Demand characteristics refer to a type of response bias where participants alter their response or behavior simply because they are part of an experiment. This arises because participants are actively engaged in the experiment, and may try to figure out the purpose, or adopt certain behaviors they believe belong in an experimental setting. Martin Orne was one of the first to identify this type of bias, and has developed several theories to address their cause. His research points to the idea that participants enter a certain type of social interaction when engaging in an experiment, and this special social interaction drives participants to consciously and unconsciously alter their behaviors There are several ways that this bias can influence participants and their responses in an experimental setting. One of the most common relates to the motivations of the participant. Many people choose to volunteer to be in studies because they believe that experiments are important. This drives participants to be "good subjects" and fulfill their role in the experiment properly, because they believe that their proper participation is vital to the success of the study. Thus, in an attempt to productively participate, the subject may try to gain knowledge of the hypothesis being tested in the experiment and alter their behavior in an attempt to support that hypothesis. Orne conceptualized this change by saying that the experiment may appear to a participant as a problem, and it is his or her job to find the solution to that problem, which would be behaving in a way that would lend support to the experimenter's hypothesis. Alternatively, a participant may try to discover the hypothesis simply to provide faulty information and wreck the hypothesis. Both of these results are harmful because they prevent the experimenters from gathering accurate data and making sound conclusions. Outside of participant motivation, there are other factors that influence the appearance of demand characteristics in a study. Many of these factors relate to the unique nature of the experimental setting itself. For example, participants in studies are more likely to put up with uncomfortable or tedious tasks simply because they are in an experiment. Additionally, the mannerisms of the experimenter, such as the way they greet the participant, or the way they interact with the participant during the course of the experiment may inadvertently bias how the participant responds during the course of the experiment. Also, prior experiences of