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The research domain on the Quality of Experience (QoE) of 2Dvideo streaming has been well established. However, a new videoformat is emerging and gaining popularity and availability: VR 360-degree video. The processing and transmission of 360-degree videosbrings along new challenges such as large bandwidth requirementsand the occurrence of different distortions. The viewing experienceis also substantially different from 2D video, it offers moreinteractive freedom on the viewing angle but can also be moredemanding and cause cybersickness. Further research on the QoEof 360-videos specifically is thus required. The goal of this study isto complement earlier research by (Tran, Ngoc, Pham, Jung, andThank, 2017) testing the effects of quality degradation, freezing, andcontent on the QoE of 360-videos. Data will be gathered throughsubjective tests where participants watch degraded versions of 360-videos through an HMD. After each video they will answerquestions regarding their quality perception, experience, perceptualload, and cybersickness. Results of the first part show overall ratherlow QoE ratings and it decreases even more as quality is degradedand freezing events are added. Cyber sickness was found not to bean issue.

Objective: In a longitudinal field study, we investigated the predictive associations between six aberrant personality tendencies (schizotypal, avoidant, borderline, antisocial, narcissistic, obsessive‐compulsive) and academic success of science, technology, engineering, and mathematics students. Method: Bachelor students of Industrial Engineering at a Dutch technical university (N = 432, Mage = 18.45; 87.3% male) filled out the NEO‐PI‐R and aberrant tendencies were operationalized by the five‐factor model (FFM) compound technique. Indicators of academic achievement (grades) and persistence (credit points earned per year, re‐enrollment, study duration) were made available by the academic office. Results: Validities across the 3 years of the study program consistently support the role of two aberrant tendencies: Individuals with high antisocial tendency reached lower academic achievement, took longer to finish their study, and had a higher risk of dropout. The obsessive‐compulsive tendency was associated with higher grade‐point average, faster study progress, and higher retention rates and effects were still visible while controlling for known predictors (high school grades, Conscientiousness). Contrary to our expectations, we found no evidence for inverted U‐shaped relationships. Conclusions: We used the compound technique for aberrant tendencies based on the FFM in the academic context and our findings support the importance of personality‐based psychopathological tendencies for academic success.

Antitrust authorities all over the world are keen on the presence of a particularly aggressive competitor, a “maverick”. Yet there is a lack of theoretical justification. One plausible determinant of acting as a maverick is behavioral: the maverick derives utility from acting competitively. We test this conjecture in the lab. In a pretest, we classify participants by their social value orientation. Individuals who are rivalistic in an allocation task indeed bid more aggressively in a laboratory oligopoly market. This disciplines incumbents. We conclude that the existence of rivalistic attitudes may justify antitrust policies that protect mavericks.

A potentially effective way to influence people's fire prevention behavior is letting them experience a fire in an immersive virtual environment (IVE). We analyze the effects of experiencing a fire in an IVE (versus an information sheet) on psychological determinants of behavior-knowledge, vulnerability, severity, self-efficacy, and locus of control-based mainly on arguments from Protection Motivation Theory and the Health Belief Model. Crucial in our setup is that we also relate these determinants to actual prevention behavior. Results show that IVE has the hypothesized effects on vulnerability, severity, and self-efficacy, and an unexpected negative effect on knowledge. Only knowledge and vulnerability showed subsequent indirect effects on actual prevention behavior. There remains a direct positive effect of IVE on prevention behavior that cannot be explained by any of the determinants. Our results contradict the implicit assumption that an induced change in these psychological determinants by IVE, necessarily implies a change in behavior. A recommendation for research on the effects of IVE's is, whenever possible, to study the actual target behavior as well.

Raub and Weesie (1990) proposed a game theoretical model addressingeffects of network embeddedness on conditional cooperation between two actors.This work showed that network embeddedness can facilitate conditional coopera-tion by reducing uncertainty, in line with a number of follow-up contributions andconsistently with results from other modelling approaches. This research focusedmainly on interactions between two parties embedded in a network. In the presentpaper, I extend a closely related model towardsN-person collective good problems,combining conditional cooperation based on direct monitoring via network ties andobservation of group output in an uncertain environment. The focus is on a maxi-mally simple yet empirically relevant case, a core-periphery network in which onlycore-members can directly observe each other’s contributions to a collective effort,whereas peripheral members only observe a noisy signal indicating aggregated con-tributions. I propose the possibility of a‘rational exploitation of the core by the pe-riphery’. Strategy-profiles in which free-riding of peripheral members is toleratedwhile core-members cooperate conditionally, are not only individually rational butalso payoff-superior to profiles with universal conditional cooperation if uncer-tainty is sufficiently high and the number of peripheral members is sufficiently low.

When examining a social phenomenon, theoretical and empirical sociologists require a model. Although models are by definition simplified representations of theories of reality, sociologists typically argue that the micro-level model of individual behavior should be simplified, but not the model of the macro-level system (including macro-micro and micro-macro links) including the social interactions. Using the example of research on exchange we theoretically and empirically demonstrate the possibly disastrous consequences of overly simplifying the model of the macro-level system. We show that by oversimplification, the mainstream model of exchange (so-called split pool exchange) precludes explaining the macro-level phenomenon. Consequently, we question the ecological validity of exchange research for real-life exchanges. We conclude by listing advantages of a more complex and realistic macro-level model of exchange (that is, pure exchange) for research in the social sciences.

The micro-macro transition is a core problem of sociological theory building. Micro-intentions and micro-behavior do not straightforwardly translate into corresponding phenomena on the macro level, due to potentially existing rival mechanisms and the dynamics and complexity of social interactions. This chapter proposes an integrated statistical approach to studying the micro-macro transition by combining a random coefficient multilevel approach with the Stochastic Actor-Oriented Model. This is elaborated for the substantively interesting and topical question whether the growing ethnic and religious diversity in our societies, along with the well-known tendency for homophily, necessarily lead to a decline in social cohesion. The German part of the CILS4EU data is used to tackle this empirically. We investigate how religious homophily plays out differently depending on the context defined by the composition of the classroom, and explore the potential of simulation methods to explain this macro-level phenomenon from micro-level network dynamics. The empirical puzzle as stated is answered by a model representing homophily in a straightforward way, taking account of the variability between classrooms and the uncertainty about the parameter values; but a closer analysis reveals a further puzzle, which we leave for future research.