https://door.donau-uni.ac.at/o:5685 Innovations in methodological approaches to estimate irregular migrant stocks and flows Rodríguez-Sánchez, Alejandra Alejandra Rodríguez-Sánchez University of Potsdam Tjaden, Jasper Jasper Tjaden 0000-0002-5054-3535 University of Potsdam text eng Key points • This chapter builds on Rodríguez-Sánchez and Tjaden (2023), who reviewed the main methods for estimating irregular migrant stocks and flows, spanning both established and more experimental approaches. • Measuring irregular migration remains a fundamental challenge: the population is difficult to observe, and even widely used methods such as residual estimation or capture–recapture provide only partial pictures. • Traditional techniques continue to form the backbone of the field, but improvements have often come from incremental innovations, such as using mortality data to refine life-course approaches, or expanding residual methods with large government databases and machine learning. • More novel directions, such as exploiting consular registers, driver’s licence data, or online search behaviour, show promise in filling gaps, though these remain context-specific and experimental. Estimation methods Irregular migration stocks and flows Innovative data sources http://creativecommons.org/licenses/by-nc/4.0/ https://door.donau-uni.ac.at/api/object/o:5685/download 10.48341/g31s-vq79-05 https://door.donau-uni.ac.at/o:5698 application/pdf 65 74 1.49 MB 2025-09-30