A scalar value, represented as lambda, specifying the relative importance of the Regularization function.
Raising the Regularization rate reduces overfitting but may make the model less accurate.
re-ranking
The final stage of a recommendation system, during which scored items may be re-graded according to some other (typically, non-ML) algorithm. Re-ranking evaluates the list of items generated by the scoring phase, taking actions such as
Eliminating items that the user has already purchased.