다중모드 언어모델에서 나타나는 프롬프트 매개 지각적 동조는 사회적 영향 이론을 따른다

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접수: 6월 29, 2026. 승인: 10월 29, 2026. 게재: 11월 3, 2026. https://doi.org/10.56296/aip00072 · © 2026 저자

저자 정보

: Centro Ricerche Enrico Fermi, Rome, Italy; Sony Computer Science Laboratories – Rome, Joint Initiative CREF–SONY, Rome, Italy; Physics Department, Sapienza University of Rome, Rome, Italy; University of Konstanz, Konstanz, Germany

: Centro Ricerche Enrico Fermi, Rome, Italy; University of Konstanz, Konstanz, Germany; Complexity Science Hub, Vienna, Austria

: University of Konstanz, Konstanz, Germany; Complexity Science Hub, Vienna, Austria; Barcelona Supercomputing Center, Barcelona, Spain

*연락처: Alessandro Bellina, [email protected], Museo Storico della Fisica e Centro Ricerche Enrico Fermi, Via Panisperna 89 A – 00184 Roma (Italy)

투명한 동료 심사

본 연구 논문은 이 출판 형식에 대한 저널 정책에 따라 편집상의 검토만을 거쳤습니다.

인용 정보

Bellina, A., Marzo, G.D., & Garcia, D. (2026). Prompt-mediated perceptual conformity in multimodal language models follows Social Impact Theory. advances.in/psychology, 1, e680902. https://doi.org/10.56296/aip00072

Bellina, Alessandro, et al. "Prompt-mediated perceptual conformity in multimodal language models follows Social Impact Theory." advances.in/psychology, vol. 1, no. 1, 2026, e680902. https://doi.org/10.56296/aip00072.

Bellina, Alessandro, Giordano De Marzo, and David Garcia. 2026. "Prompt-mediated perceptual conformity in multimodal language models follows Social Impact Theory." advances.in/psychology 1 (1): e680902. https://doi.org/10.56296/aip00072.

Bellina A, Marzo GD, Garcia D. Prompt-mediated perceptual conformity in multimodal language models follows Social Impact Theory. advances.in/psychology. 2026;1(1):e680902. doi:10.56296/aip00072.

Bellina, A. et al. (2026) 'Prompt-mediated perceptual conformity in multimodal language models follows Social Impact Theory', advances.in/psychology, 1(1), e680902. Available at: https://doi.org/10.56296/aip00072.

본 번역은 제목, 초록 및 핵심 요점에 대한 AI 생성 번역이며, 논문 본문은 영어로 유지됩니다.

초록

AI 에이전트가 다른 모델 및 인간과 함께 다중 에이전트 환경에서 점점 더 많이 작동함에 따라, 이들이 프롬프트에서 접하는 의견에 어떻게 반응하는지를 이해하는 것은 이러한 상호작용의 결과를 예측하는 데 매우 중요해지고 있다. 본 연구는 AI 에이전트로 기능하는 대규모 다중모드 언어모델에서 집단 의견에 동조하려는 경향, 즉 동조와 유사한 행동을 검토한다. 사회심리학의 고전적 시각 실험을 변용하여, 우리는 이러한 에이전트가 프롬프트에 포함된 사회적 신호에 어떻게 반응하는지를 조사하였다. 실험 결과 AI 에이전트는 사회적 영향 이론(Social Impact Theory)과 일치하는 체계적인 동조 편향을 보였다. 이들의 반응은 다수의 규모, 집단의 만장일치 여부, 과제 난이도, 그리고 지각된 권위와 집단 소속 공유를 포함한 출처 특성에 따라 달라졌다. 결정적으로, 단독으로는 거의 완벽에 가까운 수행을 보이는 AI 에이전트가 사회적 영향을 통한 조작에 매우 취약해졌다. 이러한 취약성은 모델 규모 전반에 걸쳐 지속되었다. 즉, 더 큰 모델은 단순한 과제에서는 동조 편향이 감소하였으나, 과제가 어려울 때에는 여전히 취약하였다. 이러한 결과는 AI 에이전트의 의사결정에 존재하는 보안 취약성을 드러내며, 이는 악의적 조작, 허위정보 캠페인, 그리고 다른 모델 및 인간과의 상호작용에서의 편향 전파를 가능하게 할 수 있어, AI 배치에 있어 안전장치의 시급한 필요성을 부각한다.
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핵심 요점

  • 단독으로는 단순한 시각적 질문에 거의 완벽하게 답하는 AI 시각-언어 모델도, 프롬프트에서 다른 '참가자들'이 오답을 제시하는 것을 보면 오답으로 이끌릴 수 있다. 12개의 오픈소스 다중모드 모델 전반에서 오류 확률은 처음 몇 명의 협조자(confederate)에 걸쳐 가파르게 상승한 뒤 중앙값 66%에서 평탄해졌다. 이 수준은 Asch 식 실험에서 인간에게서 통상적으로 관찰되는 30~40%의 오류율을 크게 상회한다.
  • 집단의 크기보다 집단을 구성하는 사람이 누구인지가 더 중요했다. 만장일치로 오답을 제시한 두 명의 협조자는 절반이 정답을 제시한 열 명의 협조자보다 오류 확률을 더 크게 높였다(0.31 대 0.20). 모델은 더 확신하는 자극에서 덜 동조하였다(Spearman ρ 중앙값 = −0.91, 32개 모델–과제 조합 중 30개에서 음수). 모델이 가장 확신한 자극에서조차 동조 편향은 모든 모델과 과제에서 0보다 크게 유지되었다.
  • 모델의 행동은 사회적 영향 이론의 예측과 일치하였다. 협조자를 전문가로 명명하면 동조 편향이 최대 0.13까지 증가한 반면, 아동이나 챗봇으로 명명하면 최대 0.06까지 감소하였다. '경찰관'이나 '군 장교'와 같은 순수한 권위 명칭은 일관된 효과를 보이지 않았으며, 모델–과제 조합의 약 절반에서만 동조를 증가시켰다. 국적을 공유하거나 심지어 임의의 집단 명칭을 공유하는 것만으로도 32개 조합 전부에서 동조가 증가하였다. 모델에게 그 답변이 공개될 것이라고 알리면 32개 조합 중 27개에서 동조가 증가하였으며, 그중 21개에서는 신뢰구간이 0을 포함하지 않았다.
전문은 영어로 이어집니다

