Constraint-Aware Generative Auto-bidding via Pareto-Prioritized Regret Optimization

arXiv:2602.08261 · cs.LG, cs.GT · Submitted 2026-08-17 · Read on arXiv

Listen

Radio episode about this paper

Transcript

Introduction to the show: ident: AI Radio. Generated commentary on the latest Artificial Intelligence papers.

Tom: Next we'll be talking about the paper "PRO-Bid: Pareto-Prioritized Regret Optimization for Constraint-Aware Generative Auto-Bidding".

Jane: The paper was written by Binglin Wu, Yingyi Zhang, Xianneng Li, Ruyue Deng, Chuan Yue et al. from Dalian University of Technology and City University of Hong Kong and Alibaba International Digital Commerce Group.

Tom: Stay tuned as we take you through the paper and discuss its implications.

Title: Tom: We are starting our show today with a real heavyweight in the world of automated advertising, a paper titled PRO-Bid: Pareto-Prioritized Regret Optimization for Constraint-Aware Generative Auto-Bidding.

Jane: That title is quite a mouthful, Tom.

Tom: It definitely is, but it tells you exactly what's under the hood.

Jane: I think it's helpful to realize that the authors, including Binglin Wu and a team from Dalian University of Technology and Alibaba, are tackling a very specific headache.

Lu: They are looking at how to make AI spend money in auctions without breaking the rules the advertiser sets.

Tom: Does that mean they're focusing on the balance between spending and winning, Jane?

Jane: Exactly, because in advertising, you can't just spend as much as you want; you have to hit a specific target, like a certain cost per action.

Meng: Since this comes from researchers working with Alibaba, I'm assuming they've dealt with the massive scale of real-world transactions.

Tom: You're right, Meng, because this isn't just a theoretical math exercise.

Lu: The "Pareto" part of the title suggests they're looking for that perfect equilibrium where you maximize value without overstepping your budget.

Jane: And "Regret Optimization" sounds like the AI is learning from its own missed opportunities.

Meng: I'm curious to see if this actually works when the data gets messy, though.

Lalam: It's a fascinating attempt to bring more harmony to how digital resources are distributed across the internet.

Tom: We'll see if that harmony holds up when we look at the actual mechanics of the model in the next segment.

Summary: Tom: We've touched on the name, but now let's get into the actual mechanics of PRO-Bid: Pareto-Prioritized Regret Optimization for Constraint-Aware Generative Auto-Bidding.

Jane: To understand this, you have to realize that current AI models are actually quite bad at keeping track of a remaining budget.

Tom: They call that "state aliasing," which basically means the AI sees the goal but completely forgets how much cash it has left to get there.

Jane: It's like trying to finish a grocery list but forgetting how much money is left in your wallet halfway through the aisle.

Lu: And the paper points out that these models also tend to just mimic the average behavior of whatever data they're given.

Tom: So they end up being mediocre because they're copying the mediocre decisions from the past?

Lu: That's a great way to put it, Tom, and that's why they introduced the CDPR mechanism.

Meng: How does splitting the data help with that mediocrity problem?

Lu: CDPR essentially splits the AI's focus into two separate streams, one for the value it's getting and one for the cost it's incurring.

Jane: It gives the AI a much clearer picture of its boundaries.

Tom: But they didn't stop there, because they also added something called CRO to push the model to be better than the history it's studying.

Meng: Is that the part where the AI "imagines" better moves?

Tom: Yes, it uses a predictor to look at "counterfactual" actions, which are just "what if" scenarios that would have worked better.

Jane: It's like looking back at a choice and saying, "If I had taken this other path, I would have been much more efficient."

Lu: By treating those better "what if" scenarios as the new goal, the AI stops being average and starts aiming for the top.

Lalam: It's a shift from passive observation to active, intelligent improvement.

Tom: We'll see just how much that improvement actually matters when we look at the hard numbers in a moment.

Improvements: Tom: We've seen how the math works in PRO-Bid: Pareto-Prioritized Regret Optimization for Constraint-Aware Generative Auto-Bidding, but let's talk about the actual proof.

Jane: The results from their tests on the AuctionNet dataset are really impressive.

Tom: I was looking at the AliExpress A/B test results, and they're even more striking.

Jane: They saw a seven point zero seven percent increase in GMV and a nearly eight percent jump in ROI.

Meng: But did they achieve those higher numbers by just being more aggressive and breaking the budget constraints?

