Nicolas Champagnat

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Publications

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An individual-based stochastic model reveals strong constraints on allometric relationships with minimal metabolic and ecological assumptions

Sylvain Billiard , Virgile Brodu , Nicolas Champagnat , Coralie Fritsch

2025

Pré-publication, Document de travail hal-04904545v1
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Quasi-stationary distributions in reducible state spaces

Nicolas Champagnat , Denis Villemonais

2025

Pré-publication, Document de travail hal-03541248v5
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Modelling the effects of biological intervention in a dynamical gene network

Nicolas Champagnat , Rodolphe Loubaton , Laurent Vallat , Pierre Vallois

2025

Pré-publication, Document de travail hal-05058235v1
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On ecological models with sublinear growth

Nicolas Champagnat , Pablo Marquet , Cristóbal Quiñinao , Rolando Rebolledo , Mauricio Tejo et al.

2025

Pré-publication, Document de travail hal-05156816v1
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Semi-Lasso: a weighted Lasso designed for the integration of known regressors in linear model

Nicolas Champagnat , Anne Gégout-Petit , Anouk Rago

2024

Pré-publication, Document de travail hal-04517255v1
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Quasi-compactness criterion for strong Feller kernels with an application to quasi-stationary distributions

Michel Benaïm , Nicolas Champagnat , William Oçafrain , Denis Villemonais

2022

Pré-publication, Document de travail hal-03640205v1
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Quasi-limiting estimates for periodic absorbed Markov chains

Nicolas Champagnat , Denis Villemonais

2022

Pré-publication, Document de travail hal-03823655v1
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Population processes with unbounded extinction rate conditioned to non-extinction

Nicolas Champagnat , Denis Villemonais

2016

Pré-publication, Document de travail hal-01395731v1

Quasi-stationary distribution for multi-dimensional birth and death processes conditioned to survival of all coordinates

Nicolas Champagnat , Denis Villemonais

2015

Pré-publication, Document de travail hal-01188172v1
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An empirical analysis of heavy-tails behavior of financial data: The case for power laws

Nicolas Champagnat , Madalina Deaconu , Antoine Lejay , Nicolas Navet , Souhail Boukherouaa

2013

Pré-publication, Document de travail hal-00851429v1

Uniform Wasserstein convergence of penalized Markov processes

Nicolas Champagnat , Édouard Strickler , Denis Villemonais

Probability Theory and Related Fields, 2025, 192 (3-4), pp.1031-1069. ⟨10.1007/s00440-025-01385-6⟩

Article dans une revue hal-04145204v1
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Degenerate processes killed at the boundary of a domain

Michel Benaïm , Nicolas Champagnat , William Oçafrain , Denis Villemonais

The Annals of Probability, 2025, 53 (2), pp.720-752. ⟨10.1214/24-AOP1720⟩

Article dans une revue hal-03278551v1
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MultiRNAflow: integrated analysis of temporal RNA-seq data with multiple biological conditions

Rodolphe Loubaton , Nicolas Champagnat , Pierre Vallois , Laurent Vallat

Bioinformatics, 2024, 40 (5), pp.4. ⟨10.1093/bioinformatics/btae315⟩

Article dans une revue hal-04407596v1
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Filling the gap between individual-based evolutionary models and Hamilton-Jacobi equations

Nicolas Champagnat , Sylvie Méléard , Sepideh Mirrahimi , Viet Chi Tran

Journal de l'École polytechnique — Mathématiques, 2023, 10, pp.1247-1275. ⟨10.5802/jep.244⟩

Article dans une revue hal-03656608v2
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General criteria for the study of quasi-stationarity

Nicolas Champagnat , Denis Villemonais

Electronic Journal of Probability, In press, ⟨10.1214/22-EJP880⟩

Article dans une revue hal-01672979v3
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Existence, uniqueness and ergodicity for the centered Fleming-Viot process

Nicolas Champagnat , Vincent Hass

Stochastic Processes and their Applications, 2023, 166, pp.104219. ⟨10.1016/j.spa.2023.09.006⟩

Article dans une revue hal-03596777v4
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Transcritical bifurcation for the conditional distribution of a diffusion process

