Key Points

The paper "Large Language Models (LLMs) on Tabular Data: Prediction, Generation, and Understanding - A Survey" provides a comprehensive review of recent advancements in modeling tabular data using LLMs. The survey covers characteristics and challenges of tabular data, traditional and deep learning methods in tabular data, large language models (LLMs), and their applications in tabular data, key techniques for LLMs' applications on tabular data, and opportunities for LLMs in tabular data modeling.

The survey discusses the emergence of large language models (LLMs) in various tasks related to tabular data modeling. It sheds light on the remarkable performance of LLMs, their abilities for in-context learning, instruction following, and multi-step reasoning, and their capabilities to generate human-readable responses and code readable by other programs. Additionally, the survey outlines the key challenges and opportunities for LLMs in the tabular data domain.

Regarding the specific task of tabular data prediction, the paper presents different preprocessing techniques, such as serialization, table manipulation, and prompt engineering. For feature-based tabular data prediction, it details methods like LIFT, TABLET, TabLLM, and UniPredict. The survey discusses the advantages and challenges of using LLMs for time series prediction, including preprocessing and fine-tuning methods for time series forecasting.

In terms of target augmentation, various methods are explored, such as using special tokens, verbalizer, and serialization of target classes and probabilities. The survey emphasizes the importance of reporting common metrics such as AUC for classification prediction and RMSE for regression, calling for the need to benchmark different methods for new preprocessing and prediction techniques.

The paper includes examples and details of various techniques and methodologies used in the survey, providing a broad overview of the state-of-the-art methods and the current landscape of large language models in tabular data modeling.

1. Medical Prediction: LLMs such as DeBERTa have been found to outperform XGBoost in electronic health record (EHR) prediction tasks, utilizing GPT-3.5 for preprocessing and BioBert classifier for fine-tuning. They demonstrate superior performance in supervised, few-shot, and zero-shot learning scenarios in the medical domain, particularly on imbalanced medical datasets.

2. Financial Prediction: FinPT presents an LLM-based approach for financial risk prediction, employing ChatGPT and GPT-4 to fine-tune large foundation models like BERT. Flan-T5 emerges as the most effective backbone model across eight datasets, demonstrating improved performance in financial risk prediction tasks.

3. Recommendation Prediction: CTRL proposes a novel method for Click Through Rate (CTR) prediction by converting tabular data into text, feeding them into a collaborative CTR model, and fine-tuning a lightweight collaborative model for downstream tasks. The approach outperforms all the state-of-the-art baselines across three datasets by a significant margin in combining collaborative and semantic signals.

4. Data Synthesis Methods: GReaT, REaLTabFormer, and TAPTAP are proposed methods for generating synthetic tabular data with original characteristics. These methods use textual encoding, autoregressive GPT-2 models, and pre-fine-tuning the GPT2 on various datasets, showcasing the potential of LLMs for data synthesis.

5. Quality Evaluation: Several dimensions, including low-order statistics, high-order metrics, privacy preservation, performance on downstream tasks, and model interpretability, are crucial for evaluating the quality of synthetic data and LLM performance in tabular QA tasks.

6. QA Datasets: FetaQA, NQ-Tables, and HybriDialogue are recommended datasets that require deeper reasoning and integration of information for tabular question answering tasks, addressing a significant challenge in current dialogue systems.

7. Text2SQL: Systems like TAPEX and WIKISQL aim to create a SQL executor, allowing the generation and execution of SQL queries from tabular and textual inputs. They have been benchmarked by many existing methods and are suitable for various types of meaning representations.

8. Limitations: Concerns such as bias and fairness, hallucination, numerical and categorical representation, standard benchmark, model interpretability, usability, fine-tuning strategy design, and model grafting are important factors that impact the performance and practical applicability of LLMs for tabular data modeling.

9. Future Research: With the remarkable capabilities and limitations of LLMs for modeling heterogeneous tabular data, there is a growing demand for new ideas and research to explore their potential in various tasks, addressing challenges in fairness, hallucination, interpretability, and usability.

