Findings of EMNLP 2026

Do Vision-Language Models
Understand Visual Persuasiveness?
A Diagnosis via Visual Persuasive Factors

Gyuwon Park1Hyounghun Kim1,2

1Graduate School of Artificial Intelligence, POSTECH

2Department of Computer Science and Engineering, POSTECH

POSTECHLIL
Paper Code BibTeX

PROJECT SUMMARY

Seeing the cue is only the beginning.

Can a vision-language model tell whether an image persuasively supports a message? We study 562 image–message pairs with high human agreement and find that VLMs frequently mistake persuasion-relevant visual cues for sufficient evidence of persuasiveness.

We introduce Visual Persuasive Factors (VPFs) to diagnose this gap across three levels: perceptual, compositional, and semantic. Contextual framing of these cues can improve judgments, but connecting visual evidence to communicative intent remains a central bottleneck.

Understanding visual persuasiveness

An image can contain relevant objects, people, and text without effectively supporting its intended message. Our framework compares human and model judgments, then examines the visual factors behind their differences.

Overview of the human–VLM persuasion evaluation and perceptual, compositional, and semantic visual persuasive factors.
VLMs over-predict high persuasiveness even when all four human annotators agree on a low judgment. VPFs organize the visual cues behind these judgments into three diagnostic levels.

THE DIAGNOSTIC FRAMEWORK

Three levels of visual persuasive factors

01 / PERCEPTUAL

How it looks

Immediate visual impressions and their alignment with the persuasion strategy.

  • Colorfulness & color entropy
  • Representative color congruence
  • Brightness & strategy alignment
02 / COMPOSITIONAL

Where cues appear

The placement of visual attention and message-relevant regions.

  • Center bias
  • Rule-of-thirds coverage
  • Saliency & message-relevant regions
03 / SEMANTIC

What is present

Content cues that may contribute to the intended persuasive appeal.

  • Key object presence
  • Human presence
  • Text presence

Validated with independent human judgments

A separate survey with 141 annotators finds higher perceived factor importance for high-persuasiveness items across all nine factors. VPFs provide an interpretable diagnostic lens; they are not an exhaustive model of visual persuasion.

Human survey comparing the perceived influence of nine visual persuasive factors for high and low persuasiveness items.
Independent annotators rate the influence of each VPF on a five-point scale. High items receive significantly higher factor-importance ratings across all nine factors.

FINDING 01

High recall, limited persuasive understanding

Across model families, VLMs tend to label too many images as persuasive. High recall comes with low precision, exposing a recall-oriented bias.

Baseline persuasive judgment performance (%) — excerpt from the full intervention table below
ModelAccuracyPrecisionRecallF1
GPT-569.5751.0198.8867.30
GPT-5-mini60.1444.1397.1960.70
Gemma363.8846.3388.7660.89
Qwen2.5-VL54.9840.5189.8955.85

Relevant cues can also drive false positives

VPFs distinguish human high and low judgments, but models reproduce these patterns only partially. Among human-labeled low items, key objects, people, and text can become generic positive signals, causing models to overgeneralize from cue presence to persuasiveness.

A relevant object is a candidate piece of evidence. Whether it supports the message still needs to be evaluated.

