- shows a relationship between 2 variables, both may already be occurring, but in order to find out if they are related the researcher must measure the variable then calculate a correlation. the relationship can be plotted on a scatter graph.
+ replicable - data can be from questionnaires
+ shows relationship - positive occurs when variable increases as the other increases and negative occurs when variable increases as the other decreases
- it is not possible to find out whether one thing causes another, only whether the two variables are related - no cause and effect