Introduction

The rapid advancement of large language models (LLMs) (OpenAI et al., 2023) has catalyzed the emergence of sophisticated AI agents capable of autonomous decision-making (Park et al., 2023). These agents demonstrate remarkable individual capabilities spanning code generation (Jimenez et al., 2023; Yang et al., 2024), medical diagnosis (Singhal et al., 2023), mathematical reasoning (DeepMind, 2025; Romera-Paredes et al., 2024), and scientific research (Boiko et al., 2023; Novikov et al., 2025), often achieving human or super-human performance on specific tasks (OpenAI et al., 2023). However, the next frontier lies not in creating ever-more-capable individual models, but in developing systems where multiple AI agents coordinate effectively at scale. This paradigm shift is already emerging through frameworks such as AutoGPT, Concordia (Vezhnevets et al., 2023), Microsoft’s AutoGen (Wu et al., 2024), and OpenAI’s SWARM, which enable meaningful interaction between agents rather than simple ensembling of models. As these agents increasingly operate alongside one another, from automated trading systems that can trigger flash crashes (Johnson et al., 2013) to collaborative platforms that coordinate complex workflows (Shen et al., 2023), understanding how the context they receive shapes their answers becomes crucial for anticipating the dynamics of AI-driven systems.

A key determinant of group dynamics in any social system is conformity, the tendency of individuals to adjust their judgments, attitudes, or behaviors to align with those of a group, particularly when under perceived social pressure (Asch, 1955; Sherif, 1935, 1936). This phenomenon has been the subject of extensive research over the past decades (Bond & Smith, 1996; Cialdini & Goldstein, 2004; Deutsch & Gerard, 1955). In human societies, conformity serves dual functions: it promotes group cohesion, facilitates social learning, and enables the transmission of social norms (Kelman, 1958; Turner, 1991), yet it can also lead to the suppression of dissent, systematic misjudgment, and the propagation of errors (Janis, 1972; Sunstein, 2006). As we deploy increasing numbers of AI agents in collaborative settings, understanding whether and how they exhibit conformity-like behaviors becomes essential for predicting the stability, efficiency, and potential vulnerabilities of these systems.

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Decades of research in social psychology have identified the key mechanisms underlying human conformity. The classic experiments by Solomon Asch (1956, 2016) demonstrated that individuals conform to group judgments even when the objective reality is unambiguous, with conformity influenced by factors such as the size of the majority (Asch, 1956; Bond, 2005; Gerard et al., 1968; Rosenberg, 1961), the unanimity (Allen, 1965; Asch, 1955; Moscovici et al., 1969; Nemeth, 1986), the ambiguity of tasks (Crutchfield, 1955; Gergen & Bauer, 1967; Hertz & Wiese, 2016; Klein, 1972; Nordholm, 1975), and the characteristics of the source, including perceived authority and group membership (Abrams et al., 1990; Bickman, 1974; Blass, 1991; Brewer, 1993; Crandall et al., 2002; Hofling et al., 1966; Hogg & Abrams, 1999; Hogg & Turner, 1987; Latané, 1981; Latané & Nida, 1981; Latané & Wolf, 1981; Mackie, 1986; McPherson et al., 2001; Milgram, 1963; Tajfel et al., 1971). Cultural background and demographic traits have also been shown to affect susceptibility to social pressure (Bond & Smith, 1996). These results lead to the Social Impact Theory (Latané, 1981; Latané & Nida, 1981; Latané & Wolf, 1981), which formalizes conformity as a function of three core variables: the number (N) of influencing agents, their strength (S) (e.g., perceived authority or expertise) and their immediacy (I), defined as social, spatial, or temporal proximity.

Recent evidence suggests that AI agents exhibit individual and collective behaviors that resemble human behavior across various social and cognitive tasks (Argyle et al., 2023; Ashery et al., 2025; Binz & Schulz, 2023; De Marzo et al., 2023, 2024; Ganguli et al., 2023; Schramowski et al., 2022), and reflect the opinions and values of particular human groups (Buyl et al., 2026; He et al., 2024; Santurkar et al., 2023). Recent work has also documented conformity-like responses to majority answers in text-based question-answering and multi-agent reasoning settings (Weng et al., 2025; Zhu et al., 2025). These studies measure how often a model adopts the majority answer, and relate it to the model’s own uncertainty and instruction tuning, to the tone and size of the majority, and to the duration of the interaction. A concurrent benchmark poses the question for multimodal models on existing datasets (Luo et al., 2026), and related work asks what the composition of a majority contributes beyond its size (Denton et al., 2026), whether the effect reflects informational or normative influence (Zhong et al., 2025), and how much of the shift survives once the social frame is removed from the prompt (Hu & Qu, 2026). Although the underlying mechanisms driving these similarities, whether emergent social cognition, learned patterns from training data, in-context learning, or artifacts of reinforcement learning from human feedback, remain an open question (Barrie & Törnberg, 2025), our focus is pragmatic: understanding how conformity-like patterns manifest in multimodal AI agents and identifying the factors that modulate their strength. This behavioral characterization is essential for predicting and managing the dynamics of deployed AI systems (Rahwan et al., 2019), regardless of the specific mechanisms that give rise to these patterns.

Figure 1
Summary of the experimental setup. Illustration of the general experimental setting for the three visual tasks: line judgment, color recognition, and dots estimation. Each prompt consists of four main components: the image, the question, the \(N\) prior responses sampled from a pool of naturalistic answers, and a closing instruction to answer with a single label. In the baseline condition (\(N=0\)) the third component is omitted. Variants of this setup, used across the different experimental conditions, are described in Section 2. Full prompt examples are provided in Section S1.

Summary of the experimental setup. Illustration of the general experimental setting for the three visual tasks: line judgment, color recognition, and dots estimation. Each prompt consists of four main components: the image, the question, the N prior responses sampled from a pool of naturalistic answers, and a closing instruction to answer with a single label. In the baseline condition (N=0) the third component is omitted. Variants of this setup, used across the different experimental conditions, are described in Section 2. Full prompt examples are provided in Section S1.

The implications of conformity in AI agent deployments are profound and bidirectional. Positive conformity effects could enhance coordination, stabilize group decision-making, and facilitate the emergence of beneficial social norms, critical capabilities as AI agents increasingly collaborate on complex tasks (Ashery et al., 2025; De Marzo et al., 2026). Conversely, excessive conformity poses significant risks: it could amplify misinformation, suppress innovative solutions, create systemic vulnerabilities to manipulation, and lead to cascade failures when groups of agents converge on incorrect decisions. Understanding these dynamics is essential as AI agents transition from isolated tools to interconnected systems operating at unprecedented scales.

