Understanding CNNs, RNNs, and LSTMs for Sentiment Analysis
As my research continues, it's becoming all the more apparent just how vital Convolutional Neural Networks (CNNs), Recurrent Neural Networks (RNNs), and Long Short-Term Memory networks (LSTMs) are, within the context of my project. Each offer unique strengths that make them particularly useful for natural language processing tasks like sentiment analysis. Below is a breakdown what each of these models is and why they are important for this project.
Convolutional Neural Networks (CNNs)
CNNs are a type of deep learning model initially designed for image processing. They excel at recognising patterns and features in data through the use of convolutional layers that apply filters to the input data. There are several reasons why CNNs are useful for sentiment analysis, including:
- Local Feature Detection: CNNs are adept at identifying local patterns in text, such as the presence of specific words or phrases that can indicate sentiment. This capability is crucial for understanding the context of social media posts where key sentiment indicators might be present (Kim, 2014).
- Efficiency: CNNs can process data efficiently, making them suitable for real-time sentiment analysis where speed is important.
Recurrent Neural Networks (RNNs)
RNNs are designed to handle sequential data by maintaining a 'memory' of previous inputs. This makes them ideal for tasks where the order of the data matters, such as language modeling and time series prediction. RNNs possess 2 key attributes which make them invaluable for sentiment analysis tasks:
- Sequential Data Handling: RNNs can capture dependencies and context over a sequence of words, which is essential for understanding the sentiment of entire sentences or paragraphs.
- Context Awareness: By remembering previous inputs, RNNs can understand how earlier words in a sentence influence the sentiment of later words (Mikolov et al., 2010).
- Long-Term Dependency Learning: LSTMs excel at capturing long-term dependencies in text, which is particularly useful for understanding complex sentences with multiple clauses and context-specific meanings (Chandra Mouli Venkata Srinivas et al, 2021).
- Handling Nuances: Given their ability to maintain and use information over extended sequences, LSTMs are excellent at detecting nuances such as sarcasm and irony, which are common in social media language.
Regarding the sentiment analysis tool, leveraging the strengths of CNNs, RNNs, and LSTMs will be key to developing a robust system. CNNs will help in quickly identifying key phrases and words that indicate sentiment, providing a preliminary analysis layer. RNNs will ensure that the sequence of words is taken into account, maintaining context over short to medium-length sentences. And LSTMs will handle more complex and longer sentences, capturing long-term dependencies and nuanced expressions that might be missed by simpler models.
By combining these models, the sentiment analysis tool will be capable of accurately interpreting the varied and nuanced language found in social media posts, providing reliable sentiment categorisation and insights.
References:
- Chandra Mouli Venkata Srinivas, A., Satyanarayana, C., Divakar, C., & Phani Sirisha, K. (2021) Sentiment Analysis using Neural Network and LSTM. Available at https://www.researchgate.net/publication/349628900_Sentiment_Analysis_using_Neural_Network_and_LSTM (Accessed: 1 July 2024)
- Kim, Y. (2014) Convolutional Neural Networks for Sentence Classification. Proceedings of the 2014 Conference on Empirical Methods in Natural Language Processing (EMNLP). Available at https://arxiv.org/abs/1408.5882 (Accessed: 2 June 2024)
- Mikolov, T., Karafiat, M., Burget, L., Cernocky, J., & Khudanpur, S. (2010) Recurrent neural network based language model. Available at https://www.researchgate.net/publication/221489926_Recurrent_neural_network_based_language_model (Accessed: 1 July 2024)


