Calvão Angelo Mondaini, Crokidakis Nuno, Anteneodo Celia
Department of Physics, PUC-Rio, Rio de Janeiro, RJ, Brazil.
Institute of Physics, Universidade Federal Fluminense, Niterói, RJ, Brazil.
PLoS One. 2015 Sep 29;10(9):e0137732. doi: 10.1371/journal.pone.0137732. eCollection 2015.
Elections, specially in countries such as Brazil, with an electorate of the order of 100 million people, yield large-scale data-sets embodying valuable information on the dynamics through which individuals influence each other and make choices. In this work we perform an extensive analysis of data sets available for Brazilian proportional elections of legislators and city councilors throughout the period 1970-2014, which embraces two distinct political regimes: a military regime followed by a democratic one. We perform a comparative analysis of elections for legislative positions, in different states and years, through the distribution p(v) of the number of candidates receiving v votes. We show the impact of the different political regimes on the vote distributions. Although p(v) has a common shape, with a scaling behavior, quantitative details change over time and from one electorate to another. In order to interpret the observed features, we propose a multi-species model consisting in a system of nonlinear differential equations, with values of the parameters that reflect the heterogeneity of candidates. In its simplest setting, the model can not explain the cutoff, formed by the most voted candidates, whose success is determined mainly by their peculiar, intrinsic characteristics, such as previous publicity. However, the modeling allows to interpret the scaling of p(v), yielding a predictor of the degree of feedback in the interactions of the electorate. Knowledge of the feedback is relevant beyond the context of elections, since a similar interactivity may occur for other social contagion processes in the same population.
选举，特别是在像巴西这样拥有约1亿选民的国家，会产生大规模数据集，其中包含有关个体相互影响和做出选择的动态过程的宝贵信息。在这项工作中，我们对1970年至2014年期间巴西立法者和市议员比例选举可用的数据集进行了广泛分析，这涵盖了两种不同的政治体制：军事体制之后是民主体制。我们通过获得v票的候选人数量的分布p(v)，对不同州和年份的立法职位选举进行了比较分析。我们展示了不同政治体制对选票分布的影响。尽管p(v)具有共同的形状，呈现出标度行为，但定量细节会随时间以及从一个选区到另一个选区而变化。为了解释观察到的特征，我们提出了一个多物种模型，该模型由一个非线性微分方程组组成，其参数值反映了候选人的异质性。在其最简单的设定中，该模型无法解释由得票最多的候选人形成的截止情况，这些候选人的成功主要由其特殊的内在特征决定，比如先前的宣传。然而，该建模能够解释p(v)的标度，得出选民互动中反馈程度的预测指标。反馈的知识在选举背景之外也很重要，因为在同一人群中的其他社会传播过程可能会出现类似的互动性。