In this study, we systematically examine conformity-like behavior in large multimodal language models by adapting classic visual experiments from human social psychology to AI agent contexts. We use twelve open-source models, from 3 to 34 billion parameters, whose output logits give a continuous measure of each answer. The experiments are conducted in a single-agent prompt setting: the model observes prior responses attributed to other participants, without explicitly interacting with other agents. Rather than attempting to simulate human cognition, we investigate how AI agents shift their answers when exposed to group pressure in the prompt. By manipulating factors known to influence human conformity, including group size, unanimity, and source characteristics, we evaluate whether analogous contextual variables modulate AI agent susceptibility to social influence. Our contribution is a systematic test of conformity-like behavior through the lens of Social Impact Theory, quantifying the role of the number, strength and social composition of the sources together with that of task difficulty and model performance.

Methods

Experimental Settings

General Task Preparation

All experiments share a common core setup, upon which targeted variations are introduced to isolate specific factors influencing conformity. In each trial, the model is presented with a visual discrimination task based on a synthetic image. We consider three types of tasks:


  • line judgment: the image displays three vertical lines labeled “A,” “REFERENCE LINE,” and “B.” The model must identify whether line A or B matches the length of the reference.



  • color recognition: the image shows three colored squares labeled “A,” “REFERENCE COLOR,” and “B.” The model must choose the square that matches the reference color.



  • dots estimation: the image includes three boxes containing a number of dots, labeled “A,” “REFERENCE BOX,” and “B.” The model is asked to identify which box has the same number of dots as the reference.


Examples of the stimuli used for each task are shown in Figure 1. For each trial, we randomly generate new images by varying relevant visual properties (e.g., line lengths, colors and dot counts) as well as the position of the correct option (A or B), to minimize biases related to spatial layout or label preference. We also report, in the Supplementary Materials (Section S5), the results of the experiments on a fourth task, the recognition of handwritten digits (MNIST; LeCun et al., 1998). This task lies outside the classical paradigms of the conformity literature and serves to rule out that the models reproduce results memorized from it.

To control for baseline model accuracy, we first evaluate the probability of a correct response in the absence of prior-response context, denoted as \(p_{\text{correct}}(0)\). All experiments are conducted using only images that the model, with no prior-response context, answers correctly with probability at least \(0.85\) (median \(p_{\text{correct}}(0)\) above \(0.99\) across models and tasks; Section S3), ensuring that the model reliably understands the task under neutral conditions. This guarantees that conformity effects are not confounded by baseline performance or perceptual misinterpretations. This filtering was possible for all models in the color recognition task, which only requires reading and comparing pixel-level RGB values. For the line judgment and dots estimation tasks, we excluded the Qwen2 7B and Qwen2.5 3B models, as even under the easiest configurations they could not reach the required baseline accuracy. The analyses therefore cover 32 combinations of model and task: twelve models on color recognition and ten on each of the other two tasks.

In each test, the model is instructed to respond with a single letter corresponding to one of the options (\(A\) or \(B\)). From the logits of the two tokens we obtain the probability of the correct and of the incorrect answer, \(p_{\text{correct}}\) and \(p_{\text{wrong}}\), respectively; we refer to the latter as the error probability. We vary the number of confederates \(N\) and quantify the tendency to follow the incorrect majority through \(p_{\text{wrong}}(N)\). We define the conformity bias as the area under the error probability curve \(p_{\text{wrong}}(N)\) across group sizes, net of the baseline error probability.

Group Size and Unanimity

For each model and task, we use a pool of 61 to 64 images that satisfy this criterion. The baseline prompt, corresponding to the no-pressure condition (\(N = 0\)), is illustrated in Figure 1.

To create the prior-response condition, we augment the prompt by stating that other participants, hereafter confederates, have provided answers (always incorrect for Figure 2a). These responses are randomly sampled from a neutral-sounding pool of statements, detailed in the Supplementary Materials (SM). We vary the number of confederates \(N\), and for each value, we measure the error probability \(p_{\text{wrong}}(N)\) (probability of producing the incorrect answer). Natural language is the closest analogue of the human paradigm and the form we report throughout; the effect is unchanged when only the bare answers are shown (Section S4). This process is repeated for 61 to 64 random trials per value of \(N\).

In the unanimity condition (Figure 2c), we vary not only the number of confederates but also the proportion of them giving correct answers. This allows us to test the effect of broken unanimity. The exact prompts used for each condition are reported in the SM.

Task Difficulty

In all tasks, the level of difficulty is determined directly from the parameters used to generate the synthetic images. This allows for an objective and model-independent measure of task complexity, based purely on visual differences between the correct and incorrect options.

For the color recognition task, images are generated from two RGB vectors: one for the reference color, and one for the distractor color. The larger the difference between them, the easier the task. We define a simplicity index for each image as \(\text{simplicity(image)} = \Delta \text{RGB}\), where \(\Delta \text{RGB}\) is the Euclidean distance between the two color vectors. The task difficulty used in Figure 3b is then defined as the maximum simplicity value minus the simplicity of the given image, so that higher values correspond to higher difficulty.

For the line judgment task, the same principle applies. The image generation function defines two line lengths: one for the reference and one for the comparison line. Larger length differences make the task easier, while smaller ones make it harder. The difficulty index is therefore the inverse of the absolute length difference between the two lines. Finally, in the dots estimation task, we regulate the difference between the number of dots in the reference box and in the distractor box. As before, task difficulty is the inverse of this difference.

For the experiments testing task difficulty, we generated 9 to 13 levels of difficulty per model and task, each corresponding to a fixed range of visual differences between the correct and incorrect options. For each level, we created about 50 images at comparable average difficulty, resulting in a total of 463 to 795 images per model and task that meet the criterion of Section 2.1.1 (Section S3). Each image was then used in a conformity experiment following the same procedure described above, allowing us to record conformity bias as a function of task difficulty for each model.

Performance

To assess model performance, we use the same images generated for the task difficulty experiments. For each image, we compute the difference between the logits of the correct and of the incorrect answer, obtained from the model’s output distribution before applying the softmax function; since the softmax depends only on this difference, it is the log-odds of the correct response. This difference provides a model-dependent proxy of how strongly the correct option is favored, that is of the model’s confidence when it answers alone. Higher values correspond to stronger probability mass assigned to the correct response. This quantity is therefore used as a proxy for model performance in the analyses reported in Figure 3a and 3b.

