BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20250717T164759EDT-2705cuSg38@132.216.98.100 DTSTAMP:20250717T204759Z DESCRIPTION:Lambda-coalescent and lookdown model with selection\n\nWe study the lookdown model with selection in the case of a population containing two types of individuals\, where the genealogy backward in time is describ ed by the standard Lambda-coalescent with a non-trivial 'Kingman part'. We show that the proportion of one of the two types converges\, as the popul ation size N tends to infinity\, towards the solution to a stochastic diff erential equation driven by a Poisson point process (the same equation\, i n case without selection\, already appeared in the work of Bertoin and Le Gall). We show that one of the two types fixates in finite time if and onl y if the Lambda-coalescent comes down from infinity. In the case of no fix ation\, we prove that for a certain selection pressure\, the disadvantage allele will vanish asymptotically with probability one. This phenomenon ca nnot occur in the classical Wright-Fisher diffusion. We give precise asymp totic results in the case of the Bolthausen-Sznitman coalescent. In partic ular we obtain in that case an explicit formula for the probability that o ne of the two alleles fixates\, which is different from the classical one for the Wright-Fisher model.\n DTSTART:20180129T190000Z DTEND:20180129T200000Z LOCATION:Room 1214\, Burnside Hall\, CA\, QC\, Montreal\, H3A 0B9\, 805 rue Sherbrooke Ouest SUMMARY:Boubacar Bah\, AIMS-Cameroon URL:/mathstat/channels/event/boubacar-bah-aims-cameroo n-284243 END:VEVENT END:VCALENDAR