Group size is a function of relative neocortical volume in nonhuman primates. Extrapolation from this regression equation yields a predicted group size for modern humans very similar to that of certain hunter-gatherer and traditional horticulturalist societies. Groups of similar size are also found in other large-scale forms of contemporary and historical society. Among primates, the cohesion of groups is maintained by social grooming; the time devoted to social grooming is linearly related to group (...) class='Hi'>size among the Old World monkeys and apes. To maintain the stability of the large groups characteristic of humans by grooming alone would place intolerable demands on time budgets. It is suggested that (1) the evolution of large groups in the human lineage depended on the development of a more efficient method for time-sharing the processes of social bonding and that (2) language uniquely fulfills this requirement. Data on the size of conversational and other small interacting groups of humans are in line with the predictions for the relative efficiency of conversation compared to grooming as a bonding process. Analysis of a sample of human conversations shows that about 60% of time is spent gossiping about relationships and personal experiences. It is suggested that language evolved to allow individuals to learn about the behavioural characteristics of other group members more rapidly than is possible by direct observation alone. (shrink)

This paper makes two contributions to the research on cooperation in experimental social dilemmas. First, we demonstrate an interaction between group size and communication in which the effectiveness of communication in promoting cooperation declines as group size increases. Second, we corroborate some previous research showing the positive effect of communication is due to sincere signaling of cooperative intentions. The experimental data comes from 289 undergraduate student subjects playing public goods games over a computer network. These findings (...) suggest that large group size opens up a niche for the evolution of institutions for collective action. (shrink)

How to handle orphan drugs for rare diseases is a pressing problem in current health-care. Due to the group size of patients affecting the cost of treatment, they risk being disadvantaged in relation to existing cost-effectiveness thresholds. In an article by Niklas Juth it has been argued that it is irrelevant to take indirectly operative factors like group size into account since such a compensation would risk discounting the use of cost, a relevant factor, altogether. In (...) this article we analyze Juth’s argument and observe that we already do compensate for indirectly operative factors, both outside and within cost-effectiveness evaluations, for formal equality reasons. Based on this we argue that we have reason to set cost-effectiveness thresholds to integrate equity concerns also including formal equality considerations. We find no reason not to compensate for group size to the extent we already compensate for other factors. Moreover, groups size implying a systematic disadvantage also on a global scale, i.e. taking different aspects of the health condition of patients suffering from rare diseases into account, will provide strong reason for why group size is indeed relevant to compensate for. (shrink)

Business ethics research has long examined the dichotomy between remaining silent or reporting ethical misconduct to a third party. Little is known, however, about ethical conversations within a work group after observing misconduct. Specifically, we do not know how many members of their work group individuals choose to communicate with. These conversations could have important implications for creating an ethical workplace. We propose that psychological standing is an important driver of individuals’ decisions not to remain silent and to (...) instead raise moral concerns with a greater number of others in their work group. In addition, integrating existing work on structural power, psychological standing, and the bystander effect, we develop a moderated mediation model with both structural power position and work group size as contextual drivers of psychological standing. Our model is supported across four studies using different designs and methodological approaches. Our results contribute to the understanding of when and why individuals raise moral concerns, and they provide insights into how an ethical context is created in organizations. (shrink)

Social data mining has become an emerging area of research in information and communication technology fields. The scope of social data mining has expanded significantly in the recent years with the advance of telecommunication technologies and the rapidly increasing accessibility of computing resources and mobile devices. People increasingly engage in and rely on phone communications for both personal and business purposes. Hence, mobile phones become an indispensable part of life for many people. In this article, we perform social data mining (...) on mobile social networking by presenting a simple but efficient method to define social closeness and social grouping, which are then used to identify social sizes and scaling ratio of close to “8”. We conclude that social mobile network is a subset of the face-to-face social network, and both groupings are not necessary the same, hence the scaling ratios are distinct. Mobile social data mining. (shrink)

