Feature Interaction Aware Automated Data Representation Transformation
Ehtesamul Azim, Dongjie Wang, Kunpeng Liu, Wei Zhang, Yanjie Fu
TL;DR
This work addresses the interpretability and efficiency gaps in automated feature engineering by introducing InHRecon, an Interaction-aware Hierarchical Reinforced Feature Space Reconstruction framework. It formulates feature reconstruction as nested generation and selection managed by three MDPs (one operation agent and two feature agents) within a hierarchical RL setup, and it uses an expanded operator set along with H-statistics to reward informative feature interactions. The approach yields a traceable, explainable feature generation process and demonstrates strong empirical results across 24 datasets, with ablations confirming the value of interaction-aware rewards and hierarchical coordination. Overall, InHRecon advances scalable, interpretable AutoFE by aligning automated feature construction with human-like cognition and statistical guidance, showing robustness across downstream models and tasks.
Abstract
Creating an effective representation space is crucial for mitigating the curse of dimensionality, enhancing model generalization, addressing data sparsity, and leveraging classical models more effectively. Recent advancements in automated feature engineering (AutoFE) have made significant progress in addressing various challenges associated with representation learning, issues such as heavy reliance on intensive labor and empirical experiences, lack of explainable explicitness, and inflexible feature space reconstruction embedded into downstream tasks. However, these approaches are constrained by: 1) generation of potentially unintelligible and illogical reconstructed feature spaces, stemming from the neglect of expert-level cognitive processes; 2) lack of systematic exploration, which subsequently results in slower model convergence for identification of optimal feature space. To address these, we introduce an interaction-aware reinforced generation perspective. We redefine feature space reconstruction as a nested process of creating meaningful features and controlling feature set size through selection. We develop a hierarchical reinforcement learning structure with cascading Markov Decision Processes to automate feature and operation selection, as well as feature crossing. By incorporating statistical measures, we reward agents based on the interaction strength between selected features, resulting in intelligent and efficient exploration of the feature space that emulates human decision-making. Extensive experiments are conducted to validate our proposed approach.
