Enhancing Tabular Data Optimization with a Flexible Graph-based Reinforced Exploration Strategy

TL;DR

This paper introduces a graph-based reinforcement strategy for automated feature engineering in tabular data, improving exploration efficiency and robustness by leveraging transformation history and backtracking.

Contribution

It proposes a novel feature-state transformation graph with cascading agents, enabling dynamic backtracking and better utilization of historical decisions for feature optimization.

Findings

Outperforms existing methods in diverse scenarios

Enhances exploration efficiency and robustness

Demonstrates superior feature transformation quality

Abstract

Tabular data optimization methods aim to automatically find an optimal feature transformation process that generates high-value features and improves the performance of downstream machine learning tasks. Current frameworks for automated feature transformation rely on iterative sequence generation tasks, optimizing decision strategies through performance feedback from downstream tasks. However, these approaches fail to effectively utilize historical decision-making experiences and overlook potential relationships among generated features, thus limiting the depth of knowledge extraction. Moreover, the granularity of the decision-making process lacks dynamic backtracking capabilities for individual features, leading to insufficient adaptability when encountering inefficient pathways, adversely affecting overall robustness and exploration efficiency. To address the limitations observed in current automatic feature engineering frameworks, we introduce a novel method that utilizes a feature-state transformation graph to effectively preserve the entire feature transformation journey, where each node represents a specific transformation state. During exploration, three cascading agents iteratively select nodes and idea mathematical operations to generate new transformation states. This strategy leverages the inherent properties of the graph structure, allowing for the preservation and reuse of valuable transformations. It also enables backtracking capabilities through graph pruning techniques, which can rectify inefficient transformation paths. To validate the efficacy and flexibility of our approach, we conducted comprehensive experiments and detailed case studies, demonstrating superior performance in diverse scenarios.