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Cited by 396Distributed Control Multi-Agent SystemsEvacuation and Crowd DynamicsOpinion Dynamics and Social Influence

Leadership, consensus decision making and collective behaviour in humans

Open access
Dyer, John R.G, Johansson, Anders, Helbing, Dirk, Couzin, Iain D, Krause, Jens·2009·Philosophical Transactions of the Royal Society B: Biological Sciences
DOI 10.1098/rstb.2008.0233PMC PMC2689712
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Abstract

This paper reviews the literature on leadership in vertebrate groups, including recent work on human groups, before presenting the results of three new experiments looking at leadership and decision making in small and large human groups. In experiment 1, we find that both group size and the presence of uninformed individuals can affect the speed with which small human groups (eight people) decide between two opposing directional preferences and the likelihood of the group splitting. In experiment 2, we show that the spatial positioning of informed individuals within small human groups (10 people) can affect the speed and accuracy of group motion. We find that having a mixture of leaders positioned in the centre and on the edge of a group increases the speed and accuracy with which the group reaches their target. In experiment 3, we use large human crowds (100 and 200 people) to demonstrate that the trends observed from earlier work using small human groups can be applied to larger crowds. We find that only a small minority of informed individuals is needed to guide a large uninformed group. These studies build upon important theoretical and empirical work on leadership and decision making in animal groups.

AI snapshot

Written from the paper’s full text.

TL;DR

This paper reviews leadership in vertebrate groups and presents three human group experiments showing that uninformed individuals, leader spatial positioning, and a small informed minority shape consensus movement decisions. The results extend small-group findings to large crowds, though the large-crowd work is largely anecdotal.

Key findings

  • Experiment 1 (22 mixed-sex groups of eight) found that groups with uninformed individuals took significantly longer to reach the periphery than groups in the 2 versus 2 or 4 versus 4 treatments (GLMM: F2,42=12.417, p<0.0001), with no significant difference between 2 versus 2 and 4 versus 4. Group splitting also differed by treatment (F2,42=15.604, p<0.0001): 4 versus 4 groups split more than uninformed-present or 2 versus 2 groups; 9/13 splits (69%) in 4 versus 4 were into two groups of four, while 5/7 splits (71%) in the uninformed-present treatment were into groups of six and two. Deviation from target did not differ significantly (F2,42=0.0583, p=0.944), with most groups scoring no deviation (19/22, 20/22, and 21/22 across treatments).
  • Experiment 2 (15 mixed-sex groups of ten) found that spatial positioning of informed individuals affected speed and accuracy. Time to periphery differed by treatment (F3,42=3.712, p=0.0186), with one informed individual in the core and one on the periphery reaching the perimeter significantly faster than two core leaders or two leaders on opposite sides. Deviation from target also differed (F3,42=3.798, p=0.0170), with the mixed core/periphery treatment deviating significantly less than all other treatments.
  • Experiment 3 used large crowds of 100 and 200 people. At least 5% of group members had to be informed to lead the group with reasonable effectiveness (90% of the group) to the target; with 10% informed, the whole group reached the target without a split. In a 20 versus 10 conflict, the majority initially moved toward the 20-informed target, but after about 110 s the 10 informed individuals also reached their target and took at least 40% of the group with them, leaving a bridge and oscillation between targets. With no informed individuals, the group formed a torus after approximately 30 s, ranging between 14 and 17 m in diameter.

