# Correlation

## Asset correlation

The correlation page is only used if you select the `asset correlation`

option on the `model`

page. The correlation page allows you to set
explicit cross-correlation across the assets in your portfolio.

### Correlation values

Correlation between any pair of assets must be between `-1`

and `1`

.
Correlation of `0`

means the assets are independent.

### Valid correlation matrix

In order to work with our model, the correlation matrix must be
positive-definite. Generally speaking if your data is based on real-world
correlation, it will likely be positive-definite.

If your correlation matrix is not positive-definite, you will see an
error at the top of the page.

If the matrix is not valid, we can usually adjust the matrix to generate
a valid positive-definite matrix. Click the button to update the matrix to
the adjusted matrix.

If you don’t like the revised matrix, press Control-Z (or Command-Z) to undo
the changes and make any necessary adjustments yourself.