Generative advertising in large language model (LLM) responses requires optimizing sponsorship configurations under two strict constraints: the strategic behavior of advertisers and the high cost of stochastic generations. To address this, we propose the Incentive-Aware Multi-Fidelity Mechanism (IAMFM), a unified framework coupling Vickrey-Clarke-Groves (VCG) incentives with Multi-Fidelity Optimization to maximize expected social welfare. We compare two algorithmic instantiations (elimination-based and model-based), revealing their budget-dependent performance trade-offs. Crucially, to make VCG computationally feasible, we introduce Active Counterfactual Optimization, a "warm-start" approach that reuses optimization data for efficient payment calculation. We provide formal guarantees for approximate strategy-proofness and individual rationality, establishing a general approach for incentive-aligned, budget-constrained generative processes. Experiments demonstrate that IAMFM outperforms single-fidelity baselines across diverse budgets.
Figures & tables
Figure 1: Visual Over-Saturation in Generative Advertising (advertisers: Alpha sports jacket and Beta boba). (a) Baseline produces a natural image lacking commercial utility (unbranded cup and jacket). Balanced configurations naturally prioritize a single brand: (b) sharp focus on Alpha logo with a blurred Beta branded cup; (c) prominent Beta logo, pushing Alpha to the periphery. Conversely, extreme parameters (d) cause catastrophic structural collapse, hallucinating an amalgamated “AB” logo onto the boba cup.
Figure 2
Figure 2: Comparison of welfare across all methods. Left: Box plots stratified by token budget summarize performance, showing the median (center line), mean (diamond), interquartile range (box), and outliers (points). All reported statistics include outliers. The IAMFM methods outperform the baselines and reveal a token-budget-dependent shift in the optimal method. Right: Aggregated performance across all budgets. Our proposed multi-fidelity instantiations (IAMFM-MFBO, IAMFM-ASH) show better median performance, while IAMFM-MFBO demonstrates a clear advantage at higher budgets.
Method
Mean Welfare ± Std. Dev.
Low-Budget ( ≤16k tokens)
High-Budget ( ≥32k tokens)
IAMFM-MFBO
186.26 ± 5.02
190.73 ± 5.53
IAMFM-ASH
187.26 ± 6.00
187.43 ± 7.93
UCB Bandit
182.78 ± 4.15
187.04 ± 1.58
Uniform Sampling
184.26 ± 4.62
185.87 ± 2.41
IAMFM-SH
184.42 ± 10.10
185.21 ± 11.68
Table 1: Aggregated performance (mean welfare ± std. dev.) stratified by budget regime. Methods are sorted by High-Budget performance. Bolded are proposed methods.
Budget
IAMFM-MFBO
IAMFM-ASH
IAMFM-SH
UCB Bandit
Uniform Sampling
500
231.25 ± 5.29
233.12 ± 1.97
231.24 ± 3.64
225.41 ± 2.14
228.95 ± 5.45
1,000
232.07 ± 5.86
230.56 ± 5.79
231.96 ± 7.39
229.12 ± 2.87
230.80 ± 5.08
2,000
233.29 ± 7.93
231.99 ± 5.99
233.19 ± 5.40
229.67 ± 4.56
230.56 ± 5.65
4,000
238.24 ± 6.85
231.43 ± 5.20
233.41 ± 5.04
233.14 ± 5.23
232.25 ± 4.85
8,000
240.26 ± 5.92
232.88 ± 5.79
231.48 ± 6.79
235.58 ± 2.16
229.98 ± 5.05
Table 2: Algorithm performance (Mean Welfare ± Std. Dev.) on the Image Generation task across 20 independent trials. IAMFM-MFBO demonstrates a widening performance gap over baselines as the budget scales.
Appendix figures & tables9 assets
Supplementary material from the paper’s appendix.
Appendix
Strength
Label
Description for Prompt
0
Very Weak
minimal presence (indirect references only)
1
Weak
weak presence (subtle, background references)
2
Moderate
moderate presence (balanced, natural integration)
3
Strong
strong presence (prominent, featured examples)
4
Very Strong
very strong presence (dominant, detailed focus)
Appendix
Table 3: Mapping of numerical strength levels to prompt descriptions.
Regime
Comparison
Mean Diff.
p-value
95% CI 3 3 3 We report Welch 95% confidence intervals throughout. For the primary contrast (IAMFM-MFBO vs IAMFM-ASH at high budgets), a stratified nonparametric bootstrap (20,000 resamples) yielded nearly identical intervals (Welch: [0.21, 6.38]; bootstrap: [0.42, 6.33]), supporting the robustness of our conclusions.
Low-Budget ( ≤16k )
IAMFM-MFBO vs. UCB Bandit
+3.48
0.0003
[+1.63, +5.33]
IAMFM-MFBO vs. Uniform
+2.00
0.043
[+0.06, +3.93]
IAMFM-ASH vs. UCB Bandit
+4.47
<0.0001
[+2.40, +6.55]
IAMFM-ASH vs. Uniform
+2.99
0.0069
[+0.84, +5.14]
IAMFM-MFBO vs. IAMFM-ASH
+0.99
0.38 ns
[-3.22, +1.24]
High-Budget ( ≥32k )
IAMFM-MFBO vs. UCB Bandit
+3.69
0.0002
[+1.83, +5.54]
Appendix
Table 4: Statistical significance (Welch’s t-test) for key comparisons across budget regimes. We report p-values and 95% CIs for the mean difference. Bolded methods are our novel proposals.
