Attention-enhanced BiLSTM for causal sentiment mining in noisy social-media streams
摘要
Short, noisy social-media messages make sentiment analysis particularly challenging: slang, emojis, and misspellings not only reduce predictive accuracy but also obscure why a model outputs a given polarity. This paper introduces a lightweight hybrid model that combines a convolutional block, a bidirectional long short-term memory network (BiLSTM), and a single multi-head self-attention layer with a novel noise-invariant contrastive head (NICH) that normalizes noisy tokens before encoding. The model is trained in two phases (frozen then fine-tuned word embeddings) and evaluated on two contrasting benchmarks: Sentiment140 (1.6M tweets) and IMDb (50k movie reviews). Across both datasets, our approach outperforms classical baselines (logistic regression, support vector machine, random forest) and an Attention-BiLSTM reference model, while remaining competitive with a compact Transformer-based baseline (DistilBERT), achieving 90.63% accuracy and 0.9079