The H-IAR Model for Irregular Multispectral Time Series. Quaternion Formulation, Mapping of Resilience Indicators, and Exploratory Identification of Forest Edges
不规则多光谱时间序列的 H-IAR 模型：四元数表述、韧性指标制图与森林边缘探索
We propose the Hypercomplex Irregular Autoregressive (\HIAR) model, a quaternion extension of the \IAR/\CIAR/\BIAR{} family for four-component observations at irregular times. Temporal dependence is represented by a real power of a quaternion parameter and estimated in state-space form through the Gaussian innovation likelihood of the Kalman filter, conditional on the adopted covariance specifications. Across 12,000 Monte Carlo fits, mean absolute bias decreased with sample…