# Generalization Performance of Transfer Learning: Overparameterized and Underparameterized Regimes

arXiv: https://arxiv.org/abs/2306.04901 · HTML: https://mlsanity.com/paper/2306.04901/

## Key facts

- Cited by 4 papers in the map (data through 14 Oct 2026).
- Builds on 20 of its 28 references that are in the map.
- First posted on arXiv 8 Jun 2023.

## Builds on (most cited first, 20 of 20)

- [Fine-Grained Analysis of Optimization and Generalization for Overparameterized Two-Layer Neural Networks](https://mlsanity.com/paper/1901.08584/) (2019)
- [Benign Overfitting in Linear Regression](https://mlsanity.com/paper/1906.11300/) (2019)
- [Surprises in High-Dimensional Ridgeless Least Squares Interpolation](https://mlsanity.com/paper/1903.08560/) (2019)
- [The generalization error of random features regression: Precise asymptotics and double descent curve](https://mlsanity.com/paper/1908.05355/) (2019)
- [Two models of double descent for weak features](https://mlsanity.com/paper/1903.07571/) (2019)
- [To understand deep learning we need to understand kernel learning](https://mlsanity.com/paper/1802.01396/) (2018)
- [On the Theory of Transfer Learning: The Importance of Task Diversity](https://mlsanity.com/paper/2006.11650/) (2020)
- [Harmless interpolation of noisy data in regression](https://mlsanity.com/paper/1903.09139/) (2019)
- [Transfer Learning for High-dimensional Linear Regression: Prediction, Estimation, and Minimax Optimality](https://mlsanity.com/paper/2006.10593/) (2020)
- [An analytic theory of generalization dynamics and transfer learning in deep linear networks](https://mlsanity.com/paper/1809.10374/) (2018)
- [Transfer Learning under High-dimensional Generalized Linear Models](https://mlsanity.com/paper/2105.14328/) (2021)
- [Probing transfer learning with a model of synthetic correlated datasets](https://mlsanity.com/paper/2106.05418/) (2021)
- [Understanding overfitting peaks in generalization error: Analytical risk curves for l2 and l1 penalized interpolation](https://mlsanity.com/paper/1906.03667/) (2019)
- [Phase Transitions in Transfer Learning for High-Dimensional Perceptrons](https://mlsanity.com/paper/2101.01918/) (2021)
- [Double Double Descent: On Generalization Errors in Transfer Learning between Linear Regression Tasks](https://mlsanity.com/paper/2006.07002/) (2020)
- [On the Generalization Power of Overfitted Two-Layer Neural Tangent Kernel Models](https://mlsanity.com/paper/2103.05243/) (2021)
- [The Dynamics of Gradient Descent for Overparametrized Neural Networks](https://mlsanity.com/paper/2105.06569/) (2021)
- [A Class of Geometric Structures in Transfer Learning: Minimax Bounds and Optimality](https://mlsanity.com/paper/2202.11685/) (2022)
- [On the Generalization Power of the Overfitted Three-Layer Neural Tangent Kernel Model](https://mlsanity.com/paper/2206.02047/) (2022)
- [Theoretical Characterization of the Generalization Performance of Overfitted Meta-Learning](https://mlsanity.com/paper/2304.04312/) (2023)

## Built on by (most cited first, 4 of 4)

- [Transfer Learning for Benign Overfitting in High-Dimensional Linear Regression](https://mlsanity.com/paper/2510.15337/) (2025)
- [HKTGNN: Hierarchical Knowledge Transferable Graph Neural Network-based Supply Chain Risk Assessment](https://mlsanity.com/paper/2311.04244/) (2023)
- [Can We Theoretically Quantify the Impacts of Local Updates on the Generalization Performance of Federated Learning?](https://mlsanity.com/paper/2409.03863/) (2024)
- [Expectation Error Bounds for Transfer Learning in Linear Regression and Linear Neural Networks](https://mlsanity.com/paper/2603.28739/) (2026)

## Abstract (arXiv)

Transfer learning is a useful technique for achieving improved performance and reducing training costs by leveraging the knowledge gained from source tasks and applying it to target tasks. Assessing the effectiveness of transfer learning relies on understanding the similarity between the ground truth of the source and target tasks. In real-world applications, tasks often exhibit partial similarity, where certain aspects are similar while others are different or irrelevant. To investigate the impact of partial similarity on transfer learning performance, we focus on a linear regression model with two distinct sets of features: a common part shared across tasks and a task-specific part. Our study explores various types of transfer learning, encompassing two options for parameter transfer. By establishing a theoretical characterization on the error of the learned model, we compare these transfer learning options, particularly examining how generalization performance changes with the number of features/parameters in both underparameterized and overparameterized regimes. Furthermore, we provide practical guidelines for determining the number of features in the common and task-specific parts for improved generalization performance. For example, when the total number of features in the source task's learning model is fixed, we show that it is more advantageous to allocate a greater number of redundant features to the task-specific part rather than the common part. Moreover, in specific scenarios, particularly those characterized by high noise levels and small true parameters, sacrificing certain true features in the common part in favor of employing more redundant features in the task-specific part can yield notable benefits.
