Truth tracking performance of social networks: how connectivity and clustering can make groups less competent

Our beliefs and opinions are shaped by others, making our social networks crucial in determining what we believe to be true. Sometimes this is for the good because our peers help us form a more accurate opinion. Sometimes it is for the worse because we are led astray. In this context, we address via agent-based computer simulations the extent to which patterns of connectivity within our social networks affect the likelihood that initially undecided agents in a network converge on a true opinion following group deliberation. The model incorporates a fine-grained and realistic representation of belief (opinion) and trust, and it allows agents to consult outside information sources. We study a wide range of network structures and provide a detailed statistical analysis concerning the exact contribution of various network metrics to collective competence. Our results highlight and explain the collective risks involved in an overly networked or partitioned society. Specifically, we find that 96% of the variation in collective competence across networks can be attributed to differences in amount of connectivity (average degree) and clustering, which are negatively correlated with collective competence. A study of bandwagon or “group think” effects indicates that both connectivity and clustering increase the probability that the network, wholly or partly, locks into a false opinion. Our work is interestingly related to Gerhard Schurz’s work on meta-induction and can be seen as broadly addressing a practical limitation of his approach

A judicialização da competição política: o TSE e as coligações eleitorais

Há uma extensa literatura que se debruça sobre os efeitos do poder judiciário no funcionamento dos sistemas políticos. Estaríamos assistindo à judicialização da política? O argumento apresentado é que o entendimento acerca da influência do direito na dinâmica dos sistemas políticos supõe uma noção mais ampla sobre o lócus e o momento em que ocorre sua interferência no funcionamento das democracias contemporâneas. A proposta é discutir a judicialização no que diz respeito à definição das regras da competição político-eleitoral. Para isso, analisaremos a decisão do TSE (Tribunal Superior Eleitoral) referente à verticalização das coligações. O argumento é que o TSE não apenas interpretou uma legislação, mas também estabeleceu um novo regulamento no lugar do poder legislativo. Nossa análise demonstra que a regulamentação das coligações eleitorais é fruto de interação estratégica entre o TSE e o poder legislativo.<br>There is an extensive literature to study the effects of the judiciary power on how political systems work. Is there a judicialization of politics? Our point is that the answer to that question is connected to theoretical questions about the ways to prove and where scholars should look in order to detect the effect of judiciary in democratic systems. In this work we analyze the judicialization of politics under the perspective of the definition of the rules of electoral competition. In order to prove our argument, this article studies how TSE (brazilian judiciary court) rules coalitions in Brazil's political system, known as "verticalização" _the uniformity of party coalitions at state and federal levels. Our case study shows that TSE, in fact, not only interprets the law but, actually, establishes rules, taking the place of the legislative body _which, in turn, made another move. The analysis suggests that the question of judiciary of politics should be seen as an strategic interaction between the two powers