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VRAC: Theory #1 [article]

Aubin Jarry, Pierre Leone, Jose Rolim
2010 arXiv   pre-print
∈{1,..  ...  • 1 0 1 || ∂c ∂(t) ||dt ≤ λd(X 0 , D).  ... 
arXiv:1002.0484v1 fatcat:3iif7tflhvcpxpfjvgaziouoae

Copula analysis of mixture models

M. Vrac, L. Billard, E. Diday, A. Chédin
2011 Computational statistics (Zeitschrift)  
Proofs of (i)-(iii) are found in Diday and Vrac (2005) and of (iv) in Vrac (2002) . The functions in (2) and (4) readily generalize when p > 1.  ...  Vrac (2002) and Diday and Vrac (2005) proposed a triangle method to assist in the choices of Z; Jain and Dubes (1988) also proposed methods to help identify clustering tendencies.  ...  Then there exists a copula C such that for all (x 1 , . . . , x n ) ∈ [0, 1] n , H Z 1 ,...  ... 
doi:10.1007/s00180-011-0266-0 fatcat:4jr2zidywzdmrnkm62ynlnwb2u

Stochastic downscaling of precipitation: From dry events to heavy rainfalls

M. Vrac, P. Naveau
2007 Water Resources Research  
Citation: Vrac, M., and P. Naveau (2007) , Stochastic downscaling of precipitation: From dry events to heavy rainfalls, Water Resour.  ...  1] Downscaling precipitation is a difficult challenge for the climate community. We propose and study a new stochastic weather typing approach to perform such a task.  ...  Past studies [Katz et al., 2002; Naveau et al., 2005] have illustrated how Extreme Value Theory (EVT), a statistical theory developed over the past 80 years, provides the mathematical foundation for  ... 
doi:10.1029/2006wr005308 fatcat:moycz2ansfbetamrvxiou7dpnu

Modeling pairwise dependencies in precipitation intensities

M. Vrac, P. Naveau, P. Drobinski
2007 Nonlinear Processes in Geophysics  
These definitions allow the hydrologist and the flood planner to apply the univariate Extreme Value Theory (EVT) to their time series of interest. But these strategies have two main drawbacks.  ...  rainfall data over the state of Illinois (USA) (Vrac and Naveau, 2007) .  ...  The advantage of this strategy is that an elegant mathematical framework called Extreme Value theory (EVT) developed in 1928 by Fisher and Tippett (1928) and regularly updated during the last decades  ... 
doi:10.5194/npg-14-789-2007 fatcat:4ppxr7jqgngpfovedye7vympuq

Multivariate stochastic bias corrections with optimal transport

Yoann Robin, Mathieu Vrac, Philippe Naveau, Pascal Yiou
2019 Hydrology and Earth System Sciences  
The optimal transport theory allows us to construct a joint distribution that minimizes an energy spent in bias correction.  ...  ., Vrac and Friederichs, 2015; Vrac, 2018; Nahar et al., 2018; Cannon, 2018) .  ...  As mentioned by Vrac (2018) , two kinds of methods are currently available.  ... 
doi:10.5194/hess-23-773-2019 fatcat:ilpz3z6lebgqlcztccpqrv4z7y

Statistical downscaling of river flows

Clement Tisseuil, Mathieu Vrac, Sovan Lek, Andrew J. Wade
2010 Journal of Hydrology  
Moreover, the downscaling of daily anomalies could also take advantage of the extreme value theory (Coles, 2001; Katz et al., 2002; Vrac and Naveau, 2007) to improve high percentiles simulations.  ...  1 Abbreviations.  ... 
doi:10.1016/j.jhydrol.2010.02.030 fatcat:rhx4u6slcjaazfsnwsasv2h6wq

Nonstationary probabilistic downscaling of extreme precipitation

M. Kallache, M. Vrac, P. Naveau, P.-A. Michelangeli
2011 Journal of Geophysical Research  
1] Reanalysis data and general circulation model outputs typically provide information at a coarse spatial resolution, which cannot directly be used for local impact studies.  ...  We primarily used the R package CDFt from Mathieu Vrac and Paul-Antoine Michelangeli.  ...  ., Wilks and Wilby, 1999; Vrac and Naveau, 2007] . Until recently, most studies have been based on the downscaling of mean values [Fowler et al., 2007] .  ... 
doi:10.1029/2010jd014892 fatcat:nejwkdqpbncsrfpnmbpirkpz5q

Statistical downscaling of precipitation through nonhomogeneous stochastic weather typing

M Vrac, M Stein, K Hayhoe
2007 Climate Research (CR)  
Regional climate conditions are categorized in terms of 2 different types of weather states: (1) 'precipitation patterns' developed by a hierarchical ascending clustering (HAC) method with an original  ...  developed a statistical mixture of 'distributions of distributions' through the copulas theory to determine air mass types from vertical atmospheric profiles of specific humidity and temperature (Naveau  ...  Recently, Vrac et al. (2007) showed that the statistical mixture clustering method tends to produce more consistent results than a hierarchical clustering approach across various datasets (e.g.  ... 
doi:10.3354/cr00696 fatcat:gm4f2ucopvfnplnrmigxflq524

