Experiment Definition | Psychology

An experiment is a scientific procedure with the purpose of testing a hypothesis, making a discovery, or testing if something is true or not. There are two types of experiments, a quasi-experiment and a true experiment. When a researcher randomly assigns participants into groups with a control and an experimental subset and then manipulates the control, this is called a true experiment. A quasi-experiment is without a random assignment of participants into groups. True experiments are generally strongly preferred as they help establish a true cause-and-effect conclusion.

For example, my cat sometimes thinks I am an experiment, but it cannot establish a true cause-and-effect between his feeding times and his incessant crying in the morning, especially since I purchased earplugs.