Methods

  • The paper first reviews literature on leadership in vertebrate groups, then reports three new experiments. Experiment 1 took place February–March 2006 at the University of Leeds and University of Wales at Bangor with 22 mixed-sex groups of eight undergraduate students in a 10 m circular arena with targets 1–16. Treatments were 2 versus 2 (group size 4), uninformed present (two informed plus four uninformed, group size 8), and 4 versus 4 (group size 8); participants could not talk or gesture, and experiments were double-blind.
  • Experiment 2 took place January 2006–March 2007 at Leeds and Bangor with 15 mixed-sex groups of ten undergraduate students in the same arena setup. Four treatments varied the starting positions of two informed individuals with the same target direction: mixed (one core, one periphery), close (both periphery), far (opposite periphery), and 2 core.
  • Experiment 3 took place 4 March 2007 in Cologne and 5 May 2007 in Freiburg with volunteers aged 18–70 in a 50 m circular arena with targets 1–12. A single group of 200 was tested in five treatments (20 leaders, five leaders, 10 leaders, no informed control, and 20 versus 10 conflict); the uninformed and 10-leader treatments were repeated with a group of 100. Statistical analyses for experiments 1 and 2 used generalized linear mixed models in R v. 2.5.1 with quasi-Poisson or binomial error distributions and FDR correction for pairwise comparisons.

Limitations

  • The paper states that experiment 3 yields mainly anecdotal evidence because of a small sample size consisting in part of a single group of 200 people and, for some treatments, an additional group of 100 people, due to logistical difficulties in testing such large groups. It also states that the arena was not large enough to decide whether the conflict group would have reached the majority-preferred target cohesively or split.
  • Evident from the text: experiments 1 and 2 used undergraduate students, and experiment 3 used volunteers responding to TV or radio advertisements, so the samples may not represent broader populations. The no-talking/no-gesture protocol was designed to minimize active information transfer and may not capture all real-world human group decision making.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1098/rstb.2008.0233

Cites

Statistics

Nothing to recompute.

Claims the paper makes

0 of 43 cited sources checked · 0 supported · 0 flagged

  • Findingown data
    § Abstract

    In experiment 2, having a mixture of leaders positioned in the centre and on the edge of a group increases the accuracy with which the group reaches their target.

    “We find that having a mixture of leaders positioned in the centre and on the edge of a group increases the speed and accuracy with which the group reaches their target.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Participants in experiments 1 and 2 followed the standard instructions and their individual behavioural rules (e.g., walked at normal speed, stayed within arm's length, did not talk or gesture, and attempted to reach their assigned target).
  • Findingown data
    § Abstract

    In experiment 1, the presence of uninformed individuals affects the likelihood of the group splitting.

    “In experiment 1, we find that both group size and the presence of uninformed individuals can affect the speed with which small human groups (eight people) decide between two opposing directional preferences and the likelihood of the group splitting.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Participants in experiments 1 and 2 followed the standard instructions and their individual behavioural rules (e.g., walked at normal speed, stayed within arm's length, did not talk or gesture, and attempted to reach their assigned target).
  • Findingown data
    § Abstract

    In experiment 3, only a small minority of informed individuals is needed to guide a large uninformed group.

    “We find that only a small minority of informed individuals is needed to guide a large uninformed group.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Participants in experiments 1 and 2 followed the standard instructions and their individual behavioural rules (e.g., walked at normal speed, stayed within arm's length, did not talk or gesture, and attempted to reach their assigned target).
  • Findingown data
    § Abstract

    In experiment 2, having a mixture of leaders positioned in the centre and on the edge of a group increases the speed with which the group reaches their target.

    “We find that having a mixture of leaders positioned in the centre and on the edge of a group increases the speed and accuracy with which the group reaches their target.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Participants in experiments 1 and 2 followed the standard instructions and their individual behavioural rules (e.g., walked at normal speed, stayed within arm's length, did not talk or gesture, and attempted to reach their assigned target).
  • Findingown data
    § Abstract

    In experiment 2, the spatial positioning of informed individuals within small human groups (10 people) affects the speed of group motion.

    “In experiment 2, we show that the spatial positioning of informed individuals within small human groups (10 people) can affect the speed and accuracy of group motion.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Participants in experiments 1 and 2 followed the standard instructions and their individual behavioural rules (e.g., walked at normal speed, stayed within arm's length, did not talk or gesture, and attempted to reach their assigned target).
  • May combine two claims. 16
  • Classified as probably not a substantial claim. 34

  • May combine two claims.

    Findingown data
    § 3. Results

    The torus formed after approximately 30 s and ranged between 14 and 17 m in diameter.

