Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Pairwise correlations between features. The strength of the correlation (Pearson’s r) between two features is shown by the colour of the cell at the intersection of x- and y-axis variables: darker colours indicate stronger correlations. Text annotations are provided only where r > 0.5.
