In recent years, several instances of political actors who created fake grassroots activity on the Internet have been uncovered. We propose to call such fake online grassroots activity digital astroturfing, and we define it as a form of manufactured, deceptive and strategic top-down activity on the Internet initiated by political actors that mimics bottom-up activity by autonomous individuals. The goal of this paper is to lay out a conceptual map of the phenomenon of digital astroturfing in politics. To that end, we introduce, first, a typology of digital astroturfing according to three dimensions (target, actor type, goals), and, second, the concept of digital astroturfing repertoires, the possible combinations of tools, venues and actions used in digital astroturfing efforts. Furthermore, we explore possible restrictive and incentivizing countermeasures against digital astroturfing. Finally, we discuss prospects for future research: Even though empirical research on digital astroturfing is difficult, it is neither impossible nor futile.

Almost since the advent of the Internet, there has been great interest in analyzing and understanding online communication from the perspective of public sphere theory. The question of whether the properties of the Internet and, specifically, social media actually contribute to the public sphere is the matter of ongoing and somewhat heated scientific debate. The aim of the article is twofold. First, we propose a hierarchical model of generalized functions of public sphere. On a theoretical level, we interweave different strands of thought on the public sphere, and the resulting model is more inclusive and less rigid than each of those strands on their own. We identify four generalized functions: identity building, agenda-setting, control and criticism, and deliberation. The Internet does not contribute equally to these functions and we evaluate the impact of the Internet on each of these functions as a diminishing marginal utility. Second, we empirically explore the plausibility of our model in a global comparative analysis with focus on the Internet. With the help of macro-level variables which indicate the structural preconditions for a public sphere, we identify the highest possible function of the public sphere for each country to which the Internet can potentially contribute. Based on this approach, future research can be contextualized: case-studybased research can plausibly articulate expectations regarding the impact of the Internet on the public sphere.

In recent years, several instances of political actors who created fake grassroots activity on the Internet have been uncovered. We propose to call such fake online grassroots activity digital astroturfing, and we define it as a form of manufactured, deceptive and strategic top-down activity on the Internet initiated by political actors that mimics bottom-up activity by autonomous individuals. The goal of this paper is to lay out a conceptual map of the phenomenon of digital astroturfing in politics. To that end, we introduce, first, a typology of digital astroturfing according to three dimensions (target, actor type, goals), and, second, the concept of digital astroturfing repertoires, the possible combinations of tools, venues and actions used in digital astroturfing efforts. Furthermore, we explore possible restrictive and incentivizing countermeasures against digital astroturfing. Finally, we discuss prospects for future research: Even though empirical research on digital astroturfing is difficult, it is neither impossible nor futile.

Conspiracy theories as alternative explanations for events and states of affairs enjoy widespread popularity. We test one possible explanation for why people are prone to conspiratorial thinking: We hypothesize that conspiratorial thinking as an explanation for events increases as the probability of those events decreases. In order to test this hypothesis, we have conducted five experiments in which participants were exposed to different information about probabilities of fictional events. The results of all experiments support the hypothesis: The lower the probability of an event, the stronger participants embrace conspiratorial explanations. Conspiratorial thinking, we conclude, potentially represents a cognitive heuristic: A coping mechanism for uncertainty.

In this study, we analyze whether the mere volume of presence in mass media and the mere volume of activity on social media convey advantages to candidates in parliamentary elections. Based on the theoretical model of bounded rationality, we call these potential effects brute force effects. During the last month of the election campaign of the Swiss federal election of 2015, we have tracked the presence of all 873 candidates in the canton of Zurich, the most populous canton, in a broad sample of mass media. Additionally, we have tracked those candidates' activity on Facebook and Twitter. The results of our multilevel Bayesian estimates show that mass media presence has a consistent non-trivial impact on different aspects of electoral outcome. Furthermore, social media activity also has a non-trivial impact, but only in terms of resonance (reactions to candidates' social media activity). Overall, our results suggest that brute force effects of of mass media presence and social media activity can have substantial impact on voting behavior.