Changes in political perceptions and preferences may result from the combined effects of news from various media. Estimating these combined effects requires the best possible, albeit different, measures of news obtained from self-selected mass media and social media that can be linked to panel survey data concerning perceptions and preferences. For the 2017 Dutch national elections, such data is available. Political perceptions and preferences are affected by news statements in self-selected mass media on issue positions, support and criticism, real world conditions and success and failure, in accordance with the theories on agenda setting and issue ownership, social identity, retrospective voting and bandwagon effects, respectively. Combined effects emerge because many people use both mass media and social media. The latter do more than just reinforce predispositions. Social media also have a mere exposure effect, and a multistep flow effect that amplifies news about party successes and failures from self-selected mass media.

中文翻译：

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大众媒体和社交媒体对政治认知和偏好的综合影响

政治观念和偏好的变化可能是各种媒体新闻的综合影响造成的。估计这些综合影响需要对从自我选择的大众媒体和社交媒体中获得的新闻进行尽可能最好的衡量，尽管这些衡量标准可以与关于感知和偏好的面板调查数据相关联。对于 2017 年荷兰全国选举，此类数据是可用的。根据议程设置和问题所有权、社会认同、追溯性投票和潮流的理论，政治观念和偏好受到自选大众媒体关于问题立场、支持和批评、现实世界条件以及成功和失败的新闻声明的影响效果，分别。综合效应的出现是因为许多人同时使用大众媒体和社交媒体。后者不仅仅是强化倾向。社交媒体也有单纯的曝光效应和多步流动效应，可以放大来自自我选择的大众媒体关于政党成功和失败的消息。