Reliability: Refers to the consistency or stability of measurement over time. In order for personality tests to effectively predict future behavior, they need to be reliable, meaning that they consistently measure the same aspects of an individual's personality.
Predictive Validity: This term refers to the ability of a test to accurately forecast or estimate future behavior. Personality tests with high predictive validity can successfully anticipate how individuals will behave in various situations.
Trait Theory: Trait theory is an approach in psychology that focuses on identifying and measuring stable patterns of behavior, thoughts, and emotions known as traits. It suggests that if we know someone's traits through a reliable and valid assessment tool such as a personality test, we can make predictions about their future behavior.