The Media Bias Effect (MBE) represents the biasing influence of the nonverbal behavior of a TV interviewer on viewers’ impressions of the interviewee. In the MBE experiment, participants view a 4-min made-up political interview in which they are exposed only to the nonverbal behavior of the actors. The interviewer is friendly toward the politician in one experimental condition and hostile in the other. The interviewee was a confederate filmed in the same studio, and his clips are identical in the two conditions. This experiment was used successfully in a series of studies in several countries (Babad and Peer in J Nonverbal Behav 34(1):57–78, 2010. https://doi.org/10.1007/s10919-009-0078-x) and was administered in the present research. The present investigation focused on the interviewer's source credibility and its persuasive influence. The viewers filled out questionnaires about their impressions of both the interviewer and the interviewee. A component of "interviewer's authority" was derived in PCA, with substantial variance in viewers' impressions of the interviewer. In our design, we preferred the conception of Epistemic Authority (Kruglanski et al. in Adv Exp Soc Psychol 37:345–392, 2005)—based on viewers' subjective perceptions for deriving authority status—to the conventional design of source credibility studies, where dimensions of authority are pre-determined as independent variables. The results demonstrated that viewers who perceived the interviewer as an effective leader demonstrated a clear MBE and were susceptible to his influencing bias, but no bias effect was found for viewers who did not perceive the interviewer as an effective leader. Thus, Epistemic Authority (source credibility) moderated the Media Bias Effect.

媒体偏见效应（MBE）代表电视采访者的非语言行为对观众对受访者印象的偏见影响。在 MBE 实验中，参与者观看 4 分钟的虚构政治采访，在采访中他们只接触到演员的非语言行为。采访者在一种实验条件下对政客友好，而在另一种实验条件下则敌对。受访者是在同一摄影棚拍摄的同伙，他的片段在两种情况下是相同的。该实验已成功用于多个国家的一系列研究（Babad 和 Peer in J Nonverbal Behav 34(1):57–78, 2010. https://doi.org/10.1007/s10919-009-0078-x）并在本研究中进行了管理。本次调查的重点是采访者消息来源的可信度及其说服力。观众填写了调查问卷，了解他们对采访者和受访者的印象。 “采访者权威”的一个组成部分是在 PCA 中得出的，观众对采访者的印象存在很大差异。在我们的设计中，我们更喜欢认知权威的概念（Kruglanski et al. in Adv Exp Soc Psychol 37:345–392, 2005）——基于观众对得出权威地位的主观看法——而不是源可信度研究的传统设计，其中权威的维度是预先确定为自变量的。结果表明，认为采访者是有效领导者的观众表现出明显的MBE，并且容易受到他的影响偏见的影响，但对于不认为采访者是有效领导者的观众，没有发现偏见效应。因此，认知权威（来源可信度）调节了媒体偏见效应。