toplogo
Kirjaudu sisään

Implicit Regularization Effects in Multi-Task Learning and Fine-Tuning of Overparameterized Neural Networks


Keskeiset käsitteet
The author explores implicit regularization effects in multi-task learning and fine-tuning, highlighting biases towards feature sharing and sparse task-specific feature learning. The study uncovers a novel nested feature selection regime that enhances performance through sparsity.
Tiivistelmä

The study delves into the inductive biases of multi-task learning (MTL) and pretraining with subsequent fine-tuning (PT+FT) in neural networks. It reveals how these strategies incentivize feature reuse and sparse task-specific feature learning. The research identifies a unique nested feature selection regime that promotes sparsity within features inherited from pretraining, leading to improved performance. By conducting experiments with linear and ReLU networks, the study validates theoretical predictions and provides practical insights for optimizing training strategies.

Key points:

  • Investigates implicit regularization effects in MTL and PT+FT.
  • Identifies biases towards feature sharing and sparse task-specific features.
  • Introduces a novel nested feature selection regime enhancing network performance.
  • Validates findings through experiments with linear and ReLU networks.
edit_icon

Mukauta tiivistelmää

edit_icon

Kirjoita tekoälyn avulla

edit_icon

Luo viitteet

translate_icon

Käännä lähde

visual_icon

Luo miellekartta

visit_icon

Siirry lähteeseen

Tilastot
In MTL, a solution minimizes an ℓ1,2 penalty incentivizing group sparsity on the learned linear map β. For PT+FT, there is a hybrid of "rich" and "lazy" learning dynamics due to suitable parameter scalings. The PT+FT penalty encourages reusing features from the auxiliary task based on their weights.
Lainaukset
"In this work we characterize the inductive biases of MTL and PT+FT in terms of implicit regularization." "Our findings shed light on the impact of auxiliary task learning and suggest ways to leverage it more effectively."

Syvällisempiä Kysymyksiä

How can the nested feature selection regime be practically implemented in deep neural networks

The nested feature selection regime can be practically implemented in deep neural networks by adjusting the weights of the network following pretraining. This adjustment involves rescaling the weights by a factor less than 1, which pushes the network into the nested feature selection regime. By doing so, the network is biased towards extracting a sparse subset of features learned during pretraining. This bias towards sparsity in task-specific features can be beneficial for tasks where only a small subset of features are relevant or when there is limited data available for fine-tuning. To implement this in practice, one would need to experiment with different rescaling values following pretraining and observe how it affects performance on complex tasks. By identifying an optimal rescaling value that induces the desired sparsity bias without compromising overall performance, practitioners can effectively leverage the benefits of the nested feature selection regime.

What are the implications of biases towards feature sharing for real-world applications beyond image classification tasks

Biases towards feature sharing have significant implications for real-world applications beyond image classification tasks. In various domains such as natural language processing, speech recognition, and reinforcement learning, leveraging shared representations across multiple tasks can lead to improved generalization and sample efficiency. For example: In natural language processing (NLP), models trained on diverse auxiliary tasks like text generation or sentiment analysis before fine-tuning on specific NLP tasks show enhanced performance due to shared representation learning. In speech recognition systems, incorporating multi-task learning with shared layers allows models to capture common patterns across different spoken languages or dialects more effectively. In reinforcement learning scenarios, using auxiliary tasks related to exploration strategies or reward prediction alongside main RL objectives can help agents learn robust policies faster. By understanding and harnessing biases towards feature sharing through multi-task learning and finetuning approaches in these domains, practitioners can develop more efficient and effective AI systems that generalize well across diverse sets of related tasks.

How might different rescaling values affect the performance of PT+FT on complex tasks compared to simple synthetic setups

Different rescaling values following pretraining can have varying effects on PT+FT performance on complex tasks compared to simple synthetic setups: Effectiveness: Higher rescaling values may lead to better generalization initially but could hinder adaptability during fine-tuning if they push networks out of useful regimes like nested feature selection. Sparsity Bias: Lower rescaling values are likely to enhance sparsity bias within task-specific features learned during pretraining but might require careful tuning based on task complexity. Task-Specific Learning: Optimal rescaling values may vary depending on whether main task features overlap with auxiliary task features; finding a balance between reusing informative features from pretraining while adapting specifically for new task requirements is crucial. Overall, exploring how different rescaling strategies impact PT+FT performance in complex settings provides insights into optimizing transfer learning processes for real-world applications where datasets are large and diverse.
0
star