Optimizing Sentence Embedding with Pseudo-Labeling and Model Ensembles: A Hierarchical Framework for Enhanced NLP Tasks
Ziwei Liu, Qi Zhang, Lifu Gao
TL;DR
This paper addresses the challenge of producing reliable sentence embeddings when data are limited and domain variation is high. It introduces a hierarchical framework that fuses pseudo-labeling, external corpora (SimpleWiki, Wikipedia, BookCorpus), and model ensembles using backbones ALBERT-xxlarge, RoBERTa-large, and DeBERTa-large. Key contributions include a three-stage model (encoding, refinement, ensemble), cross-attention with external context, data augmentation, and an error-aware pseudo-labeling pipeline, yielding substantial gains over baselines. The approach provides a robust, generalizable blueprint for enhanced sentence embeddings applicable to cross-lingual and real-time NLP tasks.
Abstract
Sentence embedding tasks are important in natural language processing (NLP), but improving their performance while keeping them reliable is still hard. This paper presents a framework that combines pseudo-label generation and model ensemble techniques to improve sentence embeddings. We use external data from SimpleWiki, Wikipedia, and BookCorpus to make sure the training data is consistent. The framework includes a hierarchical model with an encoding layer, refinement layer, and ensemble prediction layer, using ALBERT-xxlarge, RoBERTa-large, and DeBERTa-large models. Cross-attention layers combine external context, and data augmentation techniques like synonym replacement and back-translation increase data variety. Experimental results show large improvements in accuracy and F1-score compared to basic models, and studies confirm that cross-attention and data augmentation make a difference. This work presents an effective way to improve sentence embedding tasks and lays the groundwork for future NLP research.
