Interpersonal violence victimisation, HIV-related behaviours and STIs among adult, urban Indigenous and non-Indigenous gay, bisexual and other men who have sex with men in Guatemala.

Gay, bisexual and other men who have sex with men are disproportionately affected by HIV in Guatemala; interpersonal violence may increase behaviours that augment the risk of HIV in this group. Although 44% of Guatemalans identify as Indigenous, little information exists on the experiences of Indigenous sexual minority individuals. In this study, we sought to compare different forms of violence and HIV-related behaviours by Indigenous identity among gay, bisexual and other men who have sex with men; and determine if associations between violence and HIV-related behaviours differed by Indigenous identity. We used cross-sectional survey data from 716 Spanish-speaking, adult men recruited from urban centres to examine the prevalence of and relationship between different forms of interpersonal violence and HIV-related behaviours using logistic regression analyses, including the moderating effect of Indigenous identity. In general, fewer Indigenous participants reported interpersonal violence victimisation and HIV-related behaviours compared to their non-Indigenous counterparts. In weighted multivariable analyses, non-Indigenous participants who reported physical and/or sexual violence were over five times as likely to report transactional sex (OR = 5.17, 95% CI 2.11-12.68, p < 0.001), but the relationship was not significant for Indigenous participants. Findings suggest that Indigenous sexual minority men have unique contexts and that additional strengths-based research is needed to ensure that actions and efforts to promote violence and HIV prevention meet their needs.

Counter-Punishment, Communication, and Cooperation among Partners.

We study how communication affects cooperation in an experimental public goods environment with punishment and counter-punishment opportunities. Participants interacted over 30 rounds in fixed groups with fixed identifiers that allowed them to trace other group members' behavior over time. The two dimensions of communication we study are asking for a specific contribution level and having to express oneself when choosing to counter-punish. We conduct four experimental treatments, all involving a contribution stage, a punishment stage, and a counter-punishment stage in each round. In the first treatment communication is not possible at any of the stages. The second treatment allows participants to ask for a contribution level at the punishment stage and in the third treatment participants are required to send a message if they decide to counter-punish. The fourth combines the two communication channels of the second and third treatments. We find that the three treatments involving communication at any of the two relevant stages lead to significantly higher contributions than the baseline treatment. We find no difference between the three treatments with communication. We also relate our results to previous results from treatments without counter-punishment opportunities and do not find that the presence of counter-punishment leads to lower cooperation level. The overall pattern of results shows that given fixed identifiers the key factor is the presence of communication. Whenever communication is possible contributions and earnings are higher than when it is not, regardless of counter-punishment opportunities.

Punish and voice: punishment enhances cooperation when combined with norm-signalling.

Material punishment has been suggested to play a key role in sustaining human cooperation. Experimental findings, however, show that inflicting mere material costs does not always increase cooperation and may even have detrimental effects. Indeed, ethnographic evidence suggests that the most typical punishing strategies in human ecologies (e.g., gossip, derision, blame and criticism) naturally combine normative information with material punishment. Using laboratory experiments with humans, we show that the interaction of norm communication and material punishment leads to higher and more stable cooperation at a lower cost for the group than when used separately. In this work, we argue and provide experimental evidence that successful human cooperation is the outcome of the interaction between instrumental decision-making and the norm psychology humans are provided with. Norm psychology is a cognitive machinery to detect and reason upon norms that is characterized by a salience mechanism devoted to track how much a norm is prominent within a group. We test our hypothesis both in the laboratory and with an agent-based model. The agent-based model incorporates fundamental aspects of norm psychology absent from previous work. The combination of these methods allows us to provide an explanation for the proximate mechanisms behind the observed cooperative behaviour. The consistency between the two sources of data supports our hypothesis that cooperation is a product of norm psychology solicited by norm-signalling and coercive devices.