Cross-Relational Preference Learning for Better LLM Instruction Following
Authors: Runsheng Li, Kai Sun, Bin Shi, Bo Dong
Organizations: School of Computer Science and Technology, Xi’an Jiaotong University, Xi’an, Shaanxi 710049, China · Shaanxi Provincial Key Laboratory of Big Data Knowledge Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi 710049, China · School of Distance Education, Xi’an Jiaotong University, Xi’an, Shaanxi 710049, China
Large Language Models (LLMs) still exhibit limited capability in following complex instructions. While existing approaches often rely on preference learning to enhance this ability, they typically overlook the relationships between the permissible response spaces of different instructions, which restricts a model to align with subtle and diverse constraint variations. To address this, we propose Cross-Relational Preference Learning (CRPL), a novel framework for constructing preference data that explicitly models inter-instruction relationships through two key techniques: Cross-Relationship Perturbation and Cross-Region Pair Sampling. This enables the generation of more diverse preference data that captures a wide spectrum of constraint variations. Additionally, we introduce an atomic constraint-based verification mechanism to rigorously assess response satisfaction, ensuring high-quality preference pair construction. Extensive experiments across multiple preference learning methods (e.g., DPO, KTO), LLM backbones and four instruction-following benchmarks demonstrate that our approach achieves substantial improvements over prior baselines and exhibits strong generalization.
Figures & tables
Figure 1: Relationships between the permissible response spaces of an original instruction and its perturbed variant. Colors denote: red — original instruction’s response space; green — perturbed instruction’s response space; blue — intersection of the two spaces.
Figure 2: An overview of our Cross-Relational Preference Learning (CRPL) framework. (1) Cross-Relationship Perturbation: We decompose the original instruction into atomic constraints and generate perturbed instructions that exhibit specific response-space relationships (containment, partial overlap, or disjoint) with the original one. (2) Cross-Region Pair Sampling: Guarded by an atomic constraint-based verification mechanism, we sample positive and negative responses from distinct sub-regions of the combined response space to construct diverse, high-quality preference pairs.
Method
Training size
IFEval
IFBench
Perturbed-IF
FollowBench
Avg.
Accins
Acccon
Accins
Acccon
Accins
Acccon
Accins
Acccon
Backbone: Qwen2.5-7B-Instruct
Qwen2.5-7B-Instruct
-
71.2
78.7
26.5
29.0
42.5
65.0
50.9
58.2
52.8
Training strategy: DPO
Rejection Sampling
12k
75.7
81.0
24.8
26.3
51.0
66.6
46.2
55.6
53.4
From Complex to Simple
12k
74.1
81.6
27.6
29.9
45.5
64.8
51.6
58.5
54.2
Table 1: Performance comparison of our method against prior baselines across the four test sets. For each backbone and training strategy, the best and second-best accuracy scores are highlighted in bold and underlined , respectively. OursIFEval and OursIFBench indicate models trained on the IFEval and IFBench training sets, respectively.
Model
Original
Containment-1
Containment-2
Partial Overlap
Disjoint
Accins
Acccon
Accins
Acccon
Accins
Acccon
Accins
Acccon
Accins
Acccon
Qwen2.5-7B-Instruct
71.2
78.7
53.7
71.0
58.8
73.2
50.0
67.9
51.2
70.1
Rejection Sampling
75.7
81.0
57.5
75.0
60.0
75.6
55.0
72.8
62.5
73.7
From Complex to Simple
84.1
81.6
62.5
76.7
60.0
72.6
50.0
69.1
53.7
70.1
AutoIF
84.1
81.0
51.2
72.7
57.5
73.2
50.0
70.4
51.2
71.9
Ours
90.7
94.3
68.8
80.7
67.5
80.4
62.5
79.6
68.8
80.2
Table 2: Performance on original instructions and four types of perturbed instructions. Containment-1 and Containment-2 represent two subtypes of containment relationships, namely containing and contained.
Figure 3: Performance scaling with training data size for DPO (left) and KTO (right) across different methods.
Method
Accins
Acccon
Ours
90.7
94.3
w/o Containment-1
85.9
90.7
w/o Containment-2
84.7
88.8
w/o Partial Overlap
84.3
88.8
w/o Disjoint
82.9
87.2
Table 3: Ablated results on different relationship types.
Method
Accins
Acccon
Ours
81.3
85.6
w/o Pair1
77.1
82.5
w/o Pair2
77.3
83.1
w/o Pair3
78.5
83.5
w/o Pair4
79.2
84.2
Table 4: Ablated results on cross-region pair sampling.
Method
TP
FP
TF
NF
Accins
Acccon
ACV (ours)
66
0
27
15
85.4
89.2
ILV
47
0
27
34
84.0
88.7
LAJ
52
4
23
29
80.8
85.8
Table 5: Performance comparison for different verification methods.
Appendix figures & tables8 assets
Supplementary material from the paper’s appendix.
Appendix
Parameter
DPO
KTO
Learning Rate
1e-5
1e-5
Train Batch Size
32
32
Micro Train Batch Size
8
8
Max Sequence Length
5102
5102
Beta
0.1
0.1
Max Epochs
2
3
Appendix
Table 6: Ablated results on different relationship types.
Model
Data
IFEval
IFBench
Accins
Acccon
Accins
Acccon
Qwen2.5-14B-Instruct
-
85.0
89.1
33.2
35.4
OursIFEval
88.2
91.5
36.1
38.1
OursIFBench
88.2
92.1
41.6
44.3
Qwen3-8B
-
89.4
93.4
25.6
28.0
OursIFEval
89.1
93.1
29.6
31.3
Appendix
Table 7: Performance of Our Method across Different Backbone Models.
Figure 4: Prompt for instruction decomposition
Figure 5: Prompt for generating evaluation functions for atomic constraints.
Figure 6: Prompt for the first type of containment relationship perturbation. The valid response space of the original instruction contains that of the perturbed instruction.
Figure 7: Prompt for the second type of containment relationship perturbation. The valid response space of the perturbed instruction contains that of the original instruction.
Figure 8: Prompt for the partial overlap relationship perturbation.
Figure 9: Prompt for the disjoint relationship perturbation.