Michel Benaïm , Nicolas Champagnat , William Oçafrain , Denis Villemonais

Journal of Theoretical Probability, 2022, ⟨10.1007/s10959-022-01216-7⟩

Article dans une revue hal-03471911v1
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Convergence of the Fleming-Viot process toward the minimal quasi-stationary distribution

Nicolas Champagnat , Denis Villemonais

ALEA : Latin American Journal of Probability and Mathematical Statistics, 2021, 18, pp.1-15. ⟨10.30757/ALEA.v18-01⟩

Article dans une revue hal-01895618v1
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Probabilistic non-asymptotic analysis of distributed algorithms

Nicolas Champagnat , René Schott , Denis Villemonais

Stochastic Analysis and Applications, 2021, 36 (6), pp.981-998. ⟨10.1080/07362994.2020.1861952⟩

Article dans une revue hal-01710663v2
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Identifying conversion efficiency as a key mechanism underlying food webs evolution : a step forward, or backward ?

Coralie Fritsch , Sylvain Billiard , Nicolas Champagnat

Oikos, 2021, 130 (6), pp.904-930. ⟨10.1111/oik.07421⟩

Article dans une revue hal-02129313v3
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Stochastic approximation of quasi-stationary distributions for diffusion processes in a bounded domain

Michel Benaïm , Nicolas Champagnat , Denis Villemonais

Annales de l'Institut Henri Poincaré (B) Probabilités et Statistiques, 2021, 57 (2), pp.726-739. ⟨10.1214/20-AIHP1093⟩

Article dans une revue hal-02101739v3
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Stochastic analysis of emergence of evolutionary cyclic behavior in population dynamics with transfer

Nicolas Champagnat , Sylvie Méléard , Viet Chi Tran

The Annals of Applied Probability, 2021, 31 (4), pp.1820-1867. ⟨10.1214/20-AAP1635⟩

Article dans une revue hal-01974289v3
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Lyapunov criteria for uniform convergence of conditional distributions of absorbed Markov processes

Nicolas Champagnat , Denis Villemonais

Stochastic Processes and their Applications, 2021, 135, pp.51-74. ⟨10.1016/j.spa.2020.12.005⟩

Article dans une revue hal-01503697v2
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Practical criteria for R-positive recurrence of unbounded semigroups

Nicolas Champagnat , Denis Villemonais

Electronic Communications in Probability, 2020, 25 (6), pp.1-11. ⟨10.1214/20-ECP288⟩

Article dans une revue hal-02101680v2
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Spatial eco-evolutionary dynamics along environmental gradients: multi-stability and cluster dynamics

Martín Andrade-Restrepo , Nicolas Champagnat , Régis Ferrière

Ecology Letters, 2019, 22 (5), pp.767-777

Article dans une revue hal-01732325v1
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A probabilistic approach to Dirac concentration in nonlocal models of adaptation with several resources

Nicolas Champagnat , Benoît Henry

The Annals of Applied Probability, 2019, 29 (4), pp.2175-2216. ⟨10.1214/18-AAP1446⟩

Article dans une revue hal-01651468v1
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On the link between infinite horizon control and quasi-stationary distributions

Nicolas Champagnat , Julien Claisse

Stochastic Processes and their Applications, 2019, 129 (3), pp.771-798. ⟨10.1016/j.spa.2018.03.018⟩

Article dans une revue hal-01349663v1
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Uniform convergence of penalized time-inhomogeneous Markov processes

Nicolas Champagnat , Denis Villemonais

ESAIM: Probability and Statistics, 2018, 22, pp.129-162. ⟨10.1051/ps/2017022⟩

Article dans une revue hal-01290222v1
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Uniform convergence of conditional distributions for absorbed one-dimensional diffusions

Nicolas Champagnat , Denis Villemonais

Advances in Applied Probability, 2018, 50 (1), pp.178-203. ⟨10.1017/apr.2018.9⟩

Article dans une revue hal-01166960v1
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Strong solutions to stochastic differential equations with rough coefficients

Nicolas Champagnat , Pierre-Emmanuel Jabin

The Annals of Probability, 2018, 46 (3), pp.1498-1541. ⟨10.1214/17-AOP1208⟩

Article dans une revue hal-00799242v2
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Uniform convergence to the Q-process