    “The torus formed after approximately 30 s and ranged between 14 and 17 m in diameter (figure 4a).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § 3. Results

    A bridge of people remained between the two targets with a constant oscillation of people between the two targets.

    “A bridge of people remained between the two targets with a constant oscillation of people between the two targets (see appendix 2 in the electronic supplementary material).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data
    § 3. Results

    The torus was not stationary and moved position within the arena.

    “The torus was not stationary and moved position within the arena (figure 4b).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § 3. Results

    After approximately 110 s the 10 informed individuals had also reached their target and managed to take at least 40 per cent of the group with them.

    “After approximately 110 s the 10 informed individuals had also reached their target and managed to take at least 40 per cent of the group with them.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § 3. Results

    Most groups were highly accurate, finishing at their targets and scoring no deviation: 19/22 groups in the 2 versus 2 treatment, 20/22 in the uninformed treatment, and 21/22 in the 4 versus 4 treatment.

    “Most groups were highly accurate, finishing at their targets and therefore scoring no deviation (19/22 groups in the 2 versus 2 treatment, 20/22 groups in the uninformed treatment and 21/22 groups in the 4 versus 4 treatment).”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Premisecitation
    § 1. Introduction

    When individual differences are large (more than 120°), the group decides in favour of one set of informed individuals.

    “However, when individual differences are large (more than 120°) then the group decides in favour of one set of informed individuals.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Couzin et al. (2005)

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    Premisecitation
    § 1. Introduction

    The Couzin et al. (2005) model predicts that a small proportion of informed individuals (approx. 5% of group members) can accurately guide an uninformed group.

    “Couzin et al. (2005) predicted that a small proportion of informed individuals (approx. 5% of group members) can accurately guide an uninformed group and that for any given group size the accuracy of group motion increases as the proportion of informed individuals is increased.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Couzin et al. (2005)

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    Premisecitation
    § 1. Introduction

    For any given group size, the accuracy of group motion increases as the proportion of informed individuals is increased.

    “Couzin et al. (2005) predicted that a small proportion of informed individuals (approx. 5% of group members) can accurately guide an uninformed group and that for any given group size the accuracy of group motion increases as the proportion of informed individuals is increased.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Couzin et al. (2005)

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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation
    § 1. Introduction

    Consensus decisions are important for both animal and human groups because they allow groups to remain together despite individual differences in preference and help prevent individuals from losing the benefits associated with being part of a large group.

    “They are very important for both animal and human groups as they allow groups to remain together despite individual differences in preference and consequently help prevent individuals from losing the benefits associated with being part of a large group (Conradt & Roper 2009; Sumpter & Pratt 2009).”
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    • cites Conradt & Roper 2009

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    • cites Sumpter & Pratt 2009

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    Premisecitation
    § 1. Introduction

    Where there are conflicts in the preferences of informed individuals and the number of individuals with each preference is unequal, the group will always go with the majority of informed individuals.

    “Furthermore, they predict that where there are conflicts in the preferences of informed individuals and the number of individuals with each preference is unequal, the group will always go with the majority of informed individuals.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Couzin et al. (2005)

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    Premisecitation
    § 1. Introduction

    Leadership behaviour has been found in a number of vertebrate species across a range of taxa.

    “Evidence of leadership behaviour has been found in a number of vertebrate species across a range of taxa, including ungulates (Leicester sheep, Ovis aries; Squires & Daws 1975; sable antelope, Hippotragus niger: Stine et al. 1982; Charolais heifers, Bos taurus; Dumont et al. 2005; zebras, Equus burchellii: Fischhoff et al. 2007), primates (gorillas, Gorilla gorilla beringei: Fossey 1972; chimpanze”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Squires & Daws 1975

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    • cites Stine et al. 1982

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    • cites Dumont et al. 2005

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    Premisecitation
    § 1. Introduction

    A small minority of informed golden shiners (Notemigonus crysoleucas) could guide uninformed conspecifics from a preferred area of a tank to a less preferred brightly lit area where food was expected.