Restructuring of genomic provinces of surface ocean plankton under climate change [article]

Paul Frémont, Marion Gehlen, Mathieu Vrac, Jade Leconte, Patrick Wincker, Daniele Iudicone, Olivier Jaillon
2020 bioRxiv   pre-print
Here, niche theory is applied on plankton metagenomes sampled during the Tara Oceans expedition to derive pan-ocean geographical structuring in climatic provinces for 6 size fractions, from viruses to  ...  Fig. 1 | 1 Fig. 1 | Signature genomes of provinces of eukaryotes enriched size classes.  ...  We find an average displacement speed of the provinces' centroids of 76 ± 79 km.dec -1 (latitudinally mean of 34 ± 82 km.dec -1 and 59 ± 82 km.dec -1 longitudinally; median of 47 km.dec -1 , 23 km.dec  ... 
doi:10.1101/2020.10.20.347237 fatcat:enuscfgyfbbrbp2qz6v6oteezu

Conditional simulations of the extremal t process: Application to fields of extreme precipitation

Aurélien Bechler, Liliane Bel, Mathieu Vrac
2015 Spatial Statistics  
Ducrocq et al. (2008) ; Lebeaupin et al. (2006) ; Beaulant et al. (2011) ; Vrac and Yiou (2010) or Vrac et al. (2012) ).  ...  The extreme value theory is well established for univariate stationary series.  ... 
doi:10.1016/j.spasta.2015.04.003 fatcat:6hcziha4m5hh7fmdn5rmpbwvqa

Adjusting spatial dependence of climate model outputs with cycle-consistent adversarial networks

Bastien François, Soulivanh Thao, Mathieu Vrac
2021 Climate Dynamics  
In theory, this choice of conditioning dimensions allows R 2 D 2 to partially recover temporal properties of the reference dataset (Vrac and Thao 2020) .  ...  ., Vrac 2018) .  ...  the 1d-BC named CDFt (Vrac et al. 2012) .  ... 
doi:10.1007/s00382-021-05869-8 fatcat:w62fhb2zpzcpnakyqpkztonoba

Cell Death Induction and Protection by Activation of Ubiquitously Expressed Anion/Cation Channels. Part 1: Roles of VSOR/VRAC in Cell Volume Regulation, Release of Double-Edged Signals and Apoptotic/Necrotic Cell Death

Yasunobu Okada, Ravshan Z. Sabirov, Kaori Sato-Numata, Tomohiro Numata
2021 Frontiers in Cell and Developmental Biology  
The Part 1 focuses on the roles of the volume-sensitive outwardly rectifying anion channels (VSOR), also called the volume-regulated anion channel (VRAC), which is activated by cell swelling or reactive  ...  First we describe phenotypical properties, the molecular identity, and physical pore dimensions of VSOR/VRAC.  ...  and glutamate (R ∼ 0.35 nm) very freely, and also ATP, ADP and UTP FIGURE 1 | VSOR/VRAC pore size and dimensions of the signaling molecules released via VSOR/VRAC.  ... 
doi:10.3389/fcell.2020.614040 pmid:33511120 pmcid:PMC7835517 fatcat:5ijnzt3t5rf75hbhmudvxdtfzu

A spatial hybrid approach for downscaling of extreme precipitation fields

Aurélien Bechler, Mathieu Vrac, Liliane Bel
2015 Journal of Geophysical Research - Atmospheres  
., 2010; Vrac et al., 2012] .  ...  and Yiou, 2010; Vrac et al., 2012] .  ...  For models better than the reference model, S skill belongs to [0, 1] and 1 corresponds to the optimal case.  ... 
doi:10.1002/2014jd022558 fatcat:zaxklhjjmvaxdfpjpcy5kvmhsa

Statistical issues about solar–climate relations

P. Yiou, E. Bard, P. Dandin, B. Legras, P. Naveau, H. W. Rust, L. Terray, M. Vrac
2010 Climate of the Past  
L (t) = Q (t)/ζ (t). (6) This denomination is not connected with the lifetime notion in statistical survival theory (e.g. Lawless, 2003) .  ...  : C X (τ ) = 1 N − τ N −τ t=1 X(t + τ )X(t).  ... 
doi:10.5194/cp-6-565-2010 fatcat:tkxia54s6rcdhchw57jx6cg3hm

Statistical issues about solar-climate relations

P. Yiou, E. Bard, P. Dandin, B. Legras, P. Naveau, H. W. Rust, L. Terray, M. Vrac
2010 Climate of the Past Discussions  
L (t) = Q (t)/ζ (t). (6) This denomination is not connected with the lifetime notion in statistical survival theory (e.g. Lawless, 2003) .  ...  : C X (τ ) = 1 N − τ N −τ t=1 X(t + τ )X(t).  ... 
doi:10.5194/cpd-6-461-2010 fatcat:x2wewi4fovcarayxhz3mkezbee
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