Human–VLM comparison across VPFs

Effect size: s · smallm · mediuml · largen · negligible (no shading)
GroupRowPerceptual (%)Compositional (%)Semantic (OR)
ColorBrightnessCBIT3KeyObjHumanText
ColorfulnessEntropyRep.
Congruence
RawPosNegSaliencyMRRSaliencyMRR
Panel A: Ground Truth
HumanΔ_f(Y)-3.94**s4.57***s15.09***s-0.34n-5.11s5.91**s2.65**s-2.83n3.19***s3.31**s3.36***m1.25n0.60*s
Panel B: VLM Predictions
GPT-5Δ_f(Y)-1.66n4.82***s12.34***s-1.69n-5.74*s4.19*s3.27***s2.45n2.58***s1.23n2.87***m1.56*s0.94n
GPT-5-miniΔ_f(Y)-3.51*s-3.68**s16.19***s-1.84n-6.92*s6.67**s2.90***s1.46n2.65***s0.67n2.68***m1.58*s1.35n
Gemma3Δ_f(Y)-2.87n3.08**s15.04***s-0.67n-6.30*s7.99***m7.01***m4.73*s4.97***m2.78*s2.03***s1.88**s1.37n
Qwen2.5-VLΔ_f(Y)-2.51n4.99***s14.41**s0.86n-5.35s8.78***m6.15***m1.60n5.49***l4.73***s2.73***m2.48***m1.47s
Panel C: VLM False Positives among Ground-Truth Low Items
GPT-5Δ_f(FP-TN)0.31n3.28*s4.60n-2.83n-6.10s0.51n0.42n0.26n1.31n-0.66n2.18***s1.72*s1.19n
GPT-5-miniΔ_f(FP-TN)-2.05n2.29n7.80n-2.53n-5.99s3.81s1.06n-0.90n1.78*s1.28n2.02**s1.53s1.79*s
Gemma3Δ_f(FP-TN)-0.93n2.90s6.00n-1.90n-6.69*s5.99*s2.23*s1.64n2.47**s0.85n1.41n1.96**s1.63*s
Qwen2.5-VLΔ_f(FP-TN)-1.73n4.20**s14.60**s0.31n-5.35s8.08**s3.60**s0.49n3.42***m-0.21n1.99**s2.17***s1.56n

Human–VLM comparison summary across VPFs. Panel A shows that VPFs separate human-labeled High and Low items, while Panel B shows that VLM predictions partially reproduce this human-aligned pattern. Panel C further analyzes VLM false positives among ground-truth Low items, revealing that models often associate persuasion-relevant cues with erroneous High predictions. Overall, VLMs appear sensitive to several persuasive cues, but their false positives suggest an overgeneralization from persuasive cues to High persuasiveness.

VPFs provide complementary predictive signals

VLM SourceInput FeaturesAcc. (%)AUC (%)ΔAUC (pp)
–VPFs69.571.8–
GPT-5VLM pred.72.078.8–
GPT-5VLM pred. + VPFs75.985.1+6.3
GPT-5-miniVLM pred.66.770.5–
GPT-5-miniVLM pred. + VPFs71.379.6+9.1
Gemma3VLM pred.66.471.0–
Gemma3VLM pred. + VPFs73.179.9+8.9
Qwen2.5-VLVLM pred.66.764.5–
Qwen2.5-VLVLM pred. + VPFs70.275.4+10.9

VPF-aware prediction of human ground-truth labels. VPFs carry predictive signal and provide additive gains beyond VLM predictions in logistic regression.

FINDING 02

How visual knowledge is framed matters

Factor-aware Cognitive Injection frames VPFs as context-dependent auxiliary cues and generally reduces false positives while improving F1. Simply supplying aligned key objects, however, lowers F1 across the evaluated models. General chain-of-thought and structured reasoning scaffolds show mixed effects.

F1 changes under factor-aware cognitive injection for each visual persuasive factor across four models.
Factor-aware Cognitive Injection: F1 changes relative to each model’s baseline when VPF knowledge is introduced as context-dependent supporting information. See the paper for full intervention comparisons.