    “Similarly, Reebs (2000, 2001) found that a small minority of informed fish (golden shiners N. crysoleucas) could guide uninformed conspecifics from a preferred area of a tank, to a less preferred brightly lit area where food was expected.”
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    • cites Reebs (2000, 2001)

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    Premisecitation
    § 1. Introduction

    When the number of informed individuals with each preference is equal, the group averages over the preferences if the differences are small (less than 120°).

    “When the number with each preference is equal, the group averages over the preferences if the differences are small (less than 120°).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Couzin et al. (2005)

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    Premisecitation
    § 1. Introduction

    Four demonstrator guppies (Poecilia reticulata) could guide four uninformed conspecifics through a hole to escape an oncoming trawl net.

    “Reader et al. (2003) demonstrated that four demonstrator guppies, Poecilia reticulata, could guide four uninformed conspecifics through a hole to escape an oncoming trawl net.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Reader et al. (2003)

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    Premisecitation
    § 1. Introduction

    Front positions in fish shoals tend to be occupied by larger fish and food-deprived fish.

    “Krause et al. (1998) found that front positions tended to be occupied by larger fish and food-deprived fish.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Krause et al. (1998)

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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation
    § 1. Introduction

    In other vertebrate species, leadership can be more variable and there is no correlation with dominance.

    “In other species, it has been demonstrated that leadership can be more variable and that there is no correlation with dominance (bar-headed geese A. indicus: Lamprecht 1992; zebra finches T. guttata: Beauchamp 2000; white-faced capuchins Cebus capucinus: Leca et al. 2003).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Lamprecht 1992

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    • cites Beauchamp 2000

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    • cites Leca et al. 2003

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    Premisecitation
    § 1. Introduction

    A single individual in a front position could have a strong influence on an entire shoal of 16 roach (Rutilus rutilus).

    “Bumann et al. (1997) showed that individuals in front positions in shoals of roach R. rutilus led the group, finding that just a single individual in a front position could have a strong influence on an entire shoal of 16 fish.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Bumann et al. (1997)

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    Premisecitation
    § 1. Introduction

    Large knowledgeable fish are readily followed by small uninformed fish, whereas small knowledgeable fish are less readily followed by larger individuals.

    “Reebs (2001) also found an influence of body size on leadership with large knowledgeable fish being readily followed by small uninformed fish whereas small knowledgeable fish were less readily followed by larger individuals.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Reebs (2001)

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    Premisecitation
    § 1. Introduction

    In some vertebrate species, groups tend to be led by dominant individuals.

    “In some species, it has been shown that groups tend to be led by dominant individuals (gorillas G. g. beringei: Fossey 1972; Leicester sheep, Squires & Daws 1975; chimpanzees P. troglodytes: Wilson 1980; sable antelope H. niger: Stine et al. 1982; bush dogs S. venaticus: Macdonald 1996; wolves C. lupus: Peterson et al. 2002).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Fossey 1972

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    • cites Squires & Daws 1975

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    • cites Wilson 1980

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    Study design and conductcitation
    § 2. Material and methods

    Where a significant effect of treatment was found from a GLMM, pairwise comparisons were made between the treatments by correcting the alpha level using an FDR correction.

    “Where a significant effect of treatment was found from a GLMM, pairwise comparisons were made between the treatments by correcting the alpha level using an FDR correction (see Benjamini & Hochberg 1995).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Benjamini & Hochberg 1995 source

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    Study design and conductnone given
    § 2. Material and methods

    In experiment 2, treatment orders were systematically rotated to minimize any order effects.

    “Treatment orders were systematically rotated to minimize any order effects.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning
    § 2. Material and methods

    Experiment 3 will yield mainly anecdotal evidence because it is based on a small sample size consisting of, in part, a single group of 200 people, and in other parts, an additional group of 100 people.