Nicolas Champagnat , Denis Villemonais

Electronic Communications in Probability, 2017, 22 (33), pp.1-7. ⟨10.1214/17-ECP63⟩

Article dans une revue hal-01395727v2

From stochastic, individual-based models to the canonical equation of adaptive dynamics - In one step

Martina Baar , Anton Bovier , Nicolas Champagnat

The Annals of Applied Probability, 2017, 27 (2), pp.1093-1170. ⟨10.1214/16-AAP1227⟩

Article dans une revue hal-01188189v1
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Exponential convergence to quasi-stationary distribution for absorbed one-dimensional diffusions with killing

Nicolas Champagnat , Denis Villemonais

ALEA : Latin American Journal of Probability and Mathematical Statistics, 2017, 14, pp.177-199. ⟨10.30757/ALEA.v14-11⟩

Article dans une revue hal-01217843v1
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On the variations of the principal eigenvalue with respect to a parameter in growth-fragmentation models

Fabien Campillo , Nicolas Champagnat , Coralie Fritsch

Communications in Mathematical Sciences, 2017, 15 (7), pp.1801-1819. ⟨10.4310/CMS.2017.v15.n7.a1⟩

Article dans une revue hal-01254053v3
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Moments of the frequency spectrum of a splitting tree with neutral Poissonian mutations

Nicolas Champagnat , Benoît Henry

Electronic Journal of Probability, 2016, 21 (53), pp.1-34. ⟨10.1214/16-EJP4577⟩

Article dans une revue hal-01202732v2
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Exponential convergence to quasi-stationary distribution and Q-process

Nicolas Champagnat , Denis Villemonais

Probability Theory and Related Fields, 2016, 164 (1), pp.243-283. ⟨10.1007/s00440-014-0611-7⟩

Article dans une revue hal-00973509v2
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Regime switching model for financial data: empirical risk analysis

Khaled Salhi , Madalina Deaconu , Antoine Lejay , Nicolas Champagnat , Nicolas Navet

Physica A: Statistical Mechanics and its Applications, 2016, 461, pp.148-157. ⟨10.1016/j.physa.2016.05.002⟩

Article dans une revue hal-01095299v2
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Links between deterministic and stochastic approaches for invasion in growth-fragmentation-death models

Fabien Campillo , Nicolas Champagnat , Coralie Fritsch

Journal of Mathematical Biology, 2016, 73 (6-7), pp.1781-1821. ⟨10.1007/s00285-016-1012-6⟩

Article dans une revue hal-01205467v1

Monte Carlo methods for linear and non-linear Poisson-Boltzmann equation

Mireille Bossy , Nicolas Champagnat , Helene Leman , Sylvain Maire , Laurent Violeau et al.

ESAIM: Proceedings, 2015, CEMRACS 2013, 48, pp.420-446. ⟨10.1051/proc/201448020⟩

Article dans une revue hal-01088930v1
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Adaptation in a stochastic multi-resources chemostat model

Nicolas Champagnat , Pierre-Emmanuel Jabin , Sylvie Méléard

Journal de Mathématiques Pures et Appliquées, 2014, 101 (6), pp.755-788. ⟨10.1016/j.matpur.2013.10.003⟩

Article dans une revue hal-00784166v2
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Splitting trees with neutral Poissonian mutations II: Largest and Oldest families

Nicolas Champagnat , Amaury Lambert

Stochastic Processes and their Applications, 2013, 123 (4), pp.1368-1414. ⟨10.1016/j.spa.2012.11.013⟩

Article dans une revue inria-00616765v2
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Simulation and analysis of an individual-based model for graph-structured plant dynamics

Fabien Campillo , Nicolas Champagnat

Ecological Modelling, 2012, 234 (10), pp.93-105. ⟨10.1016/j.ecolmodel.2012.03.017⟩

Article dans une revue inria-00526379v1
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On Dirichlet eigenvectors for neutral two-dimensional Markov chains

Nicolas Champagnat , Persi Diaconis , Laurent Miclo

Electronic Journal of Probability, 2012, 17 (63), pp.1-41. ⟨10.1214/EJP.v17-1830⟩

