DOI: 10.11583/dtu.25943116.v1
title: Data for: Investigating the impact of background noise on collaborative decision-making using an individual-weighted voting model (2026)

description: The data included in this dataset are the estimated weights and summary statistics as described in the accompanying paper*. The raw confidence judgment data used in the study can be found in a separate dataset (doi.org/10.11583/DTU.25163816). See also the related paper** for additional analysis and dissemination of the data. For questions or inquiries, please contact Ingvi Örnólfsson (rinor@dtu.dk, ORCID: 0000-0002-2222-0739)* Örnólfsson et al. (2026): Investigating the impact of background noise on collaborative decision-making using an individual-weighted voting model, doi.org/10.1186/s41235-026-00710-4** Örnólfsson et al. (2024): The Effect of Collaborative Triadic Conversations in Noise on Decision-Making in a General-Knowledge Task, doi.org/10.1177/23312165241305058---------------------------------------------------------------------------------------------This study investigated how background noise influenced group decision-making in triadic interactions. Ten triads of normal-hearing participants were recruited. Initially, each participant responded to a series of binary general knowledge questions and provided a confidence rating along with their response. Subsequently, the questions were discussed in groups of three in two distinct conditions; a high-intensity background noise condition (78 dB, referred to as the ‘noisy’ condition’) or a low-intensity condition (48dB, referred to as the ‘quiet’ condition). Finally, participants individually answered the same questions again.The study comprised 30 participants organized into groups of ten triads. All participants, aged between 20 and 35 years, were native Danish speakers with self-reported normal-hearing status. Except for two pairs, participants were unfamiliar with each other prior to the experiment. The experiment was conducted in Danish and took approximately 2.5 hours.The participants were seated in an equilateral triangle configuration, facing the other two group members, as illustrated in Figure 1b. The distance between participants was approximately 1.5 m. They wore eye-tracking glasses capturing point-of-view footage, eye-gaze data, and pupil dilation. Additionally, three microphones were utilized, including a pair of in-ear binaural microphones and a cheek-mounted microphone; however, data from these devices were not analyzed in this study.The group was surrounded by eight loudspeakers (Dynaudio BM6P), arranged in a ring of radius 2.4 m. Each loudspeaker played a separate Danish monologue (Ahrens & Lund, 2022), resulting in a spatially distributed multi-talker masker. The monologues lasted approximately 90 seconds each and were looped for the duration of the conversation. The loudspeakers were driven by a sonible d:24 amplifier. The masker was presented at sound pressure levels (SPLs) of either 48 dB or 78 dB, corresponding to the quiet and the noisy condition, respectively. The simultaneous presentation of multiple masking speech sources rendered them individually unintelligible in both conditions. To eliminate visual distractions, a circular black curtain entirely enclosed the participant area.The initial task for the participants involved responding individually to a series of binary general-knowledge questions categorized into three topics: Hollywood movies (identifying the oldest of two movies), Copenhagen landmarks (determining which of two locations is closest to the city center), and European countries (determining which of two countries has the most inhabitants). Each topic comprised two lists of 28 questions, one for each acoustic noise condition. Consequently, each list contained 28 trials, formulated by employing all unique binary questions from the eight items associated with that topic (e.g., eight Hollywood movies). Before the primary experiment, the group underwent a brief trial round on a different topic not used in the study. This allowed participants to familiarize themselves with the task, the technical interface, and with each other, thus overcoming any initial awkwardness in their conversations.Questions were presented on a touch-screen tablet, showing a visual illustration of the two options along with accompanying labels. The participants were instructed to select an option and provide a confidence level, expressed as a percentage between 50% and 100%, with 50% indicating no preference for either option, while 100% meant absolute certainty in the decision (Figure 1a). They were asked to interpret the scale as indicating their estimated probability of having answered the question correctly, i.e. a metacognitive judgment.After the initial set of 28 questions, a conversation round followed, during which the participants discussed their answers with the other group members. Collaborative problem-solving was encouraged, emphasizing the importance of improving the performance of all group members, not just oneself. Each participant was given a sheet displaying the eight items from the preceding question round during the conversation (see Figure 1b). Once a 10-minute time limit was reached or the conversation concluded naturally, participants individually answered the same 28 questions again (see Figure 1c). This process was repeated six times, once for each of the three topics and in each of the two noise conditions. The order of topics and conditions was randomized between groups, ensuring that the same topic did not appear consecutively. A brief break was incorporated after the third question round.