PTab: Using the Pre-trained Language Model for Modeling Tabular Data
This addresses the challenge of modeling tabular data for machine learning practitioners by leveraging semantic knowledge from language models, though it is incremental as it adapts existing pre-trained models to a new modality.
The authors tackled the problem of learning effective contextual representations from tabular data with limited semantic information and dataset size, proposing PTab, a framework that uses pre-trained language models, which achieved better average AUC scores than state-of-the-art baselines like XGBoost in supervised settings and outperformed counterparts in semi-supervised settings.
Tabular data is the foundation of the information age and has been extensively studied. Recent studies show that neural-based models are effective in learning contextual representation for tabular data. The learning of an effective contextual representation requires meaningful features and a large amount of data. However, current methods often fail to properly learn a contextual representation from the features without semantic information. In addition, it's intractable to enlarge the training set through mixed tabular datasets due to the difference between datasets. To address these problems, we propose a novel framework PTab, using the Pre-trained language model to model Tabular data. PTab learns a contextual representation of tabular data through a three-stage processing: Modality Transformation(MT), Masked-Language Fine-tuning(MF), and Classification Fine-tuning(CF). We initialize our model with a pre-trained Model (PTM) which contains semantic information learned from the large-scale language data. Consequently, contextual representation can be learned effectively during the fine-tuning stages. In addition, we can naturally mix the textualized tabular data to enlarge the training set to further improve representation learning. We evaluate PTab on eight popular tabular classification datasets. Experimental results show that our method has achieved a better average AUC score in supervised settings compared to the state-of-the-art baselines(e.g. XGBoost), and outperforms counterpart methods under semi-supervised settings. We present visualization results that show PTab has well instance-based interpretability.