A control group is a group in an experiment that does not receive the treatment or intervention being tested. It serves as a baseline to compare the effects of the treatment on other groups.
Experimental Group: The group in an experiment that receives the treatment or intervention being tested.
Random Assignment: A process used to assign participants to different groups using randomization, ensuring each participant has an equal chance of being placed in any group.
Placebo Effect: $\text{A phenomenon where participants experience changes due to their expectations about }$ receiving treatment rather than the treatment itself.