Estimation of fertility rates using functional data and small area estimation techniques

E. López Vizcaíno, M. J. Lombardía Cortiña, C. Rueda Sabater

Accurate municipal fertility estimates are vital for demographic planning, but small-area projections are difficult because of sparse and highly variable data. This study improves fertility rate estimation for Galician municipalities from 2002 to 2022 by combining Functional Data Analysis (FDA) and Small Area Estimation (SAE).
We propose a novel Frequency Modulated Möbius (FMM) model that offers a flexible, interpretable way to capture fertility trends. Its performance is compared with existing methods through simulations and real data. Results show that FMM-based models outperform alternatives, producing smoother fertility curves and lower RMSE.
For forecasts over 2023–2032, FMM models also perform best, indicating a continued decline in fertility and a shift towards later childbearing in most municipalities. Cross-validation confirms the robustness and reliability of the approach for small-area fertility estimation and forecasting.

Palabras clave: fertility rates, small area estimation, Frequency Modulated Möbius

SI SGAPEIO - SEIO
2 de septiembre de 2026  12:40
Aula 29

J. M. Alonso Meijide, M. Alvarez Mozos, M. G. Fiestras Janeiro, A. Jiménez Losada

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