correlation

1. (statistics) One of the several measures of the linear statistical relationship between two random variables, indicating both the strength and direction of the relationship.Examples: "For example, scientists can use data from larger studies about the correlation between antibody levels and vaccine efficacy in adults to make a prediction about vaccine efficacy in children."; "While there are physiological changes throughout the day that may influence how you handle things, there are bigger correlations between mental health and well-being and time of year, according to Rutledge."countableuncountable

2. (algebra) An isomorphism from a projective space to the dual of a projective space, often to the dual of itself.countableuncountable