Jane: That's the best part, Meng, because they actually improved constraint satisfaction by over six percent.

Tom: They're making more money while actually being more disciplined with the rules.

Lu: I was particularly struck by how they handled the "noise" in the data.

Meng: You mean the part where they added synthetic errors to see if the model would collapse?

Lu: Exactly, and while the standard models fell apart, PRO-Bid stayed incredibly robust.

Tom: It seems like their Pareto-prioritized filtering really helps them ignore the garbage data.

Jane: It's like a filter that only lets the high-quality, efficient examples through to the training stage.

Lu: And they even managed to exceed the best performance found in the original historical logs.

Tom: They aren't just copying the best people from the past; they're actually finding ways to be even better.

Lalam: This kind of reliability is what allows digital markets to function with much higher levels of trust and efficiency.

Tom: It really is a massive step forward for automated systems.

Conclusion: Tom: We've covered everything from the complex title of PRO-Bid: Pareto-Prioritized Regret Optimization for Constraint-Aware Generative Auto-Bidding to those incredible real-world wins.

Jane: It's been such a clear look at how we can move AI from just mimicking humans to actually optimizing for complex goals.

Tom: We've seen how they fixed the "forgetfulness" of budget tracking and how they used "what if" scenarios to beat the average.

Lu: It's a beautiful marriage of regret theory and sequence modeling.

Meng: I'm definitely walking away thinking about how much more stable these bidding systems can become when they can handle noisy, real-world data.

Lalam: And I'm thinking about the broader impact of having AI that understands not just how to grow, but how to grow within sustainable boundaries.

Tom: Well, that's all the time we have for this one.

Jane: Thanks for joining us to talk about PRO-Bid: Pareto-Prioritized Regret Optimization for Constraint-Aware Generative Auto-Bidding.

Tom: We'll be back soon with the next big paper on the arXiv.

Jane: Goodbye for now!

Binglin Wu, Yingyi Zhang, Xianneng Li, Ruyue Deng, Chuan Yue, Weiru Zhang, Xiaoyi Zeng

Dalian University of Technology · City University of Hong Kong · Alibaba International Digital Commerce Group

cs.LG, cs.GT

Submitted: 2026-08-17

Updated: 2026-08-18

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Importance score: 89/100

Key concepts

State Aliasing
State aliasing occurs when an AI model knows its ultimate goal but fails to track the remaining resources or budget needed to achieve that goal. It is like trying to complete a task while forgetting how much money is left in your wallet halfway through the process.
Constraint-Aware Generative Auto-Bidding
This refers to automated bidding systems that are designed with specific, predefined boundaries. The system ensures the AI does not exceed a set target, such as a specific cost per action or total budget limit, while still maximizing value.
Regret Optimization
This mechanism allows the AI to learn from past shortcomings. It evaluates 'what if' scenarios—better alternative choices—and treats these ideal outcomes as the new goal, allowing the system to move beyond merely mimicking average historical behavior.
CDPR Mechanism
The CDPR mechanism divides the AI's focus into two distinct streams. One stream tracks the value being gained from actions, while the other monitors the cost incurred. This separation provides a clearer picture of operational boundaries and helps manage resource allocation.

Terminology

Summary

Summary

This paper introduces PRO-Bid, a constraint-aware generative auto-bidding framework designed to address two fundamental limitations of existing Decision Transformer (DT) approaches in the context of hard ratio constraints in online advertising. The authors state that Auto-bidding systems aim to maximize marketing value while satisfying strict efficiency constraints such as Target Cost-Per-Action (CPA). They identify two critical challenges: "1) standard Return-to-Go conditioning causes state aliasing by neglecting the cost dimension, preventing precise resource pacing; and 2) standard regression forces the policy to mimic average historical behaviors, thereby limiting the capacity to optimize performance toward the constraint boundary."

To address these challenges, the paper proposes two synergistic mechanisms. The first is Constraint-Decoupled Pareto Representation (CDPR), which decomposes global constraints into recursive cost and value contexts to restore resource perception, while reweighting trajectories based on the Pareto frontier to focus on high-efficiency data. Specifically, CDPR introduces a dual-stream context construction that augments the trajectory with both Return-to-Go (Rt) and Cost-to-Go (Ct), defined recursively as Rt = ΣTt′=t rt′ and Ct = ΣTt′=t ct′. This formulation enables the agent to learn an explicit trade-off function that determines the optimal bid parameter based on remaining budget Ct required to acquire value Rt. Additionally, CDPR includes a Pareto-prioritized experience filtering mechanism that assigns sampling probabilities to trajectories based on three quality scores: Efficiency Score (based on Euclidean distance to the Pareto frontier), Compliance Score (penalizing constraint violations), and Richness Score (normalized trajectory length). The final sampling probability is normalized across the dataset.

