Search results for "Statistic"
showing 10 items of 12520 documents
Coupled conditional backward sampling particle filter
2020
The conditional particle filter (CPF) is a promising algorithm for general hidden Markov model smoothing. Empirical evidence suggests that the variant of CPF with backward sampling (CBPF) performs well even with long time series. Previous theoretical results have not been able to demonstrate the improvement brought by backward sampling, whereas we provide rates showing that CBPF can remain effective with a fixed number of particles independent of the time horizon. Our result is based on analysis of a new coupling of two CBPFs, the coupled conditional backward sampling particle filter (CCBPF). We show that CCBPF has good stability properties in the sense that with fixed number of particles, …
Uncertainty quantification on a spatial Markov-chain model for the progression of skin cancer
2019
AbstractA spatial Markov-chain model is formulated for the progression of skin cancer. The model is based on the division of the computational domain into nodal points, that can be in a binary state: either in ‘cancer state’ or in ‘non-cancer state’. The model assigns probabilities for the non-reversible transition from ‘non-cancer’ state to the ‘cancer state’ that depend on the states of the neighbouring nodes. The likelihood of transition further depends on the life burden intensity of the UV-rays that the skin is exposed to. The probabilistic nature of the process and the uncertainty in the input data is assessed by the use of Monte Carlo simulations. A good fit between experiments on mi…
From Feynman–Kac formulae to numerical stochastic homogenization in electrical impedance tomography
2016
In this paper, we use the theory of symmetric Dirichlet forms to derive Feynman–Kac formulae for the forward problem of electrical impedance tomography with possibly anisotropic, merely measurable conductivities corresponding to different electrode models on bounded Lipschitz domains. Subsequently, we employ these Feynman–Kac formulae to rigorously justify stochastic homogenization in the case of a stochastic boundary value problem arising from an inverse anomaly detection problem. Motivated by this theoretical result, we prove an estimate for the speed of convergence of the projected mean-square displacement of the underlying process which may serve as the theoretical foundation for the de…
"Table 31" of "Search for photonic signatures of gauge-mediated supersymmetry in 8 TeV $pp$ collisions with the ATLAS detector"
2015
The total NLO cross sections with uncertainties for the electroweak production GGM signal grid for the photon+j analysis.
"Table 7" of "Measurement of the differential cross-section of highly boosted top quarks as a function of their transverse momentum in $\sqrt{s}$ = 8…
2016
Correlation matrix between the bins of the particle-level differential cross-section as a function of $p_{T,ptcl}$.
Combined Innovation Policy: Linking Scientific and Practical Knowledge in Innovation Systems
2012
New research indicates that firms combining the science-based STI (Science, Technology, Innovation) and the experience-based DUI (Doing, Using, Interacting) modes of innovation are more efficient when it comes to improving innovation capacity and competitiveness. With regard to innovation policy, the STI mode calls for a supply driven policy, typically aimed to commercialise research results. The DUI mode suggests a demand driven policy approach, such as supporting the development of new products or services to specific markets. This paper analyses how the two types of innovation policy and the two innovation modes can be combined in regional innovation systems. The analysis builds on studi…
STABILITY OF A STOCHASTICALLY PERTURBED MODEL OF INTRACELLULAR SINGLE-STRANDED RNA VIRUS REPLICATION
2019
Compared to the replication of double-stranded RNA and DNA viruses, the replication of single-stranded viruses requires the production of a number of intermediate strands that serve as templates for the synthesis of genomic-sense strands. Two theoretical extreme mechanisms for replication for such single-stranded viruses have been proposed; one extreme being represented by the so-called linear stamping machine and the opposite extreme by the exponential growth. Of course, real systems are more complex and examples have been described in which a combination of such extreme mechanisms can also occur: a fraction of the produced progeny resulting from a stamping-machine type of replication that…
Description of hard-sphere crystals and crystal-fluid interfaces: a comparison between density functional approaches and a phase-field crystal model.
2012
In materials science the phase field crystal approach has become popular to model crystallization processes. Phase field crystal models are in essence Landau-Ginzburg-type models, which should be derivable from the underlying microscopic description of the system in question. We present a study on classical density functional theory in three stages of approximation leading to a specific phase field crystal model, and we discuss the limits of applicability of the models that result from these approximations. As a test system we have chosen the three--dimensional suspension of monodisperse hard spheres. The levels of density functional theory that we discuss are fundamental measure theory, a …
The WHO-5 Well-Being Index – Validation based on item response theory and the analysis of measurement invariance across 35 countries.
2020
Abstract Background The five-item World Health Organization Well-Being Index (WHO-5) is a frequently used brief standard measure in large-scale cross-cultural clinical studies. Despite its frequent use, some psychometric questions remain that concern the choice of an adequate item response theory (IRT) model, the evaluation of reliability at important cutoff points, and most importantly the assessment of measurement invariance across countries. Methods Data from the 6th European Working Condition survey (2015) were used that collected nationally representative samples of employed and self-employed individuals (N = 43,469) via computer-aided personal interviews across 35 European countries. …
Field rules and bias in random surveys with quota samples : an assessment of CIS surveys
2018
Surveys applying quota sampling in their final step are widely used in opinion and market research all over the world. This is also the case in Spain, where the surveys carried out by CIS (a public institution for sociological research supported by the government) have become a point of reference. The rules used by CIS to select individuals within quotas, however, could be improved as they lead to biases in age distributions. Analysing more than 545,000 responses collected in the 220 monthly barometers conducted between 1997 and 2016 by CIS, we compare the empirical distributions of the barometers with the expected distributions from the sample design and/or target populations. Among other …