Summary

Introduction to Large Language Models in Tabular Data Modeling
The survey paper consolidates recent advancements in utilizing large language models (LLMs) for diverse tasks related to tabular data modeling, encompassing prediction, tabular data synthesis, question answering, and table understanding. The paper addresses the lack of a comprehensive review and comparison of the key techniques, metrics, datasets, models, and optimization approaches in this research domain. LLMs, which are deep learning models trained on extensive data, have proven to be versatile in problem-solving capabilities, extending beyond the realm of natural language processing tasks. The survey also explores the unique challenges and opportunities presented by tabular data, such as heterogeneity, sparsity, dependency on pre-processing, context-based interconnection, order invariance, and lack of prior knowledge. Additionally, the paper discusses traditional and deep learning methods in tabular data and the recent advancements in large language models and their applications in tabular data modeling.

Key Techniques and Future Directions for LLMs in Tabular Data Applications
The review paper further elucidates the key techniques for LLMs' applications on tabular data, including serialization, table manipulations, prompt engineering, and target augmentation. It encompasses extensive insights into recent advancements and future directions in utilizing LLMs for diverse tabular data tasks, providing clarity and guidance to interested researchers and practitioners in the field. Furthermore, the paper proposes a taxonomy for techniques and metrics utilized in LLMs' applications on tabular data, shedding light on comprehensive and thorough surveying and classification of datasets and methodologies. The authors offer a comprehensive overview of key open problems and challenges that future work should address, aiming to propel advancements in the field of large language models and their applications in tabular data modeling.

Comprehensive Exploration of LLMs in Tabular Data Modeling
In essence, the survey paper presents a holistic and systematic exploration of recent breakthroughs in LLMs' applications on tabular data modeling, aiming to provide interested readers, researchers, and practitioners with pertinent references, insightful perspectives, and the necessary tools and knowledge to effectively navigate and address the prevailing challenges in the field. Through the consolidation of recent progress, the paper offers significant contributions by organizing key techniques, metrics, datasets, and methodologies for the application of LLMs in diverse tabular data tasks, paving the way for future research directions and advancements in the field.

Utilization of LLMs in Modeling Heterogeneous Tabular Data
The survey paper extensively explores the utilization of Large Language Models (LLMs) in modeling heterogeneous tabular data, covering tasks including prediction, data synthesis, question answering, and table understanding. The authors discuss crucial steps for ingesting tabular data by LLMs, including serialization, table manipulation, and prompt engineering. For each task, the paper systematically compares datasets, methodologies, metrics, and models, addressing challenges and recent advancements.

Evaluation of LLMs in Task Application Scenarios
In the realm of task application, the study evaluates LLMs across supervised, few-shot, and zero-shot learning scenarios within the medical domain, demonstrating superior performance compared to gradient boosting methods and existing LLM-based approaches. Financial Prediction FinPT presents an LLM-based approach to financial risk prediction using models such as ChatGPT and GPT-4. The research also explores a novel method for Click Through Rate (CTR) prediction by converting tabular data into text using human-designed prompts.

Examination of Data Synthesis Methods and Question Answering
Moreover, the paper meticulously examines data synthesis methods, emphasizing the pivotal role of nuanced datasets for tabular data augmentation. It encompasses various methods such as REaLTabFormer, TAPTAP, and GReaT, elucidating their characteristics and performance in generating synthetic non-relational and relational tabular data. The paper also comprehensively covers datasets, trends, and methods for question answering and fact verification tasks.

Limitations and Challenges of Current Approaches
Additionally, the paper delves into the limitations of current approaches, such as bias and fairness concerns, hallucination, numerical and categorical representation challenges, and issues with model interpretability. It emphasizes the need for standardized benchmark datasets, model interpretability, and user-friendly usage, indicating directions for future research and exploration to address prevailing challenges in the field.

Conclusion and Future Research Directions
The survey aims to provide scholars and practitioners with pertinent references and insightful perspectives to effectively navigate and address challenges in utilizing LLMs for modeling structured data, highlighting the growing demand for new ideas and research to explore the potential of LLMs in tabular data modeling.



Reference: https://arxiv.org/abs/2402.179...