What is parsimony?
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In research, this refers to the simplest explanation about the greatest number of observations is favored and logical to the more complex explanations that may be present. It serves to help scientists to develop more of theoretical models in research than published models. It is often associated with the rule of Ockham's razor meaning the simplest explanation is usually the correct one.
Example / Application
Example: Ashe Line Experiment
Application: In the video we see the classic Ashe line experiment where lines of different sizes are demonstrated to a group of individuals who all have to choose which line matches with the one shown by the researcher. It is about conformity, as we see if the participant will choose the correct line matching the one by the researcher or conform to the group who all choose the wrong line, conformity caused the result considering that conformity was the only manipulation in the study. The rule of "parsimony" implies that the simplest explanation is preferred.