Université Paris 6
Pierre et Marie Curie | Université Paris 7
Denis Diderot | |

CNRS U.M.R. 7599
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``Probabilités et Modèles Aléatoires''
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**Auteur(s): **

**Code(s) de Classification MSC:**

- 60G09 Exchangeability
- 60J25 Markov processes with continuous parameter
- 92D30 Epidemiology

**Résumé:** We obtain precise information about the
stochastic flows of bridges that
are associated with the so-called $\Lambda$-coalescents. When the
measure
$\Lambda$ gives no mass to $0$, we prove that the flow of bridges is
generated by a stochastic differential equation
driven by a Poisson point process. On the other
hand, the case $\Lambda=\delta_0$ of
the Kingman coalescent gives rise to a flow of coalescing diffusions
on the interval $[0,1]$.
We also discuss a remarkable Brownian flow on the circle which
has close connections with the Kingman coalescent

**Mots Clés:** *Flow ; coalescence ; bridge ; stochastic differential equation*

**Date:** 2004-02-09

**Prépublication numéro:** *PMA-881*