关键词: 人口不确定性, 随机人口预测, 确定性预测, 人口规划

Abstract: The future is uncertain, and so are the future populations. This uncertainty is a fundamental aspect of population dynamics. It is affected by various factors such as socio-economic development, technological advances, and even cultural change. Understanding demographic uncertainty is essential in policy-making based on population projection. In recent decades, various methods have been developed to describe the uncertainty, including probabilistic forecast. However, such methods have not got enough attention in China, where the population tends to be highly uncertain due to rapid demographic transition and social transformation. In this paper, we investigate the uncertainty and its policy implications. Specifically, we focus on three major aspects of China's population:the number of births, particularly in the era of universal two-child policy, the number of total population, and the target population of regional planning. Overlooking or underestimating demographic uncertainty can lead to misleading projection results for policy makers and the public. We are in need of developing methods for China's population projections.

Keywords: Demographic Uncertainty, Stochastic Forecasts, Deterministic Projection, Population Planning