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Gu, X., Sidén, P., Wegmann, B., Eklund, A., Villani, M. & Knutsson, H. (2017). Bayesian Diffusion Tensor Estimation with Spatial Priors. In: CAIP 2017: Computer Analysis of Images and Patterns. Paper presented at International Conference on Computer Analysis of Images and Patterns (pp. 372-383). , 10424
Öppna denna publikation i ny flik eller fönster >>Bayesian Diffusion Tensor Estimation with Spatial Priors
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2017 (Engelska)Ingår i: CAIP 2017: Computer Analysis of Images and Patterns, 2017, Vol. 10424, s. 372-383Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]

Spatial regularization is a technique that exploits the dependence between nearby regions to locally pool data, with the effect of reducing noise and implicitly smoothing the data. Most of the currently proposed methods are focused on minimizing a cost function, during which the regularization parameter must be tuned in order to find the optimal solution. We propose a fast Markov chain Monte Carlo (MCMC) method for diffusion tensor estimation, for both 2D and 3D priors data. The regularization parameter is jointly with the tensor using MCMC. We compare FA (fractional anisotropy) maps for various b-values using three diffusion tensor estimation methods: least-squares and MCMC with and without spatial priors. Coefficient of variation (CV) is calculated to measure the uncertainty of the FA maps calculated from the MCMC samples, and our results show that the MCMC algorithm with spatial priors provides a denoising effect and reduces the uncertainty of the MCMC samples.

Serie
Lecture Notes in Computer Science, ISSN 0302-9743, E-ISSN 1611-3349 ; 10424
Nyckelord
Spatial regularization, Diffusion tensor, Spatial priors Markov chain, Monte Carlo Fractional anisotropy
Nationell ämneskategori
Medicinteknik
Identifikatorer
urn:nbn:se:liu:diva-139844 (URN)10.1007/978-3-319-64689-3_30 (DOI)000432085900030 ()978-3-319-64689-3 (ISBN)978-3-319-64688-6 (ISBN)
Konferens
International Conference on Computer Analysis of Images and Patterns
Anmärkning

Funding agencies: Information Technology for European Advancement (ITEA) 3 Project BENEFIT (better effectiveness and efficiency by measuring and modelling of interventional therapy); Swedish Research Council [2015-05356, 2013-5229]; National Institute of Dental and Craniof

Tillgänglig från: 2017-08-17 Skapad: 2017-08-17 Senast uppdaterad: 2018-06-01
Wegmann, B. (2015). Bayesian comparison of private and common values in structural second-price auctions. Journal of Applied Statistics, 42(2), 380-397
Öppna denna publikation i ny flik eller fönster >>Bayesian comparison of private and common values in structural second-price auctions
2015 (Engelska)Ingår i: Journal of Applied Statistics, ISSN 0266-4763, E-ISSN 1360-0532, Vol. 42, nr 2, s. 380-397Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Private and common values (CVs) are the two main competing valuation models in auction theory and empirical work. In the framework of second-price auctions, we compare the empirical performance of the independent private value (IPV) model to the CV model on a number of different dimensions, both on real data from eBay coin auctions and on simulated data. Both models fit the eBay data well with a slight edge for the CV model. However, the differences between the fit of the models seem to depend to some extent on the complexity of the models. According to log predictive score the IPV model predicts auction prices slightly better in most auctions, while the more robust CV model is much better at predicting auction prices in more unusual auctions. In terms of posterior odds, the CV model is clearly more supported by the eBay data.

Ort, förlag, år, upplaga, sidor
Taylor and Francis (Routledge): STM, Behavioural Science and Public Health Titles, 2015
Nyckelord
Markov chain Monte Carlo; private values; eBay; Bayesian variable selection; common values; Gaussian model
Nationell ämneskategori
Matematik
Identifikatorer
urn:nbn:se:liu:diva-112602 (URN)10.1080/02664763.2014.951604 (DOI)000344560700011 ()
Anmärkning

Funding Agencies|Jan Wallander and Tom Hedelius Foundation

Tillgänglig från: 2014-12-10 Skapad: 2014-12-05 Senast uppdaterad: 2017-12-05
Organisationer
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0003-2193-6003

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