A type of bias in media and market research that occurs when an interviewer consciously or nonconsciously influences responses from participants during an interview, resulting in inaccurate responses. Interviewers can bias responses through either their behavior (the way they probe, their body language, tone of voice, verbal or non-verbal cues) which could affect participants’ responses, or through their observations of participants (based on accent, tone of voice, use of language, ethnicity, clothing) which could cause distortions in the magnitude or direction of a participant’s responses.