Arabic aspect based sentiment analysis using bidirectional GRU based models

Aspect-based Sentiment analysis (ABSA) accomplishes a fine-grained analysis that defines the aspects of a given document or sentence and the sentiments conveyed regarding each aspect. This level of analysis is the most detailed version that is capable of exploring the nuanced viewpoints of the reviews. Most of the research available in ABSA focuses on English language with very few work available on Arabic. Most previous work in Arabic has been based on regular methods of machine learning that mainly depends on a group of rare resources and tools for analyzing and processing Arabic content such as lexicons, but the lack of those resources presents another challenge. To overcome these obstacles, Deep Learning (DL)-based methods are proposed using two models based on Gated Recurrent Units (GRU) neural networks for ABSA. The first one is a DL model that takes advantage of the representations on both words and characters via the combination of bidirectional GRU, Convolutional neural network (CNN), and Conditional Random Field (CRF) which makes up (BGRU-CNN-CRF) model to extract the main opinionated aspects (OTE). The second is an interactive attention network based on bidirectional GRU (IAN-BGRU) to identify sentiment polarity toward extracted aspects. We evaluated our models using the benchmarked Arabic hotel reviews dataset. The results indicate that the proposed methods are better than baseline research on both tasks having 38.5% enhancement in F1-score for opinion target extraction (T2) and 7.5% in accuracy for aspect-based sentiment polarity classification (T3). Obtaining F1 score of 69.44% for T2, and accuracy of 83.98% for T3.