'weights' argument in cv.grpsurv() does not work

[irisk2050]

I am trying to test different weights on my cox LASSO model to see if it will improve the model's performance.

However, there was no difference in the C-index scores when the model was weighted vs any of the weights I tested (1, 2.5, 5, 7.5, 10). The 'weights' argument is not being applied to the model.

[pbreheny]

I'm confused as to what you want -- there is no weights argument in grpsurv().

[irisk2050]

I saw a stackoverflow post that used 'weights' inside cv.grpsurv().

I've been using it in my model below:

`
weights = ifelse(train_surv_ls == 1, 10, 1)

cox_ls = cv.grpsurv(
X = x_train,
y = train_surv_ls,
group = group,
lambda = lambda_values,
penalty = 'grLasso',
nfold = 10,
weights = weights
)
`

The code is running successfully in Databricks. However, it makes sense that if there is no weights argument why the model is not accounting for the weights.