    “This experiment will yield mainly anecdotal evidence as it is based on a small sample size consisting of, in part, a single group of 200 people, and in other parts, an additional group of 100 people.”
    Quote in the paperNot a substantial claim

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    Study design and conductreasoning
    § 2. Material and methods

    In experiment 3, the procedure ensured that whatever colour hats the informed individuals were wearing they were spread out among the group.

    “This ensured that whatever colour hats the informed individuals were wearing they were spread out among the group.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Study design and conductnone given
    § 2. Material and methods

    All p-values from pairwise tests throughout the paper were ranked and the lowest p-value was compared with an alpha level of 0.00278 (0.05/no. of pairwise comparisons).

    “All p-values from pairwise tests throughout the paper were ranked and the lowest p-value was compared with an alpha level of 0.00278 (0.05/no. of pairwise comparisons).”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data
    § 2. Material and methods

    In all cases, time and deviation data were overdispersed and quasi-Poisson error distributions were found to be the best fit to the data.

    “In all cases, time and deviation data were overdispersed and quasi-Poisson error distributions were found to be the best fit to the data.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductnone given
    § 2. Material and methods

    All experiments in experiments 1 and 2 were carried out double-blind: both the participants and the individuals who measured the response variables were not aware of the purpose of the experiment.

    “All experiments were carried out double-blind in that both the participants and the individuals who measured the response variables were not aware of the purpose of the experiment.”
    • Also stated in: § 2. Material and methods · plain
      “All experiments were carried out double-blind in that both the participants and the individuals who measured the response variables were not aware of the purpose of the experiment.”
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    Premisecitation
    § 4. Discussion

    Kerth et al. (2006) found that the temporary splitting of groups could allow individuals to avoid following majority decisions that did not favour them.

    “They also found that the temporary splitting of groups could allow individuals to avoid following majority decisions that did not favour them.”
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    • cites Kerth et al. (2006)

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    Interpretationown data
    § 4. Discussion

    By increasing group size we also increase the likelihood of group fragmentation, but only if the additional group members are informed individuals.

    “This suggests that by increasing group size we also increase the likelihood of group fragmentation, but only if the additional group members are informed individuals (significantly more groups split in the 4 versus 4 than the 2 versus 2 treatment).”
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    Premisecitation
    § 2. Material and methods

    Previously informed individuals have been shown by Dyer et al. (2008) not to affect the results of subsequent trials.

    “Previously informed individuals have been shown by Dyer et al. (2008) not to affect the results of subsequent trials, but we also test for their effects here.”
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    • cites Dyer et al. (2008)

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    Study design and conductreasoning
    § 2. Material and methods

    Group ID was entered as the random factor in each model due to the repeated-measures design of the study.

    “Group ID was entered as the random factor in each model due to the repeated-measures design of the study (each group was tested in each treatment).”
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    Premisecitation
    § 4. Discussion

    Kerth et al. (2006) found that Bechstein's bats, Myotis bechsteinii, can make group roost decisions that follow a majority rule.

    “Kerth et al. (2006) found that Bechstein's bats, Myotis bechsteinii, can make group roost decisions that follow a majority rule.”
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    • cites Kerth et al. (2006)

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    Study design and conductreasoning
    § 2. Material and methods

    In experiment 3, after each treatment, all individuals wearing the colour of hat worn by the informed individuals were removed and replaced by 20 more participants wearing the same coloured hats, so that no individuals who were previously informed would be uninformed in a subsequent trial.

    “After each treatment, all individuals wearing the colour of hat worn by the informed individuals were removed from the group and replaced by 20 more participants wearing the same coloured hats. This was done in order that no individuals who were previously informed would be uninformed individuals in a subsequent trial.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given
    § 2. Material and methods

    In experiment 1, treatment order was systematically rotated to minimize its effect on the results.

    “Treatment order was systematically rotated to minimize its effect on the results.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation
    § 4. Discussion

    Biro et al. (2006) provided further support for Couzin et al. (2005), finding that when differences between the directional preferences of two homing pigeons were small, they would average over these preferences, but when differences were large, one of the birds would become leader.