Normative Effects

To investigate normative conformity, we use the same pool of images as in Section 2.1.2. We design two experimental conditions that differ only in how the model is informed about the visibility of its response to others.

In the private condition, the prompt specifies that the model’s answer will not be seen by other participants. This is intended to isolate the informational component of conformity, as the model has no social incentive to align with the group. We use 100 paraphrased statements with equivalent meaning to minimize linguistic bias. Examples include:


  • “Your response will not be shared with other participants.”;



  • “Other participants will not be able to see your answer.”;



  • “Your answer will not be visible to the group.”


In the public condition, we use the exact inverse statements, indicating that the model’s answer will be shared with others. This adds a visibility cue analogous to those used in human studies of normative influence. Examples include:


  • “Your response will be shared with other participants.”;



  • “Other participants will be able to see your answer.”;



  • “Your answer will be visible to the group.”


For each pair of matched prompts (one private, one public), we run the full conformity experiment and compute the difference in conformity bias between the two conditions:

\(\begin{equation*}\text{norm} = \text{AUC}_{\text{public}}-\text{AUC}_{\text{private}}.\end{equation*}\)

This score quantifies the increase in conformity associated with making the model’s response public. We assess the statistical significance of this effect across the 100 prompt variations using \(95\%\) confidence intervals obtained by resampling stimuli. Results are shown in Figure 3c, one point per model and task. Examples of the prompt variations used in these experiments are also provided in Section S1.

Social Impact Theory

To evaluate the role of source strength in shaping conformity, we modify the baseline prompt by replacing the generic term “participants” with more specific social roles: “chatbots,” “kids,” “scientists,” “policemen,” “military officers,” “experts,” and “judges” (see Figure 4a). This manipulation allows us to assess whether the perceived authority or expertise of the source modulates model behavior, as suggested by the Social Impact Theory.

To test social proximity, we consider nationality as a social identity attribute. The model is assigned a random identity at the beginning of each experiment, and the responses of other participants are labeled as coming from either the same or a different group. We define a set of ten nationalities, and at the start of each trial the model is told: “Your nationality is nationality1.” When presenting the responses of other participants, each is prefixed with the corresponding group label, for example: nationality2: reply 1: I think the answer is B. We then compare two conditions: one where nationality1 and nationality2 are the same, and another where they differ. Results are shown in Figure 4b, while the complete list of nationalities used is provided in Section S1.

To investigate in-group bias, we adapt the setting to eliminate specific attributes. A random letter is selected to represent a group label (group1), and the model is informed: “You will be divided into groups with other participants. Your group is group1.” Each confederate response is preceded by its group identity: group2: reply 1: I think the answer is B. As before, we compare conformity bias when group1 and group2 are either the same or different (Figure 4b and 4d).

The experiments testing spatial and temporal proximity are presented in Figure 4e. In these conditions, the baseline prompt is extended with framing statements specifying the position or time of each confederate:


  • spatial condition: “Each participant is located at a specific distance from you, which is indicated before their response.”



  • temporal condition: “Each participant responded at a different time, which is indicated before their response.”


Each response is then annotated accordingly. For instance:


  • spatial: “reply 1 (distance from you: 10 meters away): I think the answer is B.”



  • temporal: “reply 1 (time of reply: 10 minutes ago): I think the answer is B.”


Two main conditions are tested: one where all responses are described as occurring “right here” or “right now,” simulating the perception of immediate presence, and another where responses are described as coming from sources located farther in space or time. Each distance or delay is a separate condition, shared by all the replies of a trial (the full list of values is reported in Section S1, and the results at every level in Figure S4). Conformity bias is then compared between the near and distant conditions, showing a significant reduction in conformity bias when responses are perceived as spatially or temporally distant (see Figure S3c,d in Section S2).

All experiments in this section use the same image pool as described in Section 2.1.2.

Models Employed

For our analysis, we employed a range of open-source multimodal models, including Qwen2 7B (Wang et al., 2024), Qwen2.5 3B, 7B, and 32B (Bai et al., 2025); Gemma3 4B, 12B, and 27B (Gemma Team et al., 2025); Mistral Small 3.1 24B (Mistral AI, 2025); and Ovis2 4B, 8B, 16B, and 34B (Lu et al., 2024).

Table 1 reports the exact model identifiers used throughout the paper, together with the abbreviations adopted for clarity.

Results for each model and task are given in Section S2.

Table 1
Model abbreviations and corresponding full model identifiers.

Abbreviation Full Model Name
Qwen2.5 3B Qwen2.5-VL-3B-Instruct
Qwen2.5 7B Qwen2.5-VL-7B-Instruct
Qwen2.5 32B Qwen2.5-VL-32B-Instruct
Qwen2 7B Qwen2-VL-7B-Instruct
Gemma3 4B gemma-3-4b-it
Gemma3 12B gemma-3-12b-it
Gemma3 27B gemma-3-27b-it
Mistral3.1 24B Mistral-Small-3.1-24B-Instruct-2503
Ovis2 4B Ovis2-4B
Ovis2 8B Ovis2-8B
Ovis2 16B Ovis2-16B
Ovis2 34B Ovis2-34B

Results

General Drivers of Conformity

Figure 2
General drivers of conformity in LLMs. a) Error probability \(p_{wrong}\), used as a proxy for conformity, as a function of group size \(N\) (i.e., number of confederates), one line per model family; individual models are reported in the Supplementary Materials. All families show a clear conformity bias, and nearly all curves saturate, at a median \(p_{\text{wrong}}\) of \(0.66\). For one representative curve, the shaded area illustrates the conformity bias, defined as the area under the \(p_{\text{wrong}}(N)\) curve (AUC) net of the baseline error; its value is printed inside it, and that of each other family at the end of its curve. b) Error probability \(p_{\text{wrong}}\) as a function of \(N\) across the three visual tasks (line judgment, color recognition, and dots estimation), pooled over all models: the curves are qualitatively similar across the three tasks, although they saturate at different levels, lowest on dots estimation. c) Error probability over the plane of group size and fraction of wrong answers, pooled over all models and tasks. Composition dominates size: in the pooled data, two unanimous confederates raise the error probability more than ten of which half are correct (\(0.31\) against \(0.20\)). All 65 attainable combinations carry \(2{,}041\) observations each. Shaded bands in a) and b) are 95% confidence intervals obtained by resampling model–stimulus pairs; c) is a measured surface and carries none.