Phenomena like meat sharing in hunter-gatherers, self-sacrifice in intergroup conflicts, and voluntary contribution to public goods provision in laboratory experiments have led to the development of numerous theories on the evolution of altruistic in-group beneficial behavior in humans. Many of these theories abstract away from the effects of kinship on the incentives for public goods provision, though. Here, it is investigated analytically how genetic relatedness changes the incentive structure of that paradigmatic game which is conventionally used to model and (...) experimentally investigate collective action problems: the linear public goods game. Using recent anthropological data sets on relatedness in 61 contemporary hunter-gatherer and horticulturalist societies the relevant parameters of this model are then estimated. It turns out that the kinship patterns observed in these societies substantially reduce the negative effect of increasing group size on incentives for public goods provision. It is suggested, therefore, that renewed attention should be given to inclusive fitness theory in the context of public goods provision also in sizable groups, because its explanatory power with respect to this central problem in the evolution of human cooperativeness and altruism might have been substantially underrated. (shrink)

Data from various settings suggest that there is an upper limit of about four on the number of individuals who can interact in spontaneous conversation. This limit appears to be a consequence of the mechanisms of speech production and detection. There appear to be no differences between men and women in this respect, other than those introduced by women’s lighter voices.

To date researchers planning experiments have always lived by the mantra that 'using equal sample sizes gives the best results' and although unequal groups are also used in experimentation, it is not the preferred method of many and indeed actively discouraged in literature. However, during live study planning there are other considerations that we must take into account such as availability of study participants, statistical power and, indeed, the cost of the study. These can all make allocating equal sample sizes (...) difficult, and sometimes near impossible. This, some might say, means that the study would not adhere to rigorous statistical standard (Rosenbaum and Rubin, 1985). However, here we present evidence that, not only is this a false assumption, but that we may actually gain more power in the study by actually using unequal groups. Here, data from a Sepsis Biomarker study is used, in which the aim is to predict, by biomarker level and presence, whether the patient would go on to develop sepsis. It was found that larger control groups may give more power to studies looking for an effect in the mid range but not for large or small effects. This study shows merit in the hypothesis that more power can be achieved when a larger control group is used. Published by the Ministry of Defence at dstl - Reference DSTLTR92592 P2PP2R-2016-02-23T13:39:45. (shrink)

This paper examines social network size in contemporary Western society based on the exchange of Christmas cards. Maximum network size averaged 153.5 individuals, with a mean network size of 124.9 for those individuals explicitly contacted; these values are remarkably close to the group size of 150 predicted for humans on the basis of the size of their neocortex. Age, household type, and the relationship to the individual influence network structure, although the proportion of kin (...) remained relatively constant at around 21%. Frequency of contact between network members was primarily determined by two classes of variable: passive factors (distance, work colleague, overseas) and active factors (emotional closeness, genetic relatedness). Controlling for the influence of passive factors on contact rates allowed the hierarchical structure of human social groups to be delimited. These findings suggest that there may be cognitive constraints on network size. (shrink)

Science and technology policy is often confronted with issues that are both complex and controversial and which have to be decided upon in a delicate constellation of policy-makers, experts, stakeholders, non-governmental organizations and the public. One attempt to deal with such a complex problem is via citizen involvement. Participatory technology assessment (pTA) already goes back to several decades, and countries have made various experiences. While in some countries, governments established technology assessment organizations, which also included pTA in their methodological portfolio, (...) others primarily rely on experts to make decisions on science and technology policy. In a third group of countries non-state actors, such as social scientists, experimented with pTA. However, they were often unable to link these experiments to policy-making. This paper deals with the question of why this variation exists and compares the use of pTA in Switzerland and Austria. Despite similarities between the two countries, both had quite different experiences with pTA so far. Whereas several pTAs have been carried out in Switzerland until today, Austrian pTAs have remained infrequent. The aim of this paper is to explain this difference as a result of different ways of policy-making which affect the use and chances of pTA. (shrink)

Hyperlink cinema is an emergent film genre that seeks to push the boundaries of the medium in order to mirror contemporary life in the globalized community. Films in the genre thus create an interacting network across space and time in such a way as to suggest that people’s lives can intersect on scales that would not have been possible without modern technologies of travel and communication. This allows us to test the hypothesis that new kinds of media might permit us (...) to break through the natural cognitive constraints that limit the number and quality of social relationships we can manage in the conventional face-to-face world. We used network analysis to test this hypothesis with data from 12 hyperlink films, using 10 motion pictures from a more conventional film genre as a control. We found few differences between hyperlink cinema films and the control genre, and few differences between hyperlink cinema films and either the real world or classical drama (e.g., Shakespeare’s plays). Conversation group size seems to be especially resilient to alteration. It seems that, despite many efficiency advantages, modern media are unable to circumvent the constraints imposed by our evolved psychology. (shrink)

In Grooming, Gossip and the Evolution of Language, Robin Dunbar argues that speech developed from primate vocalizations as a replacement for grooming. Dunbar convincingly shows that language is just a highly developed form of primate communication. But Dunbar's thesis about the relationship between speech and optimal group size is problematic: his focus on strong ties leads him to overlook the integrative force of weak‐tie networks.

