Large-scale experiments involve conducting research on a large population or group of individuals to study the effects of certain variables or interventions. These experiments typically involve a significant number of participants or subjects and are often carried out in real-world settings to provide more generalizable results. Large-scale experiments can help researchers understand complex phenomena, test hypotheses, and draw conclusions about cause-and-effect relationships. They are commonly used in fields such as psychology, sociology, education, and public health to generate robust and reliable evidence.