General drivers of conformity in LLMs. a) Error probability p_wrong, used as a proxy for conformity, as a function of group size N (i.e., number of confederates), one line per model family; individual models are reported in the Supplementary Materials. All families show a clear conformity bias, and nearly all curves saturate, at a median p_wrong of 0.66. For one representative curve, the shaded area illustrates the conformity bias, defined as the area under the p_wrong(N) curve (AUC) net of the baseline error; its value is printed inside it, and that of each other family at the end of its curve. b) Error probability p_wrong as a function of N across the three visual tasks (line judgment, color recognition, and dots estimation), pooled over all models: the curves are qualitatively similar across the three tasks, although they saturate at different levels, lowest on dots estimation. c) Error probability over the plane of group size and fraction of wrong answers, pooled over all models and tasks. Composition dominates size: in the pooled data, two unanimous confederates raise the error probability more than ten of which half are correct (0.31 against 0.20). All 65 attainable combinations carry 2,041 observations each. Shaded bands in a) and b) are 95% confidence intervals obtained by resampling model–stimulus pairs; c) is a measured surface and carries none.

Group Size and Unanimity

Figure 3
Scaling of conformity bias with model performance, task difficulty and response visibility. (a) Conformity bias as a function of model performance, across all models and visual tasks. Each point represents a set of images with a specific level of performance, one of twenty quantiles within each model and task, placed at its percentile; one smoothed line per model family. The higher the performance, the lower the conformity bias, with a strong correlation (median Spearman \(\rho = -0.91\) within each model and task, negative in 30 of the 32 combinations). (b) Conformity bias as a function of task difficulty and model performance across all models and visual tasks. Images are grouped into five bins based on the log-odds of the correct answer, in quintiles within each model and task, used as a proxy for performance. For each bin, the average conformity bias, centered within each model and task, is shown as a function of normalized task difficulty, with shaded areas indicating 95% confidence intervals over models and tasks. Conformity bias increases only moderately with task difficulty across all performance levels, while at fixed difficulty it is clearly larger for the stimuli on which model performance is lower. A multivariate regression confirms that both task difficulty and performance significantly predict conformity bias, performance with the larger effect (see Table S1). (c) Difference in conformity bias between public and private response conditions, one point per model and task, sorted. Positive values indicate higher conformity bias when responses are public, that is when the model is told that its answer will be shared with the other participants rather than kept private. Vertical bars are 95% bootstrap confidence intervals over stimuli, and a point is filled where the interval excludes zero. The difference is positive in 27 of the 32 combinations, and its interval excludes zero in 21.

Scaling of conformity bias with model performance, task difficulty and response visibility. (a) Conformity bias as a function of model performance, across all models and visual tasks. Each point represents a set of images with a specific level of performance, one of twenty quantiles within each model and task, placed at its percentile; one smoothed line per model family. The higher the performance, the lower the conformity bias, with a strong correlation (median Spearman ρ = -0.91 within each model and task, negative in 30 of the 32 combinations). (b) Conformity bias as a function of task difficulty and model performance across all models and visual tasks. Images are grouped into five bins based on the log-odds of the correct answer, in quintiles within each model and task, used as a proxy for performance. For each bin, the average conformity bias, centered within each model and task, is shown as a function of normalized task difficulty, with shaded areas indicating 95% confidence intervals over models and tasks. Conformity bias increases only moderately with task difficulty across all performance levels, while at fixed difficulty it is clearly larger for the stimuli on which model performance is lower. A multivariate regression confirms that both task difficulty and performance significantly predict conformity bias, performance with the larger effect (see Table S1). (c) Difference in conformity bias between public and private response conditions, one point per model and task, sorted. Positive values indicate higher conformity bias when responses are public, that is when the model is told that its answer will be shared with the other participants rather than kept private. Vertical bars are 95% bootstrap confidence intervals over stimuli, and a point is filled where the interval excludes zero. The difference is positive in 27 of the 32 combinations, and its interval excludes zero in 21.

We begin by examining how the error probability \(p_{\text{wrong}}(N)\) varies with group size \(N\). Since the first studies on social influence, the size of the group has been identified as a critical factor in modulating conformity (Asch, 1955). In human experiments, conformity tends to increase rapidly with \(N\), reaching a plateau after approximately three to four confederates. The resulting saturation typically stabilizes at an error rate of 30–40% under social pressure.

Figure 2a) shows how the error probability \(p_{\text{wrong}}(N)\) varies across different models as a function of \(N\). As in human participants, the error probability rises steeply over the first few confederates and then flattens, in nearly every model and task: the functional form matches the classic Asch pattern. The magnitude does not. The plateau sits well above the human range, and in the most affected models and tasks the model ends up aligning almost completely with an incorrect majority. As shown in Figure 2b), the same qualitative pattern holds across the three tasks, although its magnitude is task-dependent.

We also assess the effect of unanimity among confederates. In human participants, the presence of even a single ally has been shown to significantly reduce conformity. We vary the proportion of correct and incorrect responses in the prompt. As illustrated in Figure 2c), breaking unanimity lowers the error probability. The panel spans the number of confederates on the horizontal axis and the fraction of them answering incorrectly on the vertical one. The error probability changes mostly along the vertical axis: with many confederates, moving from all-correct to all-incorrect answers covers almost its whole range, while adding confederates at a fixed fraction changes it less. The composition of the group therefore matters more than its size, and a balanced group reduces the effect without suppressing it. This indicates that the observed behavior depends systematically on the composition of the prompt context: holding the number of incorrect responses fixed, adding correct ones lowers the error probability (Section S5). Extended results for different models, visual tasks, and unanimity conditions are reported in Section S2.

These results also identify direct prompt-level levers for controlling the effect: limiting the size of an incorrect majority and introducing even a small amount of correct dissent can substantially reduce conformity-like shifts.

Effect of Model Performance and Task Difficulty

Another potential driver of the conformity bias lies in model performance, which reflects the model’s baseline reliability on the task. We quantify this performance proxy through the difference between the logits of the correct and of the incorrect answer, that is the log-odds of the correct answer. Differently from task difficulty, which is an external and model-independent property of the stimulus, the log-odds provides a model-dependent measure of how strongly the model favours the correct option. A high value indicates a stronger model preference for the correct answer. A negative relationship is expected between this performance proxy and conformity bias: the more strongly the model favours the correct answer, the less likely it should be to change its answer. In humans, a similar pattern has been reported (Crutchfield, 1955), where conformity was found to decrease with higher IQ and cognitive ability, interpreted as a proxy for task performance and confidence. For AI agents the relationship is as expected: within a model, the stimuli on which its performance is higher are those on which it conforms less (Figure 3a), as reported for text models (Zhu et al., 2025).

