Correlation analysis is a method used to understand the relationship between two or more variables. It helps to determine if there is a connection, and if so, the strength and direction of that connection. Full definition
I will cover here how one can correlation analysis between equity curves. (alvarezquanttrading.com)
The trouble is that pure correlation analysis does not provide for a sufficient understanding of human behaviour. (sciencedaily.com)
Recent changes in stock correlations — With one exception, all of the above correlation analyses run from no earlier than 1965 to no later than 2015. (mindfullyinvesting.com)