This paper presents several forecasting methods to model and forecast subnational age distribution of death counts. The age distribution of death counts has many similarities to probability density functions, which are nonnegative and have a constrained integral, and thus live in a constrained nonlinear space. To address the nonlinear nature of objects, we implement a cumulative distribution function transformation that has an additional monotonicity. Using the Japanese subnational life-table death counts obtained from the Japanese Mortality Database (2025), we evaluate the forecast accuracy of the transformation and forecasting methods. The improved forecast accuracy of life-table death counts implemented here will be of great interest to demographers in estimating regional age-specific survival probabilities and life expectancy.

翻译：本文提出了几种预测亚国家级死亡人数年龄分布的方法。死亡人数的年龄分布与概率密度函数有许多相似之处，即非负且积分受限，因此存在于一个受限的非线性空间中。为处理对象的非线性特性，我们实现了一种具有额外单调性的累积分布函数变换。利用从日本死亡率数据库（2025）获得的日本亚国家级生命表死亡人数数据，我们评估了该变换及预测方法的预测精度。本文实现的改进的生命表死亡人数预测精度，对于人口学家在估计区域年龄别生存概率和预期寿命方面具有重要意义。