Response Set
A response set is the human tendency to answer questions in ways that are the most complimentary, or flattering, to the respondent rather than telling the absolute truth.
For instance, a child might find it preferable to outwardly agree with what an adult is saying rather than speaking their mind. This relates to the human desire to not offend or anger others, as well as to present a positive representation of themselves. This tendency, unfortunately, can severely skew the results of psychological research if an excessive amount of emphasis is placed on the results of personal interviews, interactions and direct observations. Some methods of guarding against this are using anonymous self-report instruments and covert observation (such as through a two-way mirror).