Probabilistic hierarchical time-series forecasting is an important variant of time-series forecasting, where the goal is to model and forecast multivariate time-series that have underlying hierarchical relations. Most methods focus on point predictions and do not provide well-calibrated probabilistic forecasts distributions. Recent state-of-art probabilistic forecasting methods also impose hierarchical relations on point predictions and samples of distribution which does not account for coherency of forecast distributions. Previous works also silently assume that datasets are always consistent with given hierarchical relations and do not adapt to real-world datasets that show deviation from this assumption. We close both these gap and propose PROFHiT, which is a fully probabilistic hierarchical forecasting model that jointly models forecast distribution of entire hierarchy. PROFHiT uses a flexible probabilistic Bayesian approach and introduces a novel Distributional Coherency regularization to learn from hierarchical relations for entire forecast distribution that enables robust and calibrated forecasts as well as adapt to datasets of varying hierarchical consistency. On evaluating PROFHiT over wide range of datasets, we observed 41-88% better performance in accuracy and significantly better calibration. Due to modeling the coherency over full distribution, we observed that PROFHiT can robustly provide reliable forecasts even if up to 10% of input time-series data is missing where other methods' performance severely degrade by over 70%.

PROFHiT是一种完全概率性的分层预测模型，通过灵活的概率贝叶斯方法和引入新颖的分布一致性正则化，能够从分层关系中学习整个预测分布，从而实现鲁棒和校准的预测，并适应具有不同分层一致性的数据集。评估结果显示，PROFHiT在准确性方面表现出了41-88%的改进，并且具有更好的校准性。此外，由于对整个分布的一致性建模，当输入时间序列数据缺失10%时，PROFHiT仍然能够提供可靠的预测，而其他方法的性能会下降超过70%。

刚性的伤害：概率层次时间序列预测的软一致性正则化