In this design, a researcher should foresee the formation of two groups: one (or more) is the experimental group consisting of participants given an experimental intervention, and the other is the control group composed of participants who are not either given any experimental manipulation or provided with any test stimuli. The researcher should assign the participants in each group randomly. Subjects cannot decide which group they are going to be in. This random assignment of participants to any of the groups is known as randomization, and placement in any group is a matter of chance. Subsequently, the researcher administers the experimental intervention. In other words, s/he provides the experimental group with relevant stimuli by determining the time, setting, and situation on her/his own. Using this design, the researcher establishes a dependent variable that can be measured both before and after the independent variable is introduced. These are termed as pre-test and post-test measurements, and they indicate if the experimental process has any effect or not. This gauges the effect that the independent variable has over the dependent variable, namely the main focus of that experimental research.