R xgboost package parameters relation

Question

After reading the docs, it's not 100% clear to me the difference and the relation between the parameters eval_metric , maximize e feval .

For example, while doing linear regression, i'm setting eval_metric to a custom kappa function, then maximize = TRUE. What's the difference between eval_metric and feval ?

Thanks!

Answer 1

So, to answer my own question: feval and eval_metric are the same thing. The same applies to obj and objective . It's all on github repo: https://github.com/dmlc/xgboost .