Questions

C1. What is Ad stock (describe and show Adstock included in a sales prediction model for two types of media)?

C2. What is Marginal Return on Marketing Investment (Marginal ROMI) and why is it preferable in most situations to using Total Return on Investment (Total ROMI)?

C3. What are advertising cross-channel effects? (discuss with respect to two kind of media channel, you may use drawing a table or formula to assist that explanation)?

C4. Briefly explain why variables should be mean centred before creating interaction terms.

C5. What is a normative model? How does it differ from a predictive model?

C6. What is the term 'VIF value,' (explain how it is used and how to interpret VIF for a variable in a model, provide an example indicating the threshold level(s) you would look for in model evaluation)?