    “Biro et al. (2006) provided further support for Couzin et al. (2005); finding that when differences between the directional preferences of two homing pigeons were small, they would average over these preferences, but when differences were large, one of the birds would become leader.”
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    • cites Biro et al. (2006)

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    • cites Couzin et al. (2005)

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    Study design and conductown data
    § 3. Results

    The results in Experiment 3 are largely anecdotal because they are based on a small sample size (one group of 200 people and for some treatments a further group of 100 people) due to logistical difficulties in testing such large groups.

    “The results presented in this section are largely anecdotal as they are based on a small sample size (one group of 200 people and for some treatments a further group of 100 people) due to the logistical difficulties in testing such large groups of people.”
    Quote in the paperNot a substantial claim

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    Interpretationnone given
    § 4. Discussion

    The leader on the periphery is likely to be more mobile and unconstrained and can move freely around the outside of the group and quickly find and align with the target.

    “The leader on the periphery is likely to be more mobile and unconstrained and can move freely around the outside of the group and quickly find and align with the target,”
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    Interpretationreasoning
    § 4. Discussion

    In migrating groups of birds, more accurate navigation of the route may be expected if the experienced older individuals, who have already completed the migration in past years, are spread out through the flock.

    “For example, in migrating groups of birds, we may expect more accurate navigation of the route if the experienced older individuals, who have already completed the migration in past years, are spread out through the flock.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationreasoning
    § 4. Discussion

    This potentially sheds interesting light on torus formation in animal groups where the behaviour is frequently found in pelagic fish species such as barracuda, Sphyraena barracuda and jack, Trachurus symmetricus, and has also been described for wrinkle-lipped bats, Chaerephon plicata.

    “This potentially sheds interesting light on torus formation in animal groups where the behaviour is frequently found in pelagic fish species such as barracuda, Sphyraena barracuda and jack, Trachurus symmetricus, and has also been described for wrinkle-lipped bats, Chaerephon plicata (Siemers & Nill 2001).”
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    • cites Siemers & Nill 2001

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    Premisecitation
    § 4. Discussion

    Maransky & Bildstein (2001) found that in mixed-age flocks of broad-winged hawks, Buteo platypterus, adults were more likely (but not always) the lead bird and were more likely to be (but were not always) in the lead half of the flock.

    “One such study by Maransky & Bildstein (2001) found that in mixed-age flocks of broad-winged hawks, Buteo platypterus, adults were more likely (but not always) the lead bird and were more likely to be (but were not always) in the lead half of the flock.”
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    • cites Maransky & Bildstein (2001)

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    Interpretationown data
    § 4. Discussion

    Although there are clear differences between the study and real evacuation situations, the results may offer insight into considerations on the best places to position officials/marshals in order to evacuate people most efficiently.

    “Although there are obviously clear differences between our study and real evacuation situations where there could be widespread panic and more erratic behaviour, our results may offer some insight into considerations on the best places to position officials/marshals in order to evacuate people most efficiently.”
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    Study design and conductnone given
    § 4. Discussion

    The arena was not large enough to decide whether the group would have reached the majority preferred target cohesively, or split.

    “However, the arena was not large enough to decide whether the group would have reached the majority preferred target cohesively, or split.”
    Quote in the paperNot a substantial claim
41 of 41

  • The paper relies on this without support.

    Participants in experiments 1 and 2 followed the standard instructions and their individual behavioural rules (e.g., walked at normal speed, stayed within arm's length, did not talk or gesture, and attempted to reach their assigned target).

    “Each group was given the following standard set of instructions: ‘when we tell you to begin you should start walking at a normal speed and do not stop before being told to do so. You can walk anywhere inside or outside the circle but you have to stay within an arm's length of another individual and you should not talk or gesture to each other.’”
    “Behavioural rule 1 gave instructions to simply ‘stay with the group’, resulting in uninformed individuals. Behavioural rule 2 gave instructions to ‘Go to number X, without leaving the group’ creating informed individuals (X represents a randomly chosen number on the outer circle between 1 and 16).”

