An app used to predict your strength in chess960 or crazyhouse based from your strength in chess on bullet, blitz, rapid and classical. I did this last year.
You can select servers such as lichess and chesscom. Can also select the regressor, either statsmodels or xgboost.
app : https://rating-correlations.streamlit.app/
source: GitHub - fsmosca/Rating-Correlations: Predicts chess960 or crazyhouse ratings given bullet or blitz and others for either Lichess.org or Chess.com servers.
I input my bullet and blitz rating from lichess and using xgboost, the app will predict my chess960 rating.
There are distribution and SHAP plots if you enable them.