I would use Geo-Based method to determine whether an ad drove incremental results.
- Store-Based
- User-Based
- Product-based
- Geo-Based
The correct answer is: Geo-Based
Explanation: Google utilizes experiments to assess incrementality by dividing users into treatment and control groups, avoiding retroactive comparisons. The Geo-based experiments then evaluate the effectiveness of ads in driving essential business outcomes, such as online buys or in-store sales.