When expertise backfires: contrast and assimilation effects in persuasion

Br J Soc Psychol. 2002 Dec;41(Pt 4):495-519. doi: 10.1348/014466602321149858.


It was proposed that source cues bias message processing in a direction opposite to cue valence if message content violates cue-based expectancies (contrast hypothesis), but consistent with cue valence if message content is ambiguous (bias hypothesis). In line with these hypotheses, students (N = 123) reported less favourable thoughts and attitudes after reading weak arguments presented by a high (vs. low) expertise source (Expts 1 and 2), and reported more favourable thoughts after reading strong arguments presented by a low (vs. high) expertise source (Expt 2). Conversely, students' thoughts and attitudes were more (less) favourable when a high (low) expertise source presented ambiguous arguments (Expt 2). Results are discussed in relation to dual- vs. single-process accounts of persuasion and models of assimilation and contrast in social judgment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Analysis of Variance
  • Attitude
  • Awareness
  • Cognition
  • Cues*
  • Germany
  • Humans
  • Male
  • Persuasive Communication*
  • Professional Competence*
  • Students / psychology*