Article dans une revue hal-00672938v1
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Splitting trees with neutral Poissonian mutations I: Small families

Nicolas Champagnat , Amaury Lambert

Stochastic Processes and their Applications, 2012, 122 (3), pp.1003-1033. ⟨10.1016/j.spa.2011.11.002⟩

Article dans une revue inria-00515481v1
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Birth and death processes with neutral mutations

Nicolas Champagnat , Amaury Lambert , Mathieu Richard

International Journal of Stochastic Analysis, 2012, 2012, Article ID 569081, 20 p. ⟨10.1155/2012/569081⟩

Article dans une revue hal-00736036v2
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Reconciling alternate methods for the determination of charge distributions: A probabilistic approach to high-dimensional least-squares approximations

Nicolas Champagnat , Christophe Chipot , Erwan Faou

Journal of Mathematical Chemistry, 2011, Journal of Mathematical Chemistry, 49 (1), pp.296-324. ⟨10.1007/s10910-010-9740-0⟩

Article dans une revue inria-00345411v2
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Polymorphic evolution sequence and evolutionary branching

Nicolas Champagnat , Sylvie Méléard

Probability Theory and Related Fields, 2011, 151 (1-2), pp.45-94. ⟨10.1007/s00440-010-0292-9⟩

Article dans une revue inria-00345399v2
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The evolutionary limit for models of populations interacting competitively via several resources

Nicolas Champagnat , Pierre-Emmanuel Jabin

Journal of Differential Equations, 2011, 251 (1), pp.179-195. ⟨10.1016/j.jde.2011.03.007⟩

Article dans une revue inria-00488979v2
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Convergence to equilibrium in competitive Lotka-Volterra and chemostat systems

Nicolas Champagnat , Pierre-Emmanuel Jabin , Gael Raoul

Comptes rendus de l'Académie des sciences. Série I, Mathématique, 2010, 348 (23-24), pp.1267-1272. ⟨10.1016/j.crma.2010.11.001⟩

Article dans une revue inria-00495991v1
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Well-posedness in any dimension for Hamiltonian flows with non BV force terms

Nicolas Champagnat , Pierre-Emmanuel Jabin

Communications in Partial Differential Equations, 2010, 35 (5), pp.786-816. ⟨10.1080/03605301003646705⟩

Article dans une revue inria-00373784v2
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Probabilistic interpretation and random walk on spheres algorithms for the Poisson-Boltzmann equation in molecular dynamics

Mireille Bossy , Nicolas Champagnat , Sylvain Maire , Denis Talay

ESAIM: Mathematical Modelling and Numerical Analysis, 2010, 44 (5), pp.997-1048. ⟨10.1051/m2an/2010050⟩

Article dans une revue inria-00459411v1
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Large deviations for singular and degenerate diffusion models in adaptive evolution

Nicolas Champagnat

Markov Processes And Related Fields, 2009, 15 (3), pp.289-342

Article dans une revue inria-00368004v2
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Limit theorems for conditioned multitype Dawson-Watanabe processes and Feller diffusions

Nicolas Champagnat , Sylvie Roelly

Electronic Journal of Probability, 2008, 13 (25), pp.777-810

Article dans une revue inria-00164758v2

From Individual Stochastic Processes to Macroscopic Models in Adaptive Evolution

Nicolas Champagnat , Régis Ferrière , Sylvie Méléard

Stochastic Models, 2008, 24 (S1), pp.2-44. ⟨10.1080/15326340802437710⟩

Article dans une revue inria-00345680v1
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Evolution of discrete populations and the canonical diffusion of adaptive dynamics

Nicolas Champagnat , Amaury Lambert

The Annals of Applied Probability, 2007, 17 (1), pp.102-155. ⟨10.1214/105051606000000628⟩

Article dans une revue hal-00017951v2
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Invasion and adaptive evolution for individual-based spatially structured populations

Nicolas Champagnat , Sylvie Méléard

Journal of Mathematical Biology, 2007, 55 (2), pp.147-188. ⟨10.1007/s00285-007-0072-z⟩

Article dans une revue hal-00022153v2
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A microscopic interpretation for adaptive dynamics trait substitution sequence models

Nicolas Champagnat

Stochastic Processes and their Applications, 2006, 116 (8), pp.1127-1160. ⟨10.1016/j.spa.2006.01.004⟩

