What experiment would be best to answer this question: How effective is video advertising at driving sales in offline stores?

What experiment would be best to answer this question: How effective is video advertising at driving sales in offline stores?

Answer

•  Try a geo-targeted method. Only show the ad to specific people in specific regions and compare the results to those who didn't see the ad.
•  Run a questionnaire using a random sample to see if they think the ads were really the factor that enticed them to visit their website. Compare this with time-on-site analytics for further insight.
•  Just apply the user-based method that is part of Google's cross-device tracking tools and a data management platform to see what channels are really working and not working.
•  Try a randomized brand-lift experiment to see whether website visits increased in areas where the mobile video campaign was running. Verify with analytics' data.
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