A Theory of Bayesian Groups

A group is often construed as one agent with its own probabilistic beliefs (credences), which are obtained by aggregating those of the individuals, for instance through averaging. In their celebrated “Groupthink”, Russell et al. (2015) require group credences to undergo Bayesian revision whenever new information is learnt, i.e., whenever individual credences undergo Bayesian revision based on this information. To obtain a fully Bayesian group, one should often extend this requirement to non‐public or even private information (learnt by not all or just one individual), or to non‐representable information (not representable by any event in the domain where credences are held). I propose a taxonomy of six types of ‘group Bayesianism’. They differ in the information for which Bayesian revision of group credences is required: public representable information, private representable information, public non‐representable information, etc. Six corresponding theorems establish how individual credences must (not) be aggregated to ensure group Bayesianism of any type, respectively. Aggregating through standard averaging is never permitted; instead, different forms of geometric averaging must be used. One theorem—that for public representable information—is essentially Russell et al.'s central result (with minor corrections). Another theorem—that for public non‐representable information—fills a gap in the theory of externally Bayesian opinion pooling.     

Religion and Esotericism among Students: A Cross-Cultural Comparative Study

Analysing the results of a study on religious and esoteric beliefs and practice among university students from five European and five American countries, we found that the level of religiousness of students depends very much on their cultural environment: the level of religiosity and esoteric beliefs is significantly higher among North- and South-American students than among European students. On the other hand, Asian spiritual techniques and esoteric methods of healing are practised more frequently by students in North-Western European countries. In the second part of the paper, we examine the relationship between academic discipline and religious worldviews. According to our data, students in the social sciences and the arts are more distanced from religion than students of other areas of science, but they, like students of medicine and languages, are closer to esotericism than students of the 'exact sciences'. Several hypotheses are proposed to explain these results.     

Psychopathy and Anxiety in Children and Adolescents: New Insights on Developmental Pathways to Offending

This study examined the relation between psychopathy and anxiety in 130 juvenile offenders. Adolescents were administered three psychopathy scales (PCL-YV, APSD, and SRP-II), a measure of psychopathology (APS), and subsequently followed prospectively in the community for three years in order to track recidivism. Three mediational models were tested to determine whether psychopathy mediates the relation between anxiety (trait anxiety, fearlessness, and trauma) and future offending. Findings indicated that psychopathy mediated the relation between two types of anxiety (trait anxiety and fearlessness) and recidivism when using the PCL-YV as an index for psychopathy. These influences were not supported when using self-report measures of psychopathy (APSD and SRP-II) and the meditational models did not apply to the anxiety subtype of trauma for any of the psychopathy measures. The PCL-YV mediational models provide new insights on the relation between psychopathy anxiety and offending. Specifically, pathways from fearlessness to psychopathy and later offending were in the expected direction. Surprisingly, higher levels of trait anxiety were linked with higher levels of psychopathy and subsequent offending. This developmental difference is in contrast with theory and the adult literature on this topic. The results from the current study suggest that both fear and anxiety may be important considerations in treatment planning for the reduction of adolescent offending.     

The Consistency Argument for Ranking Functions

The paper provides an argument for the thesis that an agent’s degrees of disbelief should obey the ranking calculus. This Consistency Argument is based on the Consistency Theorem. The latter says that an agent’s belief set is and will always be consistent and deductively closed iff her degrees of entrenchment satisfy the ranking axioms and are updated according to the ranktheoretic update rules. Special Issue Formal Epistemology I. Edited by Branden Fitelson     

Race,Religion and Support for the Affordable Care Act

Review of Religious Research - Using Pew Research Center’s Voter Attitudes Survey from 2012, we assess the impact race has on the relationship between religious faith and worship attendance...     

Physical,verbal, and relational forms of bullying among German students: age trends,gender differences,and correlates

A revised version of the Bully/Victim Questionnaire [Olweus, 1991] was given to 2,086 fifth–tenth grader students from schools in two German federal states. The results were analysed in terms of frequencies of self‐reports of different forms of bullying (physical, verbal, relational/indirect; for bullies and for victims), gender and grade differences. Overall, 12.1% of the students reported bullying others and 11.1% reported being bullied (victimisation). We classified 2.3% of the students as bully/victims due to their self‐report. Significantly more boys reported bullying others, regardless of bullying form, and significantly more boys than girls were classified as bully/victims. Although there was no gender difference for victimisation at all, boys reported significantly more often than girls being bullied physically. Besides, self‐reports of pure and overlapping forms of bullying behaviour (relational, verbal, physical) were analysed. With regard to age trends, students from middle grades reported the highest rates of bullying. Self‐reported rates of victimisation were higher for younger students, regardless of form of victimisation. Furthermore, class size was not linked to reports of bullying and victimisation. Results from logistic regression analyses emphasised that the variables “gender” and “grade” add significantly to the prediction of self‐reported bullying; “grade” and variables measuring impaired psychosocial “well‐being” of students at school (e.g., feeling of not being popular, negative attitude towards breaks) add significantly to the prediction of self‐reported victimisation. The results are discussed against the background of other study findings, accentuating the significance of gender‐ and age‐specific forms of bullying/victimisation. Aggr. Behav. 32:1–15, 2006. © 2006 Wiley‐Liss, Inc.