demand characteristics

n. Demand characteristics are aspects of a research study that cue participants to the objectives or desires of the researcher. These effects can be either conscious or unconscious; participants may not realize that demand characteristics have affected their behavior. Demand characteristics may include aspects of the stimulus materials or other elements of the environment, or subtle cues given off by the researcher, including verbal and nonverbal behavior. Research has shown that demand characteristics can have powerful effects on research participants, and that researchers are not very skilled at reducing demand characteristics that are present in their behavior. One common remedy to the problem of demand characteristics in terms of experimenter behavior is the double-blind study, in which both participants and experimenter are unaware of the researchers' objectives and/or the particular experimental condition.

- MWP