Article dans une revue hal-00015130v1
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Unifying evolutionary dynamics: from individual stochastic processes to macroscopic models

Nicolas Champagnat , Régis Ferrière , Sylvie Méléard

Theoretical Population Biology, 2006, 69 (3), pp.297-321. ⟨10.1016/j.tpb.2005.10.004⟩

Article dans une revue inria-00164784v1
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The canonical equation of adaptive dynamics: a mathematical view

Nicolas Champagnat , Régis Ferrière , Gérard Ben Arous

Selection, 2001, 2, pp.73-83

Article dans une revue inria-00164767v1
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Simulation d'expériences d'intervention biologique dans des cellules cancéreuses à partir de données temporelles d'expression de gènes

Anouk Rago , Nicolas Champagnat , Anne Gégout-Petit , Laurent Vallat

54es Journées de Statistique de la SFdS (JdS 2023), Société Française de Statistique, Jul 2023, Bruxelles, Belgique

Communication dans un congrès hal-04408929v1
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Multiscale eco-evolutionary models: from individuals to populations

Nicolas Champagnat , Sylvie Méléard , Viet Chi Tran

International Congress of Mathematicians, ICM 2022, Jul 2022, fully virtually, Russia. pp.5656-5678, ⟨10.4171/ICM2022/24⟩

Communication dans un congrès hal-04407958v1

Monte Carlo simulation and mathematical analysis of an individual-based model for clonal plant dynamics

Fabien Campillo , Nicolas Champagnat , Cendrine Mony

54th Symposium of the International Association for Vegetation Science (IAVS), Jun 2011, Lyon, France. n. p

Communication dans un congrès hal-00651732v1
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An individual-based model for clonal plant dynamics

Fabien Campillo , Nicolas Champagnat

4th International Conference on Approximation Methods and Numerical Modelling in Environment and Natural Resources (MAMERN11), May 2011, Saidia, Morocco. 4 p

Communication dans un congrès hal-00651837v1

Simulation and Analysis of a Markovian Individual-Based Model for Clonal Plant Dynamics

Fabien Campillo , Nicolas Champagnat

7th International Congress on Industrial and Applied Mathematics, Jul 2011, Vancouver, Canada. n.p

Communication dans un congrès hal-00651758v1
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Criteria for exponential convergence to quasi-stationary distributions and applications to multi-dimensional diffusions

Nicolas Champagnat , Koléhè Abdoulaye Coulibaly-Pasquier , Denis Villemonais

Séminaire de Probabilités XLIX, 2215, Springer, pp. 165-182, 2018, Lecture Notes in Mathematics, ⟨10.1007/978-3-319-92420-5_5⟩

Chapitre d'ouvrage hal-01293622v2
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Markov processes and parabolic partial differential equations

Mireille Bossy , Nicolas Champagnat

Cont Rama. Encyclopedia of Quantitative Finance, John Wiley & Sons Ltd. Chichester, UK, pp.1142-1159, 2010

Chapitre d'ouvrage inria-00193883v2
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Adaptive dynamics in logistic branching populations

Nicolas Champagnat , Amaury Lambert

Banach Center Publ., vol. 80, Polish Acad. Sci., pp.235-244, 2008, ⟨10.4064/bc80-0-14⟩

Chapitre d'ouvrage hal-00157987v1
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Individual-based probabilistic models of adaptive evolution and various scaling approximations

Nicolas Champagnat , Régis Ferrière , Sylvie Méléard

Robert C. Dalang, Marco Dozzi, Francesco Russo. Seminar on Stochastic Analysis, Random Fields and Applications V, Birkhaüser, pp.75-114, 2008, Progress in Probability, Vol. 59, 978-3-7643-8458-6

Chapitre d'ouvrage hal-00011146v2
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Processus de Galton-Watson et applications en dynamique des populations

Nicolas Champagnat

Master. École Supérieure des Sciences et Technologies de Hammam Sousse, Tunisie. 2015, pp.46

Cours cel-01216832v1
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Différences finies et analyse numérique matricielle

Nicolas Champagnat

Master. France. 2010, pp.51

Cours cel-01188281v1