arXiv AI

GRAIL: From Saliency to Semantics in Time-Series Explanation

GRAIL is a region‑based framework for explaining time‑series models that moves beyond per‑timestep saliency by treating domain‑specific intervals—such as the P‑wave and QRS complex in ECG data—as players in a cooperative game. It describes each region with human‑readable features, generates counterfactual baselines using an on‑manifold conditional generator, and incorporates static covariates as singleton players to directly weigh tabular evidence against the signal. The method attributes predictions via Owen values with variance reduction, and experiments on synthetic and real data demonstrate faithful, robust explanations that provide meaningful knowledge to domain experts.

arXiv AI
Aug 24

GroupSegment-SHAP: Shapley Value Explanations with Group-Segment Players for Multivariate Time Series

GroupSegment-SHAP (GS‑SHAP) introduces explanatory units called group‑segment players that capture cross‑variable dependence and distribution shifts over time in multivariate time‑series models. By attributing Shapley values to these units, GS‑SHAP preserves joint structural signals that traditional time‑series SHAP variants fragment. Experiments on human activity recognition, power‑system forecasting, medical signal analysis, and financial time series show that GS‑SHAP improves deletion‑based faithfulness by about 1.7× and reduces runtime by roughly 40% compared to existing baselines, while a financial case study demonstrates its ability to reveal interpretable multivariate‑temporal interactions during high‑volatility periods.

By Jinwoong Kim, Sangjin Park
arXiv Machine Learning
Aug 27

NVExplain: Explaining Time Series Forecasting with Latent Trajectory Analysis and Structure-Preserving Surrogates

NVExplain is a model‑agnostic framework that explains time‑series forecasting by attributing each forecast horizon to temporally relevant historical lags. It models forecasting as a latent trajectory, introduces semantic flow to track information evolution, and aggregates this into a lag‑horizon attribution matrix. The method also generates structure‑preserving perturbations and fits sparse local surrogates to produce human‑readable, temporally coherent explanations, and demonstrates competitive faithfulness and stability across benchmark datasets.

By Muyan Anna Li, Manikandan Ravikiran, Aditi Gautam
arXiv AI
Oct 16

Twice Upon a Time: Complementary Representations for Time-Series Reasoning

The paper introduces a dual‑view approach for time‑series language models, combining line plots that preserve absolute measurements with normalized delay embeddings that highlight temporal structure. By fusing these complementary visual representations through dedicated encoders and multi‑level feature fusion, the model achieves significant performance gains on several benchmarks, outperforming single‑view baselines and existing TSLMs. The results demonstrate that preserving both measurement frame and temporal structure is an effective design principle for general‑purpose time‑series reasoning.

By Hedi Zisling, Liran Nochumsohn, Ilan Naiman, Mihir Parmar, Omri Azencot