If participants know if they are in a control or treatment group, they can adapt their behaviour to influence the outcome that researchers are trying to measure. If the treaters are aware of the group`s assignment, they may treat the participants differently and thus directly or indirectly influence the final results. To use a Likert scale in a survey, present participants with Likert-type questions or statements and a continuum of items, usually with 5 or 7 possible answers, to capture their degree of agreement. A quasi-experience is a kind of research design that tries to establish a cause-and-effect relationship. The main difference with real experience is that groups are not randomly assigned. Researcher Robert Rosenthal has spent much of his career showing that this kind of involuntary variation in the procedure actually affects participants` behaviour. In addition, the experientator`s expectations of how participants in the experiment “should” are an important source of this variation. This result is called the experimental waiting effect (Rosenthal, 1976). For example, when an experimenter expects participants in a treatment group to do better than participants in a control group at a task, they may unintentionally give clearer instructions or more encouragement to treatment group participants or give them more time to complete the task. In one striking example, Rosenthal and Kermit Fode had several students train rats in a lab psychology class to walk through a maze. Although the rats were genetically similar, some students said they worked with “mazehellen” rats raised as good learners, and other students said they worked with “maze-dull” rats that had been bred to be poor learners.
Certainly, during five days of training, the “mazehellen” rats reacted more correctly, reacted more quickly and improved more consistently than the “maze-dull” rats (Rosenthal-Fode, 1963). Clearly, it was the students` expectations of how the rats would cope that made the difference. But how? Some evidence comes from data collected at the end of the study, which showed that students who expected their rats to learn quickly quickly felt more positive about their animals and indicated that they were friendlier to them (for example. B more behavior with them). Accidental error is reduced with a more precise instrument (measurements become thinner) and with more repeatability or reproducibility (precision). Consider a common laboratory experiment in which you must determine the acid content in a vinegar sample by observing the volume of sodium hydroxide solution needed to neutralize a certain volume of vinegar. You experience it and you get value. Just to be on the safe side, repeat the process on another identical sample of the same bottle of vinegar.