Zero-shot Audio Topic Retrieval using Large Language Models

Core Concepts

Large language models can be effectively used for zero-shot reranking to significantly improve audio topic retrieval performance without requiring any task-specific in-domain training data.

Abstract

This paper presents a two-stage audio topic retrieval system that leverages the strengths of pre-trained language models and transfer learning.
In the first stage, audio files are represented by vector embeddings to enable rapid retrieval from large archives. Three different text sources are examined for extracting these embeddings: automatic speech recognition (ASR) transcriptions, automatic summaries (AutoSum) of the ASR transcriptions, and human-written synopses.
The results show that the retrieval system built using human-written synopses outperforms the one using ASR transcriptions, with an nDCG@3 of 0.61 compared to 0.47. This performance gap is analyzed using a fact-checking approach, which reveals that synopses contain more than 50% of atomic facts not present in the ASR transcriptions.
To address this, the authors propose using AutoSum, which narrows the performance gap with the Synopsis system, improving the nDCG@3 from 0.47 to 0.52.
In the second stage, zero-shot reranking methods using large language models (LLMs) are investigated to further boost the retrieval performance. Two reranking approaches are examined: listwise reranking (LRL) and pairwise reranking (PRL). The results show that the PRL method with the Flan-T5-3B model achieves comparable performance to the LRL counterpart while being more computationally efficient. Pairwise reranking with AutoSum improves the nDCG@3 to 0.54, representing a 14.9% relative improvement compared to the baseline retrieval with ASR transcriptions.

Stats

Over 9,000 copies of Emma's book were sold worldwide, including in Thailand, Germany, Denmark, Canada, and schools in Mallow and County Cork.
Emma raised over 9,000 copies of her book for the Northern Ireland Council for Orthopedic Development through sales from all over the world.

Quotes

"Emma raised over 9,000 copies of her book for the Northern Ireland Council for Orthopedic Development through sales from all over the world, including Thailand, Germany, Denmark, Canada, and even schools in Mallow and County Cork."
"She is now planning to write a new book of poems."

Key Insights Distilled From

Zero-shot Audio Topic Reranking using Large Language Models

by Mengjie Qian... at arxiv.org 09-11-2024

https://arxiv.org/pdf/2309.07606.pdf

Deeper Inquiries

How can the proposed zero-shot reranking methods be extended to other multimedia retrieval tasks beyond audio topic retrieval?

The proposed zero-shot reranking methods can be extended to various multimedia retrieval tasks by leveraging the inherent flexibility of large language models (LLMs) and their ability to process diverse input types. For instance, in image retrieval, the same zero-shot reranking framework can be applied by using image captions or descriptions as queries, allowing the model to rank images based on their relevance to the textual input. Similarly, in video retrieval, the methods can utilize video metadata, transcripts, or even visual features extracted from the video frames to perform reranking.
Moreover, the zero-shot approach can be adapted to tasks such as sentiment analysis in multimedia content, where the model can evaluate the emotional tone of video clips or audio segments based on user-defined queries. By employing embeddings generated from various modalities (text, audio, and visual), the reranking methods can effectively assess the relevance of multimedia content across different domains. This adaptability not only enhances the retrieval performance but also reduces the dependency on task-specific training data, making it a versatile solution for a wide range of multimedia retrieval applications.

What are the potential limitations of the fact-checking approach used in the analysis, and how could it be improved to provide a more comprehensive understanding of the information consistency across different text sources?

The fact-checking approach employed in the analysis, while effective in evaluating information consistency, has several limitations. One significant limitation is the reliance on the quality and comprehensiveness of the atomic facts generated from the text sources. If the initial decomposition of facts is incomplete or inaccurate, it can lead to misleading evaluations of consistency. Additionally, the model's ability to assess the truthfulness of facts is contingent on the knowledge it has been trained on, which may not encompass all relevant contexts or nuances present in the multimedia content.
To improve this approach, a multi-faceted evaluation framework could be developed that incorporates additional layers of verification. For instance, integrating external knowledge bases or databases could enhance the model's ability to cross-reference facts against a broader context. Furthermore, employing a human-in-the-loop system where domain experts review and validate the generated facts could significantly increase the reliability of the fact-checking process. Lastly, expanding the range of prompts used for fact evaluation to include contextual questions could provide deeper insights into the relationships between different text sources, leading to a more nuanced understanding of information consistency.

Given the performance gap between the systems using ASR transcriptions and human-written synopses, what other techniques could be explored to bridge this gap without relying on the availability of high-quality manual annotations?

To bridge the performance gap between systems using ASR transcriptions and human-written synopses, several techniques can be explored that do not depend on high-quality manual annotations. One promising approach is the use of semi-supervised learning, where a small amount of labeled data (e.g., high-quality synopses) is combined with a larger set of unlabeled ASR transcriptions. This can help the model learn to generate more accurate summaries or embeddings by leveraging the structure and patterns found in the labeled data.
Another technique is the implementation of advanced natural language processing (NLP) methods, such as transformer-based models, to refine ASR outputs. These models can be trained to correct common transcription errors and enhance the coherence and relevance of the generated text. Additionally, employing data augmentation strategies, such as paraphrasing or back-translation, can create variations of ASR transcriptions that mimic the richness of human-written content.
Furthermore, utilizing unsupervised summarization techniques can help distill key information from ASR transcriptions, producing concise summaries that retain essential context. By integrating these methods, it is possible to enhance the quality of ASR outputs and reduce the performance gap with human-written synopses, ultimately improving the overall effectiveness of the retrieval system.