BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20250918T093913EDT-6628OhhCUB@132.216.98.100 DTSTAMP:20250918T133913Z DESCRIPTION:Title:\n\nStatistical inference in surveys with random forest i mputed estimators\n\nAbstract: \n\nSurvey sampling is concerned with the e stimation of finite population parameters. Most often\, the survey variabl e is only partially observed due to missing data. In surveys\, item nonres ponse is usually handled through some form of imputation\, a procedure con sisting of replacing missing values with predicted values. In recent years \, imputation through machine learning procedures has attracted a lot of a ttention in national statistical offices. However\, little is known about the theoretical properties of the resulting point estimators. In this talk \, we will investigate the properties of regression trees and random fores ts imputed estimators in surveys. The asymptotic properties of these estim ators will be discussed. Variance estimation will be investigated: we will show that traditional variance estimators may be biased for some configur ation of hyper-parameters and suggest a novel variance estimator based on a K-fold cross-validation procedure. A simulation study will be presented to assess the performances of the proposed point and variance estimators. Finally\, the choice of hyper-parameters in random forest algorithms will be discussed through a mix of theoretical and empirical results.\n DTSTART:20230918T200000Z DTEND:20230918T210000Z LOCATION:Room 1104\, Burnside Hall\, CA\, QC\, Montreal\, H3A 0B9\, 805 rue Sherbrooke Ouest SUMMARY:Mehdi Dagdoug (9IÖÆ×÷³§Ãâ·Ñ) URL:/mathstat/channels/event/mehdi-dagdoug-mcgill-univ ersity-350551 END:VEVENT END:VCALENDAR