Supervised Learning of Universal Sentence Representations from Natural Language Inference Data

TL;DR

InferSent, a supervised framework using SNLI data, achieves superior sentence representation transfer performance.

cs.CL 🟡 Intermediate 2017-05-06 35 views
Alexis Conneau Douwe Kiela Holger Schwenk Loic Barrault Antoine Bordes
NLP sentence representation transfer learning supervised learning SNLI dataset

Key Findings

Methodology

The study uses supervised learning on SNLI data, employing a BiLSTM-Max architecture to generate universal sentence representations. The framework encodes premise and hypothesis sentences separately, extracting semantic relations using concatenation, element-wise product, and absolute difference.

Key Results

  • BiLSTM-Max outperformed SkipThought-LN across 12 transfer tasks, achieving a Pearson correlation of 0.68 on STS14 semantic similarity.
  • Training time reduced significantly to one day compared to SkipThought's one month.
  • Achieved 84.5% accuracy on SNLI test set, with a micro-average transfer accuracy of 85.2%.

Significance

This research validates natural language inference (NLI) as an effective supervised task for generating universal sentence representations, addressing limitations of unsupervised methods in transfer tasks and paving the way for efficient representation generation.

Technical Contribution

Introduced a supervised framework leveraging NLI tasks, significantly improving transfer performance. Compared to unsupervised methods like SkipThought, it reduces training time and computational resources while achieving higher accuracy.

Novelty

First to systematically exploit SNLI for supervised sentence representation learning, demonstrating NLI's semantic reasoning suitability for transfer tasks, filling a key research gap.

Limitations

  • Relies on high-quality labeled datasets, limiting applicability to low-resource languages.
  • Potential overfitting to specific tasks may hinder generalization.
  • Performance on non-English datasets remains unexplored.

Future Work

Future directions include developing multilingual NLI datasets and combining unsupervised methods to enhance generalization capabilities.

AI Executive Summary

Existing unsupervised sentence representation methods, such as SkipThought, struggle with transfer tasks due to limited semantic reasoning and lengthy training times.

This paper introduces InferSent, a supervised framework leveraging SNLI data and a BiLSTM-Max architecture to generate universal sentence representations. The model extracts semantic relations via max-pooling and three matching methods, achieving superior transfer performance.

Experiments demonstrate significant improvements across multiple tasks, including sentiment analysis and semantic similarity, while drastically reducing training time. This work lays the foundation for efficient sentence representation generation and opens avenues for multilingual and hybrid approaches in the future.

Deep Analysis

Background

Sentence representation is a cornerstone of NLP, aiming to encode sentences into fixed-length vectors capturing semantic meaning. Traditional methods like SkipThought rely on unsupervised learning but face limitations in transfer tasks and require extensive training time.

Core Problem

Unsupervised methods struggle to capture higher-level semantic relationships, leading to suboptimal transfer performance. Additionally, the lack of suitable supervised tasks for universal sentence representation remains a bottleneck.

Innovation

This study proposes InferSent, a supervised framework leveraging SNLI data. Key innovations include:

1) Using NLI's semantic reasoning for representation learning.

2) Employing BiLSTM-Max architecture for efficient encoding.

3) Extracting semantic relations via concatenation, element-wise product, and absolute difference.

Methodology

  • �� Train on SNLI dataset with 570k sentence pairs labeled for entailment, contradiction, and neutral relations.
  • �� Use BiLSTM-Max architecture with max-pooling to generate fixed-length sentence vectors.
  • �� Apply three matching methods (concatenation, element-wise product, absolute difference) to extract semantic relations.
  • �� Utilize a multi-layer perceptron classifier for NLI task training.

Experiments

Experiments span 12 transfer tasks, including sentiment analysis (MR, CR), semantic similarity (STS14), and paraphrase detection (MRPC). SentEval tool automates evaluation, comparing against SkipThought and other baselines. Ablation studies validate architectural choices.

Results

BiLSTM-Max achieves superior performance, with a Pearson correlation of 0.68 on STS14 and faster training (one day vs. one month for SkipThought). Results highlight its robustness across diverse tasks.

Applications

Applicable to sentiment analysis, question answering, and semantic similarity tasks, particularly for scenarios requiring efficient universal sentence representation generation.

Limitations & Outlook

Relies on labeled datasets, limiting scalability to low-resource languages; potential overfitting to specific tasks; unexplored performance on non-English datasets.

Plain Language Accessible to non-experts

Imagine organizing books on a shelf. Unsupervised methods sort by color, quick but missing content. This method reads the book's summary (premise and hypothesis) to categorize by theme, creating more meaningful organization.

ELI14 Explained like you're 14

Think of playing a puzzle game! Unsupervised methods randomly connect pieces, forming vague patterns. This method uses hints (premise and hypothesis) to quickly assemble the full picture—faster and more accurate!

Glossary

SNLI dataset

A dataset with 570k sentence pairs labeled for entailment, contradiction, and neutral relations.

Used for supervised training of sentence representations.

BiLSTM-Max

A bidirectional LSTM architecture with max-pooling to generate fixed-length sentence vectors.

Serves as the core sentence encoder.

Transfer learning

Applying knowledge from one task to improve performance on another.

Evaluates sentence representation generality.

Max-pooling

Selecting the maximum value across dimensions of hidden states to form fixed-length vectors.

Used for sentence representation generation.

SentEval tool

An evaluation framework for sentence representations across multiple transfer tasks.

Automates experimental evaluation.

Open Questions Unanswered questions from this research

  • 1 How to scale to low-resource languages?
  • 2 How to combine unsupervised methods for better generalization?

Applications

Immediate Applications

Sentiment Analysis

Useful for movie reviews, product feedback classification.

Question Answering

Improves sentence matching accuracy in QA systems.

Long-term Vision

Multilingual Expansion

Develop universal sentence representation models for global applications.

Abstract

Many modern NLP systems rely on word embeddings, previously trained in an unsupervised manner on large corpora, as base features. Efforts to obtain embeddings for larger chunks of text, such as sentences, have however not been so successful. Several attempts at learning unsupervised representations of sentences have not reached satisfactory enough performance to be widely adopted. In this paper, we show how universal sentence representations trained using the supervised data of the Stanford Natural Language Inference datasets can consistently outperform unsupervised methods like SkipThought vectors on a wide range of transfer tasks. Much like how computer vision uses ImageNet to obtain features, which can then be transferred to other tasks, our work tends to indicate the suitability of natural language inference for transfer learning to other NLP tasks. Our encoder is publicly available.

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