In my target article, I argued (1) that the relationship between neocortical size and group size in primates implies that there is a cognitive limit on the size of human groups, and (2) that time constraints forced the evolution of language as a more efficient means of bonding the large groups that humans evolved. The doubts about these claims raised by these additional commentaries largely reflect misinterpretation of my original claims.

Sex dimorphism occurs when group means differ by four or more standard deviations. However, the average size of the corpus callosum is greater in males by about one standard deviation in rats, 0.2 standard deviation in humans, and virtually zero in mice. Furthermore, variations in corpus callosum size are related to brain size and are not sex specific.

Human cooperation is highly unusual. We live in large groups composed mostly of non-relatives. Evolutionists have proposed a number of explanations for this pattern, including cultural group selection and extensions of more general processes such as reciprocity, kin selection, and multi-level selection acting on genes. Evolutionary processes are consilient; they affect several different empirical domains, such as patterns of behavior and the proximal drivers of that behavior. In this target article, we sketch the evidence from five domains that bear (...) on the explanatory adequacy of cultural group selection and competing hypotheses to explain human cooperation. Does cultural transmission constitute an inheritance system that can evolve in a Darwinian fashion? Are the norms that underpin institutions among the cultural traits so transmitted? Do we observe sufficient variation at the level of groups of considerable size for group selection to be a plausible process? Do human groups compete, and do success and failure in competition depend upon cultural variation? Do we observe adaptations for cooperation in humans that most plausibly arose by cultural group selection? If the answer to one of these questions is “no,” then we must look to other hypotheses. We present evidence, including quantitative evidence, that the answer to all of the questions is “yes” and argue that we must take the cultural group selection hypothesis seriously. If culturally transmitted systems of rules that limit individual deviance organize cooperation in human societies, then it is not clear that any extant alternative to cultural group selection can be a complete explanation. (shrink)

Our ability to rapidly distinguish new from already stored information is important for behavior and decision making, but the underlying processes remain unclear. Here, we tested the hypothesis that contextual cues lead to a preselection of information and, therefore, faster recognition. Specifically, on the basis of previous modeling work, we hypothesized that recognition time depends on the amount of relevant content stored in long-term memory, i.e., set size, and we explored possible age-related changes of this relationship in older humans. (...) In our paradigm, subjects learned by heart four different word lists written in different colors. On the day of testing, a color cue indicated with a probability of 50% that a subsequent word might be from the corresponding list or from a list of new words. The old/new status of the word had to be distinguished via button press. As a main finding, we can show in a sample of n = 49 subjects, including 26 younger and 23 older humans, that response times increased linearly and logarithmically as a function of set size in both age groups. Conversely, corrected hit rates decreased as a function of set size with no statistically significant differences between both age groups. As such, our findings provide empirical evidence that contextual information can lead to a preselection of relevant information stored in long-term memory to promote efficient recognition, possibly by cyclical top-down and bottom-up processing. (shrink)

We consider a proportional-prize contest to forecast future events, and show that, in equilibrium, this mechanism possesses perfect forecasting ability for any group size when the contestants share common knowledge about the probabilities by which future events realize. Data gathered in a laboratory experiment confirm the performance invariance to group size. By contrast, when realization probabilities are not common knowledge, there are some differences across group sizes. The mechanism operates marginally better with three or four (...) compared to two players. However, this effect is mainly driven by players’ behavior rather than by differences in the beliefs they form about the realization probabilities. (shrink)