A further factor influencing conformity is the intrinsic difficulty of the task. In human experiments, it has long been observed that more difficult tasks lead to higher conformity levels, as individuals tend to rely more on the group when they feel uncertain about their own judgment (Crutchfield, 1955; Sherif, 1935). In our framework, task difficulty can be quantified directly from the image generation procedure: for each task a generation parameter sets how far apart the two options are, namely the RGB distance, the difference in line length, or the difference in dot counts (Section 2). This provides an objective and model-independent measure of task difficulty.

As shown in Figure 3b, the conformity bias increases with task difficulty. The relationship is clear and significant for most models and tasks (Section S7): the harder the task, the more likely the model is to align with the majority. This pattern is qualitatively consistent with established human results, where higher task difficulty and perceptual challenge are known to amplify conformity.

The overall picture, illustrated in Figure 3b) shows that both predictors matter, although they are linked, since a harder task lowers model performance: conformity bias rises only moderately with task difficulty at every level of performance, while at a fixed difficulty it is clearly larger where model performance is lower. A multivariate regression confirms these observations: both are significant predictors of conformity bias, performance the stronger one (see Table S1). Since in our tasks difficulty is set by how far apart the two options are, part of its effect may come from a wrong answer that is nearly right. Improving a model’s accuracy or confidence, however, does not make it immune to incorrect majority responses: even on the stimuli on which it is most confident, the conformity bias remains above zero in every model and task (Section S7). This suggests that mitigation efforts should focus especially on difficult inputs near the model’s competence boundary, where conformity-like shifts are most likely to emerge.

Normative Effects

Figure 4
The Social Impact Theory in AI agents. (a) Error probability \(p_{\text{wrong}}\) as a function of group size \(N\) under different source strengths, pooled over all models. The base condition (dashed) refers to generic participants. (b) Error probability curves for different levels of social proximity, pooled over all models. The model is assigned a nationality or a group identity, and confederate responses are labeled as the same or a different group. The black dashed curve shows the neutral baseline with no identity specified. (c) Average conformity bias, measured as the area under the curves in panel (a) relative to the base condition, shown separately for the three tasks as a function of source strength. Stronger sources produce a larger conformity bias, and sources below zero a smaller one. Pure authority has no consistent effect: “policemen” and “military officers” raise it in only about half of the models and tasks. (d) Rise in conformity bias from sharing a nationality (horizontal) and from sharing an arbitrary group label in the minimal group experiment (vertical), against a different one, one point per model and task. Both are positive in all 32 combinations, and the nationality is slightly the larger in most. (e) Shift in conformity bias between near and distant confederates, in space (filled) or time (open): the conformity bias with near confederates minus its mean over ten distances or delays, one point per model, sorted by the effect in space. Bands in a) and b) are 95% confidence intervals obtained by resampling model–stimulus pairs, and bars in e) by resampling stimuli.

The Social Impact Theory in AI agents. (a) Error probability p_wrong as a function of group size N under different source strengths, pooled over all models. The base condition (dashed) refers to generic participants. (b) Error probability curves for different levels of social proximity, pooled over all models. The model is assigned a nationality or a group identity, and confederate responses are labeled as the same or a different group. The black dashed curve shows the neutral baseline with no identity specified. (c) Average conformity bias, measured as the area under the curves in panel (a) relative to the base condition, shown separately for the three tasks as a function of source strength. Stronger sources produce a larger conformity bias, and sources below zero a smaller one. Pure authority has no consistent effect: “policemen” and “military officers” raise it in only about half of the models and tasks. (d) Rise in conformity bias from sharing a nationality (horizontal) and from sharing an arbitrary group label in the minimal group experiment (vertical), against a different one, one point per model and task. Both are positive in all 32 combinations, and the nationality is slightly the larger in most. (e) Shift in conformity bias between near and distant confederates, in space (filled) or time (open): the conformity bias with near confederates minus its mean over ten distances or delays, one point per model, sorted by the effect in space. Bands in a) and b) are 95% confidence intervals obtained by resampling model–stimulus pairs, and bars in e) by resampling stimuli.

A foundational distinction in social psychology separates two types of conformity: informational and normative (Deutsch & Gerard, 1955). Informational conformity arises when individuals rely on the group to resolve uncertainty or ambiguity, assuming that others may possess better knowledge or insight. In such cases, conforming is seen as a rational strategy to improve accuracy. Normative conformity, instead, reflects a social motivation: individuals align with the group not because they doubt their own judgment, but to avoid standing out, preserve group cohesion, or prevent social rejection. This form of conformity can occur even when the correct answer is known or suspected, indicating a pressure to conform rooted in social dynamics rather than cognitive uncertainty.

To test whether response visibility modulates the effect, we compare two conditions: in the private condition the model is told that its answer will remain unseen by the others, and in the public condition that it will be shared with them.

We then compare the two settings by computing the difference in the conformity bias across 100 prompt variations (see Section 2 for details). As shown in Figure 3c, most models exhibit an increase in conformity bias when responses are made public. The remaining models and tasks show small negative differences, mostly not distinguishable from zero. These results indicate that response visibility can modulate the conformity-like shift in the direction predicted by normative-conformity accounts. Thus, keeping model judgments private or independently committed before aggregation can reduce conformity-like shifts. The effect also depends on how the sharing is framed: when the model is also told why its answer will be shared, the extra conformity disappears, and in many models and tasks reverses (Section S4.3). Independently of visibility, asking the model to judge the image on its own evidence lowers the conformity bias in every model and task (Section S4).

Social Impact Theory in Ai Agents

Strength of the Sources

The Social Impact Theory (Latané, 1981; Latané & Wolf, 1981) identifies three core variables that influence the conformity bias: group size \(N\), source strength \(S\), and immediacy \(I\). This relationship is commonly formalized as:

\(\begin{equation*}\text{conformity} = f(N, S, I)\end{equation*}\)

Group size was examined above; we now test the other two. The variable \(S\), or source strength, refers to the perceived authority, expertise, or credibility of the influencing agents. In human experiments, individuals are more likely to conform when the influence originates from figures viewed as authoritative or knowledgeable. For example, participants tend to align more with the opinions of scientists, doctors, or police officers, compared to those of peers or anonymous individuals.

