Effects of Message-Sidedness on Perceived Source Bias: When Presenting Two Sides Does Versus Does Not Alleviate Concerns About Bias.

Communicators commonly present two-sided messages to avoid being perceived as biased. This approach equates bias with one-sidedness rather than divergence from the position supported by available data. Messages often concern topics with mixed qualities: a product is exceptional but expensive; a politician is inexperienced but ethical. For these topics, providing a two-sided message should reduce perceived bias according to both views of bias as one-sidedness and divergence from available data. However, if perceived bias follows divergence from available data, for topics viewed as one-sided (univalent), a two-sided message should not reduce perceived bias. Across five studies, acknowledging two sides reduced perceived bias for novel topics. In two of the studies, two-sidedness no longer reduced perceived bias for topics viewed as univalent. This work clarifies that people conceptualize bias as a divergence from available data, not simply one-sidedness. It also clarifies when and how to leverage message-sidedness to reduce perceived bias.