Robust non-parametric mortality and fertility modelling and forecasting: Gaussian process regression approaches

TL;DR

This paper presents a novel non-parametric Gaussian process regression method for more accurate and robust forecasting of mortality and fertility rates, addressing limitations of traditional models by considering age-specific components.

Contribution

It introduces a Gaussian process-based approach with a spectral mixture covariance function for demographic curve modeling, improving forecast accuracy and robustness.

Findings

Significant improvements in forecast precision over existing methods

Enhanced robustness in short-, mid-, and long-term predictions

Effective modeling of age-specific mortality and fertility rates

Abstract

A rapid decline in mortality and fertility has become major issues in many developed countries over the past few decades. A precise model for forecasting demographic movements is important for decision making in social welfare policies and resource budgeting among the government and many industry sectors. This article introduces a novel non-parametric approach using Gaussian process regression with a natural cubic spline mean function and a spectral mixture covariance function for mortality and fertility modelling and forecasting. Unlike most of the existing approaches in demographic modelling literature, which rely on time parameters to decide the movements of the whole mortality or fertility curve shifting from one year to another over time, we consider the mortality and fertility curves from their components of all age-specific mortality and fertility rates and assume each of them following a Gaussian process over time to fit the whole curves in a discrete but intensive style. The proposed Gaussian process regression approach shows significant improvements in terms of preciseness and robustness compared to other mainstream demographic modelling approaches in the short-, mid- and long-term forecasting using the mortality and fertility data of several developed countries in our numerical experiments.