Final answer:
Random assignment is the process used in experimental design to ensure all participants have an equal chance of being placed in either the experimental or control group, which helps preserve the integrity of the study.
Step-by-step explanation:
Random Assignment in Experimental Design
The process that ensures participants have an equal likelihood of being assigned to experimental or control conditions is known as random assignment. This fundamental aspect of experimental design is crucial for maintaining the validity of the results by minimizing the effects of lurking variables. During random assignment, participants are assigned to either the experimental group or the control group in a random manner, often facilitated by statistical software. This method ensures that any observed differences between groups are likely due to the manipulation of the independent variable rather than preexisting differences among participants. Furthermore, random assignment aids in preventing research bias and maintaining the integrity of the study.
It is key to remember that the control group receives a placebo or no treatment, highlighting the effects of the experimental manipulation. An ideal experiment also includes measures to prevent experimenter bias, such as blinding those who score the tests to group assignments. Properly designed experiments allow for the assumption that differences in outcomes are attributable to the independent variable's influence.