State-space modeling in long sequence processing: a survey on recurrence in the transformer era.
Matteo Tiezzi1, Michele Casoni2, Alessandro Betti3
1IIT, Ist. Italiano di Tecnologia, Genova, 16152, Italy.
Summary
This survey explores recent advancements in recurrent neural networks for processing long sequential data. It highlights new architectures and algorithms that overcome limitations of current technologies, paving the way for more efficient AI.
Area of Science:
- Artificial Intelligence
- Machine Learning
- Deep Learning
Background:
- Learning from sequential data, especially long sequences, is a core AI challenge.
- Traditional methods and Transformers have limitations in capturing long-term dependencies.
- Recurrent Neural Networks (RNNs) are experiencing a resurgence due to new State-Space Models and large-context Transformers.
Purpose of the Study:
- To provide an in-depth summary of recent recurrent model-based approaches for sequential data processing.
- To offer a taxonomy of current trends in recurrent architectures and algorithms.
- To guide researchers in the field of sequential data processing.
Main Methods:
- Survey of recent literature on recurrent models for sequential data.
- Analysis of architectural and algorithmic innovations.
- Discussion of emerging trends and their implications.
Main Results:
- Recurrent computations are key to overcoming limitations of existing technologies like Transformers.
- Deep State-Space Models and large-context Transformers demonstrate the revival of recurrent approaches.
- Novel recurrent architectures offer improved efficiency for processing long sequences.
Conclusions:
- The field is moving towards more realistic online processing of sequential data.
- There is potential for developing learning algorithms beyond Backpropagation Through Time.
- Future research can focus on local-forward computations for efficient, real-time sequential data processing.
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