Bid optimization in online advertising relies on black-box machine-learning models that learn bidding decisions from historical data. However, these approaches fail to replicate human experts' adaptive, experience-driven, and globally coherent decisions. Specifically, they generalize poorly in data-sparse cases because of missing structured knowledge, make short-sighted sequential decisions that ignore long-term interdependencies, and struggle to adapt in out-of-distribution scenarios where human experts succeed. To address this, we propose KBD (Knowledge-informed Bidding with Dual-process control), a novel method for bid optimization. KBD embeds human expertise as inductive biases through the informed machine-learning paradigm, uses Decision Transformer (DT) to globally optimize multi-step bidding sequences, and implements dual-process control by combining a fast rule-based PID (System 1) with DT (System 2). Extensive experiments highlight KBD's advantage over existing methods and underscore the benefit of grounding bid optimization in human expertise and dual-process control.
Figures & tables
Figure 1: The architecture of the KBD method. Blue-shaded components denote black-box modules implemented via neural networks, yellow-shaded components indicate rule-based interpretable modules, and mixed-color regions represent their fusion.
Method
R/R∗↑
constraint satisfaction ↑
ARTEO ( Korkmaz et al., 2022 )
0.601
80.65%
BOCO ( Liang et al., 2023 )
0.618
74.10%
SPB ( Su et al., 2024b )
0.699
75.32%
PUROS ( Luo et al., 2024 )
0.723
81.73%
GCB-safe ( Castiglioni et al., 2025 )
0.606
80.77%
KBD w/o DT
0.706
81.43%
Table 1: Results of click maximization on iPinYou dataset.
Experimental Period
Group
Group Detail
cost-exhaust ratio
GMV
Campaign Duration
use PID
use IEFormer
use DT
2025/09/28-2025/10/18
Control Treatment
✓ ✓
✓
/ + 8.44%
/ + 6.14%
/ + 0.58%
2025/11/20-2025/12/10
Control Treatment
✓ ✓
✓
✓
/ +14.55%
/ +13.01%
/ +1.36%
2025/12/11-2025/12/31
Control Treatment
✓ ✓
✓ ✓
✓
/ +2.27%
/ +2.66%
/ +0.20%
Table 2: Online test results on ECA : relative lifts against control group; absolute metrics redacted for commercial confidentiality.
Figure 2: Case studies on the influence of Lmargin . As highlighted by the ellipsoidal regions, the price-volume curve is more prone to overfitting the noisy data without Lmargin .
Method
wmape ↓
mape ↓
perf10 ↑
w/o IE
0.2588
0.2348
0.2738
w/o GLA
0.2412
0.2270
0.2793
w/o Lmargin
0.2386
0.2268
0.2921
w/o tROI data
0.2226
0.2600
0.2976
KBD
0.2187
0.2151
0.3214
Table 3: Ablation Study of IML on ECA dataset.
Method
wmape ↓
mape ↓
IGCM ( Tang et al., 2025 )
0.9979
0.9949
GP ( Schulz et al., 2018 )
0.6414
1.8021
CMNN ( Li et al., 2024 )
0.6309
2.0599
DIPN ( Shen et al., 2021 )
0.6308
1.7647
SMNN ( Kim and Lee, 2024 )
0.6179
2.2503
SMM ( Igel, 2023 )
0.6023
1.6785
Table 4: Price-volume model performance on ECA dataset.
Figure 3: Robustness of IEFormer to segment number N.