Advancements in Text Summarization: Enhancing Information Processing with AI

Dr Padma Murali
6 min readApr 13, 2023

Text summarization is an important application of Natural Language Processing. It is the process of automatically generating a shorter version of a given text while preserving its essential information. This technology has numerous applications in today’s world, including news article summarization, social media post summarization, and summarization of research papers, to name a few.

Suppose you are a busy professional who wants to keep up with the latest developments in your industry. You subscribe to multiple newsletters, read research papers, and follow social media accounts related to your field. However, you find it difficult to keep up with all the information overload, and it is impossible to read everything in detail. This is where text summarization comes in handy. You can use text summarization algorithms to generate summaries.

courtesy: scrapehero.com

There are two main approaches to text summarization: extractive and abstractive summarization. Extractive summarization involves selecting a subset of sentences from the original text and combining them to form a summary. Abstractive summarization, on the other hand, involves generating new sentences that capture the essence of the original text. Both approaches have their strengths and weaknesses, and the choice of approach depends on the specific task and the available resources.

Extractive Summarization:

Extractive summarization involves identifying the most important sentences in the original text and combining them to form a summary. This can be done using a variety of techniques, such as:

  1. Frequency-based methods: These methods rank the sentences in the original text based on their frequency of occurrence and select the top-ranked sentences for the summary. The assumption is that the most important information is repeated several times in the text.
  2. Centrality-based methods: These methods identify the most central sentences in the original text based on their position in the text and their similarity to other sentences. The idea is that the most important sentences are those that are closely related to other sentences in the text.
  3. Graph-based methods: These methods represent the original text as a graph of nodes and edges, where nodes represent sentences and edges represent the relationship between sentences. The most important sentences are then identified based on their position in the graph and their centrality.
  4. Machine learning-based methods: These methods use machine learning algorithms to learn the most important features of the original text and identify the most important sentences. They can be trained on a large corpus of annotated data to improve their performance.

Abstractive Summarization:

Abstractive summarization involves generating new sentences that capture the essence of the original text. This is a more challenging task than extractive summarization, as it requires the model to understand the meaning of the text and generate new sentences that convey the same meaning in a more concise way. Some of the techniques used in abstractive summarization include:

  1. Sequence-to-sequence models: These models use a neural network to encode the original text into a fixed-length vector and then decode the vector into a summary. They can be trained on a large corpus of annotated data to learn the most important features of the original text and generate high-quality summaries.
  2. Attention mechanisms: These mechanisms allow the model to focus on the most important parts of the original text while generating the summary. They can improve the quality of the summary by ensuring that the most important information is included.
  3. Transformer-based models: These models use a self-attention mechanism that allows the model to attend to different parts of the input sequence and generate more coherent and accurate summaries. They have achieved state-of-the-art results in a variety of NLP tasks, including text summarization

There are several algorithms used in text summarization, and the choice of algorithm depends on the specific task and the available resources.

One of the most popular algorithms used for text summarization is Textrank, an unsupervised algorithm based on Pagerank, which is used by Google to rank web pages. Textrank works by treating sentences as nodes in a graph and uses the relationships between them to identify the most important sentences in the text. For instance, let us consider a news article about a recent breakthrough in cancer treatment. TextRank can be used to identify the most important sentences in the article, such as the breakthrough drug name, the medical trial details, and the potential impact on cancer patients.

Latent Semantic Analysis (LSA) is another statistical algorithm used for text summarization. LSA works by representing the text as a matrix of word frequency counts and identifying patterns in the relationships between words. For example, suppose we have a research paper on climate change. LSA can be used to identify the most important topics discussed in the paper, such as global warming, greenhouse gases, and renewable energy.

Non-negative Matrix Factorization (NMF) is another matrix factorization algorithm that can be used for text summarization. NMF works by decomposing a matrix into two non-negative matrices, and it can be used to identify the most important topics in the text and select the most important sentences related to those topics for the summary. For instance, consider a social media post about a new product launch. NMF can be used to identify the most important features of the product, such as its price, functionality, and availability.

Deep learning models such as convolutional neural networks (CNNs) and recurrent neural networks (RNNs) can also be used for text summarization. These models can be trained on large amounts of annotated data to learn the most important features of the text and generate high-quality summaries. For example, let us consider a news article about a recent political development. A deep learning model can be trained on a large corpus of news articles to learn the most important features of political news, such as the key players involved, the impact on the country, and public reactions.

Finally, transformer-based models such as BERT and GPT-2 have gained significant popularity for text summarization due to their ability to learn from large amounts of annotated data and generate high-quality summaries. For instance, consider a research paper on artificial intelligence ethics. A transformer-based model can be used to identify the most important ethical issues discussed in the paper, such as privacy, bias, and fairness.

There are several large language model algorithms as well that can be used for text summarization. Some of the most popular ones include:

  1. BERT (Bidirectional Encoder Representations from Transformers): BERT is a powerful transformer-based language model that has been used for a wide range of natural language processing tasks, including text summarization. BERT can be fine-tuned for text summarization by adding a summarization layer on top of its pre-trained encoder.
  2. GPT-3 (Generative Pre-trained Transformer 3): GPT-3 is a state-of-the-art language model that has achieved impressive results in various natural language processing tasks. It can be used for text summarization by fine-tuning the model with a summarization task-specific objective.
  3. T5 (Text-to-Text Transfer Transformer): T5 is another powerful transformer-based language model that can be used for text summarization. It has been pre-trained on a wide range of natural language tasks and can be fine-tuned for summarization.
  4. Pegasus: Pegasus is a transformer-based model specifically designed for text summarization. It uses a pre-training approach called unsupervised pre-training with exemplars (UPE) that allows it to achieve state-of-the-art results in summarization tasks.
  5. MASS (Masked Sequence-to-Sequence Pre-training): MASS is another transformer-based model that can be used for text summarization. It uses a masked sequence-to-sequence pre-training approach that enables it to handle long sequences of text.

In conclusion, text summarization algorithms have numerous applications in today’s world, and advancements in AI have made it possible to generate high-quality summaries that capture the essential information from the original text. Whether it is news article summarization, social media post summarization, or summarization of research papers, text summarization algorithms play a critical role in enhancing our ability to understand and process information more efficiently.

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Dr Padma Murali

Senior AI Research Scientist with 19 years experience working in AI/ML,NLP, Responsible AI & Large Language Models