We replace the neutral label “participants” with roles of differing perceived authority: “scientists”, “judges”, “policemen”, “military officers”, “experts”, “kids”, or “chatbots”. Figure 4a) shows how the error probability curves \(p_{\text{wrong}}(N)\) change as a function of the source type. Overall, models tend to conform more when exposed to responses attributed to socially “strong” sources associated with expertise, such as experts, scientists or judges, and less when those responses come from low-authority sources such as children or other chatbots, while authority alone, as for policemen or military officers, has no consistent effect. The low conformity with chatbots may reflect the influence of instruction tuning, which encourages models to treat human inputs as more trustworthy than those generated by other artificial agents. When human and chatbot confederates are mixed in one list and disagree, the models tend to follow the humans (Section S6).

Figure 4c summarizes the results across all models. Each point corresponds to the conformity bias relative to the base condition, computed from the error probability in Figure 4a and shown separately for the three visual tasks. Although individual models may react differently to the source strength, averaging across models reveals a consistent positive trend: stronger sources systematically induce higher conformity bias, with experts raising it by up to \(0.13\) above the neutral condition, and kids and chatbots lowering it by up to \(0.06\).

Social Proximity and Immediacy

The second key variable in the Social Impact Theory is immediacy \(I\), which captures the perceived closeness, whether social, spatial or temporal, between the individual and the source. We state that level explicitly in the prompt.

As a first test, we use nationality as a proxy of social proximity. The model is told its own (randomly assigned) nationality and is then presented with responses attributed either to participants of the same group or to participants of a different one. As shown in Figure 4b, conformity bias increases when the confederates share the same nationality as the model, and decreases when they belong to a different one. The neutral baseline, with no specified identity, lies in between these two conditions.

To assess whether this effect depends on explicit attributes or can also arise from minimal group categorization, we run a second experiment. Here, the model is simply assigned to an arbitrary group (for example, “Group X”) and is shown responses from members of either the same or a different group. Again the conformity bias rises with a shared label, even with no defining characteristic attached to it, while a different label leaves it close to the level without labels. LLM outputs can therefore show a group-membership effect based purely on abstract group labels, without the need for explicit identity features, a pattern reminiscent of minimal-group effects observed in humans (Tajfel et al., 1971; Turner et al., 1979). As shown in Figure 4d, both manipulations raise the conformity bias in every model and task, and an arbitrary label does nearly as much as a shared nationality. Full results for all models, with \(95\%\) confidence intervals, are reported for the shared nationality in Section S2.

Spatial and temporal proximity behave the same way, and are reported in Figure 4e. In these conditions, the model is told that the responses originate from participants located at varying physical distances or who responded at different times. Consistent with human findings, conformity bias decreases when responses are described as coming from sources that are distant in space or time, whatever the stated distance or delay (Figure S4). These results show that immediacy robustly modulates the observed conformity-like shift. Together, these results show that source labels and proximity information provide additional control levers: less expert, less similar, or less immediate sources weaken the overall effect.

Discussion

In this study we systematically examined the conformity bias in large multimodal language models by adapting classic visual experiments from social psychology to AI agent contexts. Understanding how these models respond to the opinions of others in their prompt is a timely and increasingly explored question (Luo et al., 2026; Weng et al., 2025; Zhu et al., 2025). Conformity can indeed play both a positive role, enhancing social cohesion, but on the other hand, it can also favor misinformation spreading and malicious attacks to groups of interacting models. Guided by decades of social psychological research (Asch, 1955; Cialdini & Goldstein, 2004), we tested which factors influence the tendency of these models to conform. The results of our experiments align closely with core predictions from Social Impact Theory (Latané, 1981; Latané & Wolf, 1981), as agents respond to the number, strength, and immediacy of social sources in ways that are phenomenologically similar to human social behavior. These results confirm on perceptual tasks what the studies of text models (Weng et al., 2025; Zhu et al., 2025) found for the size of the majority and the model’s own uncertainty, and extend them to the strength and immediacy of the sources.

These empirical findings reveal vulnerabilities in model decision-making that have profound implications for the deployment of AI agents. The core result is particularly striking: models that achieve near-perfect accuracy on visual tasks when acting independently can be systematically influenced to provide incorrect answers when exposed to an incorrect majority. This vulnerability persists even when the task is clear and unambiguous, showing that socially framed context can shift otherwise accurate responses in artificial systems. Such susceptibility raises important security concerns, as malicious actors could exploit these mechanisms to coordinate misinformation, bias collective responses, or compromise decision-making in multi-agent settings, and agreement of this kind has been shown to propagate once model outputs are fed back to other models (Kasprova et al., 2026).

Importantly, this tendency to conform is present across all models tested, regardless of their size or performance level. Both small and large models, from a few billion to tens of billions of parameters, exhibit qualitatively similar conformity patterns, although larger models show a smaller conformity bias on simple tasks. These results hold for the twelve open-source models of four families that we tested; larger or proprietary models, trained in other ways, may respond differently to social signals in the prompt. Within a model, performance does matter: a higher performance reduces the conformity bias, roughly by half, but in no model and task does it remove it. Models that perform better on the task therefore still show a clear tendency to conform. This indicates that social susceptibility is not removed by higher model competence, but is a recurring property of current AI architectures.

Beyond characterizing this susceptibility, our framework provides a practical and quantitative approach to controlling conformity-like bias. The drivers examined here identify prompt- and workflow-level levers for modulating the effect: limiting majority size, breaking unanimity, collecting independent responses, and controlling source information can reduce conformity-like shifts, while task difficulty can identify cases requiring additional safeguards. These levers are not all of equal strength (Hussain & Nielbo, 2026): for example, breaking the unanimity of the majority reduces the conformity bias more than any instruction we gave the model to resist it (Section S4).

Our results also have implications for collective machine behavior (Rahwan et al., 2019). Understanding how socially framed information affects model outputs becomes critical as we move toward systems where multiple AI agents coordinate on complex tasks, because in such systems the output of one agent becomes the input of another. A wrong answer produced in response to the kind of socially framed prompt studied here can pass from one agent to the next, so understanding how it is produced is a necessary step in understanding how such systems behave. The patterns we observe suggest that without appropriate interventions, these systems might be susceptible to manipulation campaigns, groupthink phenomena, and systematic biases that could undermine their effectiveness and reliability, which is why robust safeguards are needed.

