Large vision-language models (VLMs) achieve strong performance on multimodal tasks but often suffer from hallucination and poor grounding in knowledge-intensive reasoning. We propose SmoGVLM, a small, graph-enhanced VLM that integrates structured knowledge with visual and textual modalities, using Graph Neural Networks. We investigate the effects of our method across a range of model sizes, from tiny (1.3B) to large (13B) models. Our results demonstrate that, when trained using our approach, a small model can achieve performance gains upto 16.24%, and surpass its larger counterparts, outperforming larger VLMs and strong fine-tuned baselines. These results highlight the potential of structured knowledge augmentation for efficient, smaller-scale multimodal reasoning systems.
Figures & tables
Figure 1: Overview of SmoGVLM. Language, image, and KG inputs are encoded, fused into a joint representation, and decoded into rationale and answer.
Sub-graph
Time
Similarity of top- 200
extraction method
Taken
triples with Answer
QA-GNN
7 hrs
0.232 ± 0.10
Proposed
40 min
0.312 ± 0.14
Table 1: Comparison of sub-graph extraction methods. Our strategy is much faster and yields higher answer similarity.
Model
Size
Method
Acc. (%)
LLaVA-Tiny
1.3 B
LoRA
53.22
LLaVA-Tiny
1.3 B
FFT
62.72
SmoGVLM-Tiny
1.3 B
LoRA
69.46
SmoGVLM-Tiny
1.3 B
FFT
75.27
LLaVA
7 B
LoRA
69.41
LLaVA
7 B
FFT
69.42
Table 2: Performance on ScienceQA test split.
Model
Size
Method
Acc. (%)
LLaVA-Tiny
1.3 B
FFT
70.4
SmoGVLM-Tiny
1.3 B
FFT
70.7
LLaVA
7 B
FFT
79.3
SmoGVLM
7 B
FFT
79.5
Table 3: Performance on A-OKVQA validation split.
Figure 2: Similarity of top- k triples to the correct answer.
Model
Size
Method
# Nodes
Acc. (%)
LLaVA
7 B
FFT
-
69.42
50
83.94
SmoGVLM
100
86.65
200
86.87
Table 4: Impact of sub-graph size on accuracy. Small graphs are sufficient, with performance saturating beyond 200 nodes.
Figure 3: A few qualitative samples showing the strengths and limits of structured knowledge with VLMs.