Stefan Leknes - Moving beyond expectations: from cohort-component to microsimulation projections

• Presenting author: Stefan Leknes (Statistics Norway)

• Authors: Zhiyang Jia, Stefan Leknes and Sturla A. Løkken

• Session: B02A - Population [2] - Tuesday 11:00-12:30 - Ceremonial Hall

Population projections are predominantly made using the cohort-component method (CCM). The framework faces difficulties in accommodating additional population heterogeneity, which limits opportunities for further development. Lately, with advances in technical and computational capacity, the microsimulation framework has become a serious contender. In contrast to CCM, it allows for rich complexity of behavior and provides insights on projection uncertainty. Still, demographers have been reluctant to apply this framework, which may be due to lack of guidance. We contribute by clarifying underlying CCM assumptions, translating a multi-regional version of the model into a dynamic spatial microsimulation model, and discuss the usefulness of prediction intervals for planning. Using data for Norway, we demonstrate that the results for the two models are equivalent, even for very small subgroups, and converge with relatively few simulations. The model can easily be amended with additional individual heterogeneity, facilitating more accurate representations of population dynamics.