3 basic approaches to personality research: overview: systematic observation: observing behaviour of subjects at precise points in time, at prescribed intervals or under specified conditions or circumstances. The experimental method: requires 2 criteria to be met, a factor that is hypothesized to cause the behaviour being studied is systematically varied, all other possible causative factors are held constant. Independent variable: factor that is varied systematically: depended variable: the behaviour that is to be observed. Evaluation of the experimental method: the experimental method gives us confidence that the relationships observed are cause- and-effect relationships, experiments can be done in psychological laboratories. Results may be artificial because the context is different from real life. The magnitude (strength) of a correlation can tell us how well one variable can predict another: direction of the correlation: two variables can be related directly or inversely. Direct/positive correlation: positive correlation is found between the iqs of parents and children; brighter parents have brighter children.