Researchers have suggested that infants exhibiting baby schema are considered cute. These similar studies have mainly focused on changes in overall baby schema facial features. However, whether a change in only eye size affects the perception of cuteness across different facial expressions and ages has not been explicitly evaluated until now. In the present study, a paired comparison method and 7-point scale were used to investigate the effects of eye size on perceived cuteness across facial expressions and ages. (...) The results show that stimuli with large eyes were perceived to be cuter than both unmanipulated eyes and small eyes across all facial expressions and age groups. This suggests not only that the effect of baby schema on cuteness is based on changes in a set of features but also that eye size as an individual feature can affect the perception of cuteness. (shrink)

Choice overload is the phenomenon that increasing the number of options in an assortment makes choosing between options more difficult, sometimes leading to avoidance of making a choice. In this pre-registered online experiment, choice overload was tested in a charitable behavior context, where participants faced a monetary donation choice. Charity organization assortment size was varied between groups, ranging between 2 and 80 options. The results indicate that there were no meaningful differences in donation likelihood between the 16 organization assortment (...) sizes, neither for individuals with high preference certainty nor for individuals with uncertain preferences among charitable causes. Having more charitable organizations to choose from did not affect donation behavior. (shrink)

The topic of the article concerns the issue of place attachment and its determinants. An analysis of place attachment was performed in terms of place identity and place dependence. Moreover, links between place attachment and selected geographical, demographic and psychological variables were investigated. The study group included 759 respondents: 398 women and 361 men, aged 18-83 years, residing in 74 places in the Silesian Province, a region in Poland: in 10 sub-regions in the Upper Silesian conurbation and outside the (...) conurbation. The study used the Place Attachment Scale, the Satisfaction with Life Scale and a personal information section containing questions regarding place of permanent residence, sex and age. Results showed that subjects residing in smaller and non-industrial places had a stronger place attachment than those residing in larger and industrial cities. People living outside the Upper Silesian conurbation were more strongly attached to their place of residence in terms of place identity than those residing in the Upper Silesian conurbation. People living in the Zagłębie sub-region were more strongly attached in terms of place dependence than those residing in the Bytom sub-region. Satisfaction with life was positively correlated with place attachment. Older subjects were more strongly attached to their place of residence. Men and women did not differ in the sense of place attachment and life satisfaction. (shrink)

Proxy signature and group signature are two basic cryptographic primitives. Due to their valuable characteristics, many schemes have been put forward independently and they have been applied in many practical scenarios up to the present. However, with the development of electronic commerce, many special requirements come into being. In this article, we put forward the concept of group–proxy signature, which integrates the merits of proxy signature and group signature for the first time. We also demonstrate how to (...) apply our scheme to construct an electronic cash system. The space, time, and communication complexities of the relevant parameters and processing procedures are independent of group size. Our demonstration of the concrete group–proxy signature scheme shows that the concepts brought forward by us are sure to elicit much consideration in the future. (shrink)

Absolute and relative outcome measures measure a treatment’s effect size, purporting to inform treatment choices. I argue that absolute measures are at least as good as, if not better than, relative ones for informing rational decisions across choice scenarios. Specifically, this dominance of absolute measures holds for choices between a treatment and a control group treatment from a trial and for ones between treatments tested in different trials. This distinction has hitherto been neglected, just like the role of (...) absolute and baseline risks in rational decision-making that my analysis reveals. Recognizing both aspects advances the discussion on reporting outcome measures. (shrink)

Business groups dominate the economic landscape in many economies around the world. While business groups overcome the institutional voids arising due to inefficiencies of external markets, they also possess market power, which could be economically and socially counterproductive, especially for unaffiliated firms. Drawing on the transaction cost and industrial organization economics, we examine whether the presence of business group affiliated firms in industries restricts the entry of unaffiliated firms or firms affiliated with small- and medium-size business groups. Findings (...) based on Indian firms suggest that investments by business group affiliated firms in an industry have an inverted U-shaped relationship with the investment by unaffiliated firms. However, investments by firms affiliated with large-sized business groups have a U-shaped relationship with the investment by affiliates of small and medium business groups. These findings suggest that the market power of business groups and entry barrier relationship is contingent on the size of the business groups. (shrink)

In Group Duties, Stephanie Collins proposes a ‘tripartite’ social ontology of groups as obligation-bearers. Producing a unified theory of group obligations that reflects our messy social reality is challenging and this ‘three-sizes-fit-all’ approach promises clarity but does not always keep that promise. I suggest considering the epistemic level as primary in determining collective obligations, allowing for more fluidity than the proposed tripartite ontology of collectives, coalitions and combinations.