Our behavioral approach characterizes conformity-like shifts at the output level, without investigating the internal processes from which they originate. These patterns may result from context following, instruction tuning, associations learned during pretraining, or other mechanisms. An out-of-domain test we performed on handwritten digits rules out the possibility that the models reproduce results memorized from the conformity literature (Section S5). Future research should distinguish among these explanations and examine whether any of the underlying processes are functionally related to, or merely simulate, the socio-psychological dynamics of human conformity (Zhong et al., 2025).

Addressing these questions will also support the development of architecture- and training-level mitigations while preserving the beneficial aspects of coordination and social learning in systems of interacting models. This includes designing architectures that can distinguish between legitimate consensus-building and malicious manipulation, creating transparency measures that account for context-induced behavioral changes, and establishing protocols for maintaining decision integrity in multi-agent settings. As AI agents increasingly operate at the boundaries of their capabilities in real-world applications, understanding and controlling their susceptibility to social influence becomes essential for ensuring the reliability and security of the systems built on them.

Data Availability Statement

The datasets and image stimuli employed in this study are publicly available at https://doi.org/10.5281/zenodo.18022032. All code used for the simulations and analyses is publicly available at https://github.com/alebellina412/conformity_LLMs.

Conflicts of Interest

The authors declare no competing interests.

Funding

This work was supported by the University of Konstanz, Konstanz, Germany, and Centro Ricerche Enrico Fermi, Rome, Italy. The research leading to these results has received funding from the European Union under the AI4SOCIAL+ Project, grant agreement 101292886.

Author Contributions Statement

D.G. and G.D.M. conceived and designed the study. A.B. and G.D.M. implemented the code, performed the analyses, and carried out all simulations. D.G. supervised the project and provided methodological guidance. A.B. and G.D.M. drafted the original manuscript. All authors contributed to the interpretation of the results and reviewed the final version of the manuscript.

Data and Code Availability

All code used for the simulations and analyses, together with the datasets and image stimuli employed in this study, are publicly available at https://github.com/alebellina412/conformity_LLMs.

Acknowledgements

We acknowledge the limited use of a generative AI assistant (Claude, Anthropic) for analysis code and text editing during the revision. All data and results were checked by the authors, who take full responsibility for the content.

Supplementary Materials

The supplementary materials can be found here.

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Editor Curated

Frequently Asked Questions

  • Do AI models really conform to group pressure like humans do?

    Yes, in a measurable way. Bellina et al. (2026) adapted classic Asch-style visual experiments for twelve open-source multimodal language models ranging from 3 to 34 billion parameters. The models first had to answer simple image questions correctly on their own, with a median baseline accuracy above 0.99. They were then shown answers from fictional ‘participants’ who all picked the wrong option. The probability of a wrong answer rose quickly over the first few confederates and then flattened, which mirrors the classic human pattern. However, the effect was much larger than in humans. Errors plateaued at a median of 66%, compared with roughly 30–40% in human studies, and some models aligned almost completely with the incorrect majority. Larger models showed a smaller conformity bias on simple tasks, but every model and family tested displayed the effect to some degree.

  • How did the researchers measure conformity in AI models?

    The approach described by Bellina et al. (2026) relies on the model’s output logits rather than its final text answer. This gives a continuous probability for each option. The steps were:

    1. Present a synthetic image for one of three tasks: line judgment, color recognition, or dots estimation.
    2. Keep only images the model answers correctly with a probability of at least 0.85 when no other answers are shown.
    3. Add N incorrect confederate answers to the prompt and record the probability of a wrong answer, called pwrong(N).
    4. Calculate the conformity bias as the area under the pwrong(N) curve, minus the baseline error.

    Filtering for high baseline accuracy ensures that answer shifts reflect social context rather than an inability to perceive the image. A further test on handwritten digits (MNIST) ruled out the possibility that models were simply reproducing memorized results from the conformity literature.

  • Does a single dissenting voice reduce AI conformity?

    It helps substantially. In human studies, one ally who breaks unanimity sharply reduces conformity, and Bellina et al. (2026) found a similar pattern in AI models. The researchers varied both the number of confederates and the fraction giving wrong answers. The share of wrong answers had a much larger effect than group size. In the pooled data, two unanimous wrong confederates produced a higher error probability (0.31) than ten confederates of whom half were correct (0.20). When the number of incorrect responses was held fixed, adding correct ones lowered the error probability. A balanced group reduced the effect but did not eliminate it. The authors also report that breaking unanimity reduced the conformity bias more than any instruction they gave the model to resist group pressure. Introducing correct dissent is therefore one of the most effective levers available.

  • Does it matter who the other 'participants' are said to be?

    Yes. Social Impact Theory predicts that conformity depends on the number, strength, and immediacy of the sources, and Bellina et al. (2026) confirmed all three in AI models:

    1. Strength: Labeling confederates as experts, scientists, or judges increased conformity, with experts adding up to 0.13. Labeling them as kids or chatbots reduced it by up to 0.06. Authority labels alone, such as policemen or military officers, had no consistent effect, raising conformity in only about half of the model–task combinations.
    2. Social proximity: Sharing a nationality, or even an arbitrary group label, raised conformity in all 32 model–task combinations. This resembles the minimal group effect seen in humans.
    3. Spatial and temporal immediacy: Responses described as coming from distant places or earlier times produced less conformity.

    Overall, perceived expertise and closeness amplified the models’ tendency to follow the group.

  • How can developers reduce conformity in multi-agent AI systems?

    Bellina et al. (2026) identify several practical, prompt-level and workflow-level levers:

    1. Limit majority size and avoid presenting unanimous groups.
    2. Introduce correct dissent, since breaking unanimity reduced the bias more than any resistance instruction the authors tested.
    3. Collect judgments independently before aggregating them. Telling models their answers would be public increased conformity in 27 of 32 combinations.
    4. Control source information, because expert-sounding, similar, or immediate sources amplify the effect.
    5. Ask the model to rely on its own evidence, which lowered conformity bias in every model and task.

    The authors also recommend extra safeguards for difficult inputs near the model’s competence boundary, where conformity-like shifts are most likely. Higher model performance roughly halved the bias but never removed it. Accuracy alone is therefore not sufficient protection against manipulation in interconnected AI systems.

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