Studying Large Language Model Generalization with Influence Functions

Studying Large Language Model Generalization with Influence Functions

Authors

Roger Grosse, Juhan Bae, Cem Anil, Nelson Elhage, Alex Tamkin, Amirhossein Tajdini, Benoit Steiner, Dustin Li, Esin Durmus, Ethan Perez, Evan Hubinger, Kamilė Lukošiūtė, Karina Nguyen, Nicholas Joseph, Sam McCandlish, Jared Kaplan, Samuel R. Bowman.

Academic Affiliation

University of Toronto and Vector Institute
arXiv preprint arXiv:2308.03296 (2023).

Abstract

The paper explores the application of influence functions to study the generalization behaviors of large language models (LLMs), which traditionally face scalability issues due to the computational demands of inverse-Hessian-vector products (IHVPs). Using an Eigenvalue-corrected Kronecker-Factored Approximate Curvature (EK-FAC) approximation, the paper demonstrates a method to scale influence functions for LLMs up to 52 billion parameters. The approach reduces the computation time significantly while retaining similar accuracy to traditional methods. The study delves into various generalization patterns including sparsity, cross-lingual abilities, and role-playing behaviors, revealing that while LLMs demonstrate sophisticated generalization, there are notable limitations when key phrases are reordered.

Why should you read this paper?

This paper provides a comprehensive look into adapting influence functions for large-scale models, presenting both innovative methodologies and significant findings on how LLMs generalize information, crucial for developers and researchers in AI and machine learning.

Key Points

  • Scalability of Influence Functions: The use of EK-FAC allows the scaling of influence functions to LLMs with billions of parameters, overcoming previous computational limits.
  • Generalization Insights: Examination of generalization patterns reveals that LLMs show increased abstraction and improved abilities in math and programming with larger scale models.
  • Limitations in Generalization: A key limitation identified is the decay of influence when the order of key phrases in the training data is altered.
  • Role-Playing Behavior: The study notes that LLMs’ role-playing capabilities, which are influenced by similar behaviors in the training set, are more a result of mimicry than sophisticated planning.

Broader Context

The research offers valuable insights into the training dynamics of LLMs and their generalization behaviors, contributing to the ongoing discussions on improving model reliability and functionality. This is particularly relevant as AI systems are increasingly being deployed in diverse and critical applications.

Q&A

What are influence functions and why are they important for LLMs?
Influence functions help determine how changes in the training data affect the model’s outputs, providing insights into the model’s learning behavior and decision-making processes.

How does the EK-FAC approximation aid in scaling influence functions for large models?
EK-FAC simplifies the computation of the inverse-Hessian-vector product, reducing computational demands and enabling the application of influence functions to very large models.

What does the decay of influence when reordering key phrases imply about LLM generalization?
This limitation suggests that while LLMs can generalize from training data to new contexts, their understanding is somewhat rigid and dependent on specific patterns or sequences in the data.

Deep Dive

The concept of influence functions in LLMs is based on understanding how specific pieces of training data affect the model’s output. This paper uses a novel approximation method (EK-FAC) that allows researchers to efficiently compute these influence functions even for models with tens of billions of parameters, which was previously not feasible due to computational constraints.

Future Scenarios and Predictions

Looking ahead, the paper’s methodologies could lead to more robust and interpretable LLMs by allowing for more detailed analyses of how training data influences model behavior. This could lead to better designed training processes that mitigate unwanted biases or erroneous behaviors in AI systems.

Inspiration Sparks

Imagine applying the insights from this study to design training sets that enhance LLMs’ ability to generalize across languages or solve complex problems without direct training on those tasks. How could we structure such datasets and what kind of preprocessing would maximize beneficial influences?

You can read full research article here.

Grosse, Roger, Juhan Bae, Cem Anil, Nelson Elhage, Alex Tamkin, Amirhossein Tajdini, Benoit Steiner et al. “Studying large language model generalization with influence functions.” arXiv preprint arXiv:2308.03296 (2023).