Hybrid recommendation systems combine multiple recommendation systems to improve recommendations. Which of the following methods may be implemented by Hybrid systems?

$(1)$ Weighting recommendations to calculate a final recommendation.

$(2)$ Switching between different recommendation models for a final recommendation.

$(3)$ Mixed recommendations i$.$e$.$ present items from different recommendation systems together.

Answer choices

Select an option

$(1)$ & $(2)$

$(1)$ & $(3)$

Only $(1)$

All the methods may be implemented