Changes to the media environment have increased polarized voting in America through both addition and subtraction. We argue that the decline of local newspapers has contributed to the nationalization of American politics: as local newspapers close, Americans should rely more heavily on available national news or partisan heuristics to make political decisions. We assess the impact of newspaper closure on polarized voting, using genetic matching to compare counties that are statistically similar on the observables but for the loss of a local newspaper. We identify a small but significant causal decrease in split-ticket voting in presidential and senatorial elections in these matched communities: in areas where a newspaper closes, split-ticket voting decreases by 1.9 percent.

中文翻译：

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报纸停刊使投票行为两极分化

媒体环境的变化通过加法和减法增加了美国的两极分化投票。我们认为，地方报纸的衰落促成了美国政治的国有化：随着地方报纸的关闭，美国人应该更加依赖现有的国家新闻或党派启发式方法来做出政治决策。我们评估报纸关闭对两极分化投票的影响，使用基因匹配来比较在可观察量上统计相似但当地报纸丢失的县。我们发现，在这些匹配社区的总统和参议员选举中，分票投票减少了一个小但显着的因果关系：在报纸关闭的地区，分票投票减少了 1.9%。