Test-time Alignment of Diffusion Models without Reward Over-optimization
- URL: http://arxiv.org/abs/2501.05803v2
- Date: Mon, 10 Feb 2025 08:16:42 GMT
- Title: Test-time Alignment of Diffusion Models without Reward Over-optimization
- Authors: Sunwoo Kim, Minkyu Kim, Dongmin Park,
- Abstract summary: Diffusion models excel in generative tasks, but aligning them with specific objectives remains challenging.
We propose a training-free, test-time method based on Sequential Monte Carlo (SMC) to sample from the reward-aligned target distribution.
We demonstrate its effectiveness in single-reward optimization, multi-objective scenarios, and online black-box optimization.
- Score: 8.981605934618349
- License:
- Abstract: Diffusion models excel in generative tasks, but aligning them with specific objectives while maintaining their versatility remains challenging. Existing fine-tuning methods often suffer from reward over-optimization, while approximate guidance approaches fail to optimize target rewards effectively. Addressing these limitations, we propose a training-free, test-time method based on Sequential Monte Carlo (SMC) to sample from the reward-aligned target distribution. Our approach, tailored for diffusion sampling and incorporating tempering techniques, achieves comparable or superior target rewards to fine-tuning methods while preserving diversity and cross-reward generalization. We demonstrate its effectiveness in single-reward optimization, multi-objective scenarios, and online black-box optimization. This work offers a robust solution for aligning diffusion models with diverse downstream objectives without compromising their general capabilities. Code is available at https://github.com/krafton-ai/DAS.
Related papers
- DiOpt: Self-supervised Diffusion for Constrained Optimization [46.75288477458697]
DiOpt is a novel diffusion paradigm that systematically learns near-optimal feasible solution distributions through iterative self-training.
To our knowledge, DiOpt represents the first successful integration of self-supervised diffusion with hard constraint satisfaction.
arXiv Detail & Related papers (2025-02-14T17:43:08Z) - Few-shot Steerable Alignment: Adapting Rewards and LLM Policies with Neural Processes [50.544186914115045]
Large language models (LLMs) are increasingly embedded in everyday applications.
Ensuring their alignment with the diverse preferences of individual users has become a critical challenge.
We present a novel framework for few-shot steerable alignment.
arXiv Detail & Related papers (2024-12-18T16:14:59Z) - ParetoFlow: Guided Flows in Multi-Objective Optimization [12.358524770639136]
In offline multi-objective optimization (MOO), we leverage an offline dataset of designs their associated labels to simultaneously multiple objectives.
Recent iteration mainly employ evolutionary and Bayesian optimization, with limited attention given to the generative capabilities inherent in data.
Our method achieves state-of-the-art performance across various tasks.
arXiv Detail & Related papers (2024-12-04T21:14:18Z) - Aligning Few-Step Diffusion Models with Dense Reward Difference Learning [81.85515625591884]
Stepwise Diffusion Policy Optimization (SDPO) is an alignment method tailored for few-step diffusion models.
SDPO incorporates dense reward feedback at every intermediate step to ensure consistent alignment across all denoising steps.
SDPO consistently outperforms prior methods in reward-based alignment across diverse step configurations.
arXiv Detail & Related papers (2024-11-18T16:57:41Z) - Decoding-Time Language Model Alignment with Multiple Objectives [116.42095026960598]
Existing methods primarily focus on optimizing LMs for a single reward function, limiting their adaptability to varied objectives.
Here, we propose $textbfmulti-objective decoding (MOD)$, a decoding-time algorithm that outputs the next token from a linear combination of predictions.
We show why existing approaches can be sub-optimal even in natural settings and obtain optimality guarantees for our method.
arXiv Detail & Related papers (2024-06-27T02:46:30Z) - Covariance-Adaptive Sequential Black-box Optimization for Diffusion Targeted Generation [60.41803046775034]
We show how to perform user-preferred targeted generation via diffusion models with only black-box target scores of users.
Experiments on both numerical test problems and target-guided 3D-molecule generation tasks show the superior performance of our method in achieving better target scores.
arXiv Detail & Related papers (2024-06-02T17:26:27Z) - Bridging Model-Based Optimization and Generative Modeling via Conservative Fine-Tuning of Diffusion Models [54.132297393662654]
We introduce a hybrid method that fine-tunes cutting-edge diffusion models by optimizing reward models through RL.
We demonstrate the capability of our approach to outperform the best designs in offline data, leveraging the extrapolation capabilities of reward models.
arXiv Detail & Related papers (2024-05-30T03:57:29Z) - Diffusion Models as Constrained Samplers for Optimization with Unknown Constraints [42.47298301874283]
We propose to perform optimization within the data manifold using diffusion models.
Depending on the differentiability of the objective function, we propose two different sampling methods.
Our method achieves better or comparable performance with previous state-of-the-art baselines.
arXiv Detail & Related papers (2024-02-28T03:09:12Z) - Diffusion-ES: Gradient-free Planning with Diffusion for Autonomous Driving and Zero-Shot Instruction Following [21.81411085058986]
Reward-gradient guided denoising generates trajectories that maximize both a differentiable reward function and the likelihood under the data distribution captured by a diffusion model.
We propose DiffusionES, a method that combines gradient-free optimization with trajectory denoising.
We show that DiffusionES achieves state-of-the-art performance on nuPlan, an established closed-loop planning benchmark for autonomous driving.
arXiv Detail & Related papers (2024-02-09T17:18:33Z) - Protein Design with Guided Discrete Diffusion [67.06148688398677]
A popular approach to protein design is to combine a generative model with a discriminative model for conditional sampling.
We propose diffusioN Optimized Sampling (NOS), a guidance method for discrete diffusion models.
NOS makes it possible to perform design directly in sequence space, circumventing significant limitations of structure-based methods.
arXiv Detail & Related papers (2023-05-31T16:31:24Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.