If "train", "valid", and "xval" parameters are FALSE (default), then the training residual deviance value is returned. If more than one parameter is set to TRUE, then a named vector of residual deviances are returned, where the names are "train", "valid" or "xval".
h2o.residual_deviance(object, train = FALSE, valid = FALSE, xval = FALSE)
An H2OModel or H2OModelMetrics
Retrieve the training residual deviance
Retrieve the validation residual deviance
Retrieve the cross-validation residual deviance