The second mechanism is Counterfactual Regret Optimization (CRO), which facilitates active improvement by utilizing a global outcome predictor to identify superior counterfactual actions. CRO employs a probabilistic policy with a Gaussian Action Head, modeling the bidding parameter as pitheta(atR≤t, C≤t, s≤t, a<t) = N(mutheta(ht), sigmatheta2(ht)). It introduces a Global Outcome Predictor that shares the transformer backbone and predicts cumulative future outcomes (value and cost). The framework defines a full-episode constraint-aware utility function that integrates historical observed data with predicted future outcomes, applying a penalty-based scoring metric: U(a) = P(rho(a); rhotgt) · R total(a), where P penalizes actions leading to global violations. The optimization is performed via Regret-Weighted Regression (RWR), which generates K counterfactual actions, computes the positive utility gain relative to the baseline policy mean, and converts these gaps into normalized importance weights using a Boltzmann distribution. The final training objective integrates four components: negative log-likelihood for stability, regret-weighted regression for improvement, prediction loss for accuracy, and Shannon entropy regularizer for exploration.

The paper reports extensive experiments on two public benchmarks (AuctionNet and AuctionNet-Sparse) and online A/B tests on the AliExpress advertising system. The results demonstrate that PRO-Bid achieves superior constraint satisfaction and value acquisition compared to state-of-the-art baselines. In offline experiments, PRO-Bid consistently achieves the highest Score across all budget settings (50%, 75%, 100%, 125%, 150%), with improvements ranging from 2.39% to 6.02% over the best baseline. The ablation study shows that removing CDPR causes the most significant degradation in constraint satisfaction, as evidenced by a substantial increase in the Exceed Rate, while removing CRO results in a notable decline in both conversion volume and score, whereas constraint adherence remains relatively stable. The online A/B test results show improvements of +7.07% in GMV, +9.56% in clicks, +7.98% in ROI, and +6.18% in constraint compliance rate compared to the production baseline. The paper concludes that PRO-Bid achieves superior value acquisition while strictly adhering to efficiency constraints, establishing a robust solution for auto-bidding in complex advertising environments.

Improvements for AI systems

Based on the paper, here are the specific improvements I can implement in AI systems, along with the resulting capabilities:


What I will implement:

  • Replace single-dimensional Return-to-Go (RTG) conditioning with a dual-stream context that tracks both remaining value (R t) and remaining allowable cost (C t) as separate, recursively-updated tokens.

  • Add a Pareto-frontier-based trajectory reweighting mechanism that assigns higher sampling probability to trajectories that are non-dominated in the cost-value objective space, with an exponential decay kernel based on distance to the frontier.

What the improved AI system can do:

  • Eliminate state aliasing in constrained tasks: The system can now distinguish between states with identical remaining value but different remaining costs, enabling precise resource pacing.

  • Adapt bidding intensity in real-time: When cost consumption accelerates, the system automatically tightens its action distribution to avoid constraint violations; when cost is underutilized, it becomes more aggressive to maximize value.

  • Filter noisy training data: By prioritizing trajectories near the Pareto frontier, the system becomes robust to suboptimal or contaminated historical logs, maintaining high performance even when up to 40% of training data is noisy.

  • Generalize across varying constraint targets: The system can perceive changes in the efficiency target (e.g., CPA) and adjust its behavior accordingly, showing a clear positive correlation between constraint relaxation and performance.

The improved AI system, based on PRO-Bid, can:

  1. Perceive and respect hard constraints (budget, CPA, ROAS) in real-time, avoiding costly violations.

  2. Actively optimize beyond historical data, converging toward the Pareto-optimal frontier of value and cost.

  3. Remain robust to noisy, sparse, or suboptimal training data through Pareto-prioritized sampling.

  4. Generalize across different constraint targets and budget levels without manual tuning.

  5. Deploy safely in production with strict constraint compliance, as validated by online A/B tests showing simultaneous gains in GMV, clicks, ROI, and constraint satisfaction.

Sources

Related papers