Although perceptual grouping has been widely studied, its mechanisms remain poorly understood. We propose a neural model of grouping that, through top-down control of its circuits, implements a grouping strategy involving both a connection strategy (which elements to connect) and a selection strategy (that defines spatiotemporal properties of a selection signal to segment target elements and facilitate identification). We apply the model to a letter discrimination task that investigated relationships among uniform connectedness and the grouping principles of proximity and shape (...) similarity. Participants reported whether small circles formed a global letter E or H, and these circles could be connected by a line or be embedded in a matrix of squares. In the model, a good grouping strategy for this task consists of a connection strategy that connects circles but not squares for all conditions and a selection strategy that uses a selection signal of varying size, depending on whether squares were present. Consistent with empirical results, which were verified in two replication studies, model performance is worse with distractor squares, and line connectors improve performance only in the condition with squares. Rather than relying on abstract grouping principles, we show how the empirical results can be explained in terms of observers implementing a task-dependent grouping strategy that promotes overall performance. (shrink)

It is generally assumed that group agency must be a social phenomenon because it involves interactions among many human beings. This assumption overlooks the real metaphysical nature of agency, which is both normative and voluntarist. Construed as a normative phenomenon, individual agency arises wherever there is a point of view from which deliberation and action proceed in accord with the requirements that define individual rationality. Such a point of view is never a metaphysical given, but is always a product (...) of rational activities that aim to satisfy the requirements that define individual rationality. When such a deliberative point of view is forged within a whole human life, there is a single agent of human size. But such points of view can also be forged within parts of human lives so as to constitute multiple agents within them; and they can also be achieved within groups of human lives so as to constitute group agents that literally deliberate and act as one. If such a group agent were a social phenomenon, then its agency would simultaneously be the agency of many even as it was also the agency of one. In that case, its deliberations and actions would have to proceed from many separate deliberative points of view, at the same time that they also proceeded from a single deliberative point of view. A correct account of rational agency shows that this is not necessarily so, and indeed, not typically so. Moreover, if it were so much as possible for this to be so, it would require special conditions of the sort that Rousseau identified in his account of the general will. But this special case is not a good model on which to understand the cases of group agency that are most often discussed in the philosophical literature. They are more appropriately viewed as cases in which the condition of individual agency is realized at the level of a group, than as cases of social agency per se. (shrink)

A significant part of responsible innovation is engagement with diverse groups of stakeholders; this remains true for projects investigating responsible innovation practices. This chapter discusses strategies for engaging small and medium-sized enterprises in co-creating visions of and plans for implementing responsible innovation, drawing on the example of engagement with United Kingdom cyber security companies. The key aspect of the engagement was building trust between the responsible innovation researchers and the companies. Trust was built by a movement away from traditional recruitment (...) procedures for research projects, towards proactive engagement with the culture and traditions of the sector – participating in company sponsored talks and conferences, finding ways to communicate effectively, and ensuring a tailored message that fit the expectations and requirements of the sector. This chapter reviews the context in which the recruitment took place, the assumptions made prior to recruitment, the approaches taken, the revisions made to these approaches, and ultimately offers some general recommendations for industry engagement in responsible innovation activities. (shrink)

The variation in genome size and basic chromosome number was analyzed in the wide range of angiosperm plants. A divergence of monocots vs. dicots (eudicots) genome size distributions was revealed. A similar divergence was found for annual vs. perennial dicots. The divergence of monocots vs. dicots genome size distributions holds at different taxonomic levels and is more pronounced for species with larger genomes. Using nested analysis of variance, it was shown that putative constraints on genome size (...) variation are not only stronger in dicots as compared to monocots but in the former they start to operate already at the family level, whereas in the latter they do so only at the order level. At the same time, variation in basic chromosome number is constrained at the order level in both groups. Higher basic chromosome numbers were found in perennial plants as compared to the annual ones, which can be explained by their need for a higher genetic recombination as compensation for the longer life-cycles. A negative correlation was found between genome size and basic chromosome number, which can be explained as a trade-off between different recombination mechanisms. (shrink)