  • The paper relies on this without support.

    The observers' judgments of when a group member came within 50 cm of the perimeter were accurate.

    “After we signalled the start of a trial, it lasted until any member of the group came within 50 cm of the perimeter of the circle. This was judged by two observers on either side of the arena who were blind to the purpose of the experiment.”

  • The paper relies on this without support.

    Participants in experiment 3 followed the standardized instructions and their individual behavioural rules.

    “The participants were then read the same set of standardized instructions as in experiments 1 and 2, and normal walking speed and staying together as a group were demonstrated to them.”
    “Uninformed individuals were told to ‘Stay with the group’. Informed individuals (leaders) were told to ‘Go to 9 o'clock, but do not leave the group’.”

  • The paper relies on this without support.

    Few empirical studies on vertebrate groups outside the social science literature on human groups have looked at decision making in conflict situations.

    “To our knowledge, few empirical studies on vertebrate groups outside the social science literature on human groups have looked at decision making in conflict situations.”
4 of 4

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Unconfident people tend to increase their own confidence after interacting with a very confident person, creating a basin of attraction around that person's opinion.

    “Second, unconfident people tend to increase their own confidence after interacting with a very confident person, creating a basin of attraction around that person’s opinion [38], [39].”

    From Social Influence and the Collective Dynamics of Opinion Formation (2013) · cites this paper as [39]

The citation lists haven’t been fetched yet

References 39 · Cited by 396

Research works printed but not linked: 3

  1. Alerstam T Bird migration. 1990 Cambridge UK:Cambridge University Press.
  2. Dyer J. R. G. 2008 Leadership decision making and collective behaviour in animal groups. PhD thesis University of Leeds UK.
  3. Wilson E.O Sociobiology. 1980 Cambridge MA:Belknap Press.

Authors
Dyer, J. R. G., Johansson, A., Helbing, D., Couzin, I. D., & Krause, J.
Affiliations
  • University of Leeds (GB)
  • ETH Zurich (CH)
  • Princeton University (US)
Corresponding author
Dyer, John R.G
ORCID
Venue
Philosophical Transactions of the Royal Society B: Biological Sciences
Publisher
The Royal Society
Published
2008-12-12
Volume
364
Issue
1518
Pages
781-789
ISSN
  • 0962-8436 (ISSN-L)
  • 1471-2970
DOI
10.1098/rstb.2008.0233
PMC
PMC2689712
OpenAlex
W2162981429
Cited by
396
References
39
Citations by year
2026: 17 · 2025: 10 · 2024: 17 · 2023: 11 · 2022: 16 · 2021: 19 · 2020: 52 · 2019: 23 · 2018: 19 · 2017: 18 · 2016: 22 · 2015: 20 · 2014: 32 · 2013: 22 · 2012: 40
FWCI
5.67
Type
journal article
Language
en
Open access
Licence
royalsociety.org/journals/ethics-policies/data-sharing-mining/ (tdm)
Locations
  • Philosophical Transactions of the Royal Society B Biological Sciences (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • UCL Discovery (University College London) (submittedVersion)
  • MPG.PuRe (Max Planck Society) (submittedVersion)
  • Explore Bristol Research (submittedVersion)
  • Bristol Research (University of Bristol) (submittedVersion)
Funders
  • Engineering and Physical Sciences Research Council (GR/T11241/01)
  • Natural Environment Research Council (NE/D011035/1)
Topics
  • Physical Sciences › Computer Science › Computer Networks and Communications › Distributed Control Multi-Agent Systems
  • Physical Sciences › Engineering › Ocean Engineering › Evacuation and Crowd Dynamics
  • Physical Sciences › Physics and Astronomy › Statistical and Nonlinear Physics › Opinion Dynamics and Social Influence
Keywords
leadership, consensus building, collective behavior, human groups, group size, group fragmentation, collective motion, spatial positioning, crowds
MeSH terms
Decision Making, Humans, Leadership, Social Behavior, Consensus

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Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

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