Figure 3: Qualitative comparison. The naive greedy strategy (Config A) results in disjointed text where one advertiser overpowers the other, leading to hallucinations. IAMFM (Config B) identifies the optimal influence configuration, improving total welfare by +36% through enhanced semantic coherence.
User Weight ( wU )
Optimal s∗=(sA,sB)
E[VA]
E[VB]
E[Vuser]
wU=0.2
(4, 4)
52.41
73.56
60.02
wU=1
(2, 2)
51.59
72.46
63.77
wU=5.0
(2, 4)
44.18
77.17
65.62
Appendix
Table 5: Optimal configuration s∗ for different user utility weights ( wU ), calculated using F4 mean utilities aggregated across all 5 users. Restaurant A is “QuickBite” and B is “Thai Spice Garden”.
Scenario
Optimal s∗=(sA,sB)
E[VA]
E[VB]
A-Only ( argmaxE[VA] )
(3, 0)
52.44
57.07
B-Only ( argmaxE[VB] )
(0, 4)
45.18
77.72
Appendix
Table 6: Optimal configuration s∗ in advertiser-only extreme scenarios, using F4 aggregated means. The optimum is found by maximizing only E[VA] or E[VB] .
Figure 4: Absolute error (compared with the offline ground truth) in finding the best counterfactual welfare as a function of additional budget ( Bcf ). We compare our warm-start methods against their cold-start counterparts. The GP-based methods are shown in blue: ACO-MFBO (solid blue line) and Cold-Start MFBO (dashed blue line). The elimination-based methods are in green: ACO-ASH (solid green line) and Cold-Start ASH (dashed green line).
Figure 5: SAE Steering for promoting ice creams and lemons. Prompt: “Help me plan the perfect movie night tonight with 8 guests coming. What do I need to buy?” Columns steer for ice cream, and rows steer for lemon-related things.
Online advertising studies how digital ads are targeted, ranked, priced, measured, and delivered while balancing budgets, business goals, and user interests.
The commercialization of LLM applications is the next frontier in online advertising, with LLM-native advertising emerging as a promising paradigm by integrating ads into LLM-generated content. However, classic mechanisms are no longer applicable in this setting where the auction object is shifted from discrete ad slots to distributions over LLM outputs, and existing methods are impractical in industrial scenarios due to ignored externalities or high inference costs. To address these issues, we propose LLM-Auction, the first learning-based generative auction mechanism that integrates auction and generation. By formulating the allocation as preference alignment between LLM outputs and a mechanism objective that balances advertisers' value and user experience, we optimize the LLMs to inherently model allocation externalities without extra inference cost. Theoretically, we identify the allocation monotonicity and continuity of the optimal allocation rule of LLM-Auction, and prove that a simple first-price payment rule exhibits favorable incentive properties under this allocation rule. Furthermore, we build an LLM-as-a-judge simulation environment for quantitative evaluation, and experiments demonstrate that LLM-Auction achieves the state-of-the-art allocation efficiency while approximately satisfying key mechanism properties.
Generative AI is transforming how people access information, challenging traditional advertising mechanisms built around predefined slots. Towards generation-native advertising, we propose the Latent Advertiser Mixture Auction (LAMA), a token-level advertising mechanism that embeds advertiser influence directly into the generation process. Advertisers report local continuation values that induce advertiser-specific next-token policies, from which the platform decodes through a latent mixture while updating an allocation posterior. We show that LAMA satisfies Markov DSIC and IR, and achieves near-optimal KL-regularized welfare. We further develop a learning-based implementation that reconstructs the required reports online from learned local advantages and root values. Proof-of-concept experiments on real-world commercial-search query splits show that LAMA improves platform welfare and revenue while maintaining user-facing response quality, providing initial evidence for the feasibility of generation-native advertising.
Hanbing Liu, Bowei Zhang, Changyuan Yu +2
Renmin University of China Beijing, China · Beijing, China · Stanford University Stanford, CA, USA
Incentivized advertising allocates monetary or virtual rewards to drive user engagement, where a key challenge is optimizing continuous incentive magnitudes under strict global constraints. This problem is complicated by high-frequency interactions, delayed feedback, and non-Markovian user dynamics such as fatigue, which limit the effectiveness of existing uplift modeling and constrained reinforcement learning approaches. To address these challenges, we propose GOAL, a constraint-aware generative framework that formulates incentive allocation as a conditional sequence generation problem. GOAL directly generates incentive magnitudes conditioned on user histories and system-level global pressure, and integrates a hierarchical causal state encoder to capture both local behavioral dynamics and long-range dependencies. To enable flexible constraint control, we introduce Safe Constrained Policy Optimization (SCPO), which learns a single generative policy that generalizes across a spectrum of ROI constraints without retraining. Experiments on large-scale real-world data and a synthetic fatigue-aware environment show that GOAL improves long-term revenue and user retention while substantially reducing ROI violation rates compared to strong baselines.
Gege Chen, Ning Luo, Hao Jiang +7
University of Electronic Science and Technology of China · Kuaishou Technology