Semantic grounding and reasoning scaffolds

Non-Aware Key Object
ModelBaselineChain-of-ThoughtsKnowledge-Conditioned Chain
Acc.Prec.Rec.F1Acc.Prec. (Δ)Rec. (Δ)F1 (Δ)Acc.Prec. (Δ)Rec. (Δ)F1 (Δ)
GPT-569.5751.0198.8867.3070.1151.52 ↑0.5194.94 ↓3.9466.80 ↓0.5065.4847.81 ↓3.2098.31 ↓0.5764.34 ↓2.96
GPT-5-mini60.1444.1397.1960.7063.8846.63 ↑2.5097.19 (0.00)63.02 ↑2.3263.3546.30 ↑2.1798.31 ↑1.1262.95 ↑2.25
Gemma363.8846.3388.7660.8951.2538.84 ↓7.4993.82 ↑5.0654.93 ↓5.9639.1533.98 ↓12.3597.75 ↑8.9950.43 ↓10.46
Qwen2.5-VL54.9840.5189.8955.8568.0949.82 ↑9.3176.40 ↓13.4960.31 ↑4.4657.6542.46 ↑1.9594.94 ↑5.0558.68 ↑2.83
Aware Key Object
ModelAligned Key Object ContextKey Object-Aware CoTRationale Injection
Acc.Prec. (Δ)Rec. (Δ)F1 (Δ)Acc.Prec. (Δ)Rec. (Δ)F1 (Δ)Acc.Prec. (Δ)Rec. (Δ)F1 (Δ)
GPT-569.9351.44 ↑0.4390.45 ↓8.4365.58 ↓1.7263.7046.41 ↓4.6094.38 ↓4.5062.22 ↓5.0869.4050.89 ↓0.1296.07 ↓2.8166.54 ↓0.86
GPT-5-mini58.7243.11 ↓1.0294.94 ↓2.2559.30 ↓1.4054.9841.18 ↓2.9598.31 ↑1.1258.04 ↓2.6664.0646.79 ↑2.6698.31 ↑1.1263.41 ↑2.71
Gemma362.2845.06 ↓1.2787.08 ↓1.6859.39 ↓1.5046.4436.89 ↓9.4497.19 ↑8.4353.48 ↓7.4159.7943.65 ↓2.6892.70 ↑3.9459.35 ↓1.54
Qwen2.5-VL53.0239.56 ↓0.9591.57 ↑1.6855.25 ↓0.6062.4645.22 ↑4.7187.64 ↓2.2559.66 ↑3.8153.9139.37 ↓1.1484.27 ↓5.6253.67 ↓2.18

Results of semantic grounding and reasoning scaffolds on VLM performance. Δ next to Precision, Recall, and F1 shows the absolute percentage-point change relative to the model's own baseline scores (↑/↓ for direction).

Cognitive injection: average effects across models

Injection TypeΔFP RateΔPrec.ΔRec.ΔF1No. of Models
with F1 Gain
Panel A. Factor-wise Cognitive Injection
Color↓5.60↑1.98↓2.81↑1.063/4
Brightness↓5.01↑2.15↓0.70↑1.763/4
Saliency-Center↓5.66↑2.10↓2.39↑1.303/4
MRR-Center↓5.34↑2.12↓1.54↑1.533/4
Saliency-RoT↓7.68↑3.25↓2.25↑2.324/4
MRR-RoT↓5.08↑1.94↓1.54↑1.383/4
KeyObj↓3.91↑1.46↓1.69↑0.884/4
Human↓9.38↑3.61↓4.35↑1.954/4
Text↓5.27↑2.13↓1.40↑1.523/4
Panel B. All-factor Cognitive Injection
All↓1.03↑0.42↓0.28↑0.312/4

Average false-positive mitigation and performance effects of cognitive injection across four VLMs relative to each model's baseline in Tab. [paper]. All Δ values are computed as injection - baseline.

FINDING 03

Where does persuasive integration break down?

We decompose model-generated rationales into three functional steps and selectively remove them to examine how each part affects the final prediction.

S1

Object identification

Identify the relevant visual object.

S2

Message alignment

Explain how it supports or undermines the message.

S3

Judgment connection

Connect the evidence to the persuasive judgment.

Step ablation results showing item impact rates and changes in accuracy after removing individual or paired rationale steps.
All three rationale steps affect model behavior. Removing S1 + S2 improves accuracy across models, while removing S3 alone tends to hurt performance more directly.

The diagnosis points to a weakness in connecting object identification and semantic message alignment to the final persuasive claim. Identifying visual evidence and describing its relevance do not guarantee that the model integrates it appropriately.

Key takeaways

  1. Visual factors offer an interpretable diagnostic lens. Perceptual, compositional, and semantic cues distinguish human persuasive judgments.
  2. VLMs often overgeneralize from cue presence. Models partially capture human patterns but over-predict persuasiveness.
  3. Persuasive integration remains the bottleneck. Contextual cue framing helps; reliable judgment requires connecting visual evidence to communicative intent.

Citation

@misc{park2025visionlanguagemodelsunderstandvisual,
  title={Do Vision-Language Models Understand Visual
         Persuasiveness? A Diagnosis via Visual Persuasive Factors},
  author={Gyuwon Park and Hyounghun Kim},
  year={2025},
  eprint={2511.17036},
  archivePrefix={arXiv},
  primaryClass={cs.CL},
  url={https://arxiv.org/abs/2511.17036}
}