Using a Local Surrogate Model to Interpret Temporal Shifts in Global Annual Data
Shou Nakano, Yang Liu
TL;DR
This work tackles the challenge of explaining temporal shifts in globally sourced annual data by applying Local Interpretable Model-agnostic Explanations (LIME) to multivariate time-series across countries. It integrates multiple imputation strategies, FLAML-based model training, and ICE validation to produce interpretable explanations for happiness, economic freedom, and population dynamics. Through three open datasets and case studies (notably Syria and Brazil), the approach demonstrates that LIME can identify influential drivers and that its explanations align with real-world events, offering potential policy and economic planning insights. The study highlights the practical viability of combining local surrogates with automated model selection to make complex temporal predictions more transparent and actionable.
Abstract
This paper focuses on explaining changes over time in globally-sourced, annual temporal data, with the specific objective of identifying pivotal factors that contribute to these temporal shifts. Leveraging such analytical frameworks can yield transformative impacts, including the informed refinement of public policy and the identification of key drivers affecting a country's economic evolution. We employ Local Interpretable Model-agnostic Explanations (LIME) to shed light on national happiness indices, economic freedom, and population metrics, spanning variable time frames. Acknowledging the presence of missing values, we employ three imputation approaches to generate robust multivariate time-series datasets apt for LIME's input requirements. Our methodology's efficacy is substantiated through a series of empirical evaluations involving multiple datasets. These evaluations include comparative analyses against random feature selection, correlation with real-world events as elucidated by LIME, and validation through Individual Conditional Expectation (ICE) plots, a state-of-the-art technique proficient in feature importance detection.
