influencing COVID-19 diffusion and mortality 

      Spassiani, Ilaria; Gubian, Lorenzo; Palu, Giorgio; Sebastiani, Giovanni (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-12-15)
      SARS-CoV-2 is highly contagious, rapidly turned into a pandemic, and is causing a relevant number of critical to severe life-threatening COVID-19 patients. However, robust statistical studies of a large cohort of patients, potentially useful to implement a vaccination campaign, are rare. We analyzed public data of about 19,000 patients for the period 28 February to 15 May 2020 by several mathematical ...

    • Validation of prediction models of severe disease course and non-achievement of remission in juvenile idiopathic arthritis part 2: Results of the Nordic model in the Canadian cohort 

      Henrey, Andrew; Rypdal, Veronika Gjertsen; Rypdal, Martin Wibe; Loughin, Thomas; Nordal, Ellen Berit; Guzman, Jaime (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-01-15)
      <b>Background</b> Validated clinical prediction models to identify children with poor prognosis at the time of juvenile idiopathic arthritis (JIA) diagnosis would be very helpful for tailoring treatments, and avoiding under- or over-treatment. Our objective was to externally validate Nordic clinical prediction models in Canadian patients with JIA. <b>Methods</b> We used data from 513 subjects ...

    • Vanishing of the entropy pseudonorm for certain integrable systems 

      Kruglikov, Boris Serafimovich; Matveev, VS (Journal article; Tidsskriftartikkel; Peer reviewed, 2006)

    • Warming trends and long-range dependent climate variability since year 1900: A Bayesian approach 

      Myrvoll-Nilsen, Eirik; Fredriksen, Hege-Beate; Sørbye, Sigrunn Holbek; Rypdal, Martin wibe (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-08-21)
      Temporal persistence in unforced climate variability makes detection of trends in surface temperature difficult. Part of the challenge is methodological since standard techniques assume a separation of time scales between trend and noise. In this work we present a novel Bayesian approach to trend detection under the assumption of long-range dependent natural variability, and we use estimates of ...

    • Wei-type duality theorems for matroids 

      Britz, Thomas; Johnsen, Trygve; Mayhew, Dillon; Shiromoto, Keisuke (Journal article; Tidsskriftartikkel; Peer reviewed, 2012)
      We present several fundamental duality theorems for matroids and more general combinatorial structures. As a special case, these results show that the maximal cardinalities of fixed-ranked sets of a matroid determine the corresponding maximal cardinalities of the dual matroid. Our main results are applied to perfect matroid designs, graphs, transversals, and linear codes over division rings, in each ...

    • Weight spectra of Gabidulin rank-metric codes and Betti numbers 

      Johnsen, Trygve; Pratihar, Rakhi; Verdure, Hugues (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-07-07)
      The Helmholtz equation has been used for modeling the sound pressure field under a harmonic load. Computing harmonic sound pressure fields by means of solving Helmholtz equation can quickly become unfeasible if one wants to study many different geometries for ranges of frequencies. We propose a machine learning approach, namely a feedforward dense neural network, for computing the average sound ...

    • You Just Keep on Pushing My Love over the Borderline: A Rejoinder 

      Simpson, Daniel; Rue, Håvard; Riebler, Andrea Ingeborg; Martins, Thiago Guerrera; Sørbye, Sigrunn Holbek (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-06)
      <i>INTRODUCTION</i>: The point of departure for our paper is that most modern statistical models are built to be flexible enough to model diverse data generating mechanisms. Good statistical practice requires us to limit this flexibility, which is typically controlled by a small number of parameters, to the amount “needed” to model the data at hand. The Bayesian framework provides a natural method ...

    • Younger Dryas ice margin retreat triggered by ocean surface warming in central-eastern Baffin Bay 

      Oksman, Mimmi; Weckström, Kaarina; Miettinen, Arto; Juggins, Stephen; Divine, Dmitry V; Jackson, Rebecca; Telford, Richard; Korsgaard, Niels J.; Kučera, Michal (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-10-18)
      The transition from the last ice age to the present-day interglacial was interrupted by the Younger Dryas (YD) cold period. While many studies exist on this climate event, only few include high-resolution marine records that span the YD. In order to better understand the interactions between ocean, atmosphere and ice sheet stability during the YD, more high-resolution proxy records from the Arctic, ...