A marketing team wants to test whether a new Instagram ad fe…

A marketing team wants to test whether a new Instagram ad featuring a celebrity spokesperson increases click-through rates. They randomly assign 1,000 users to see the ad with the celebrity and another 1,000 users to see the same ad without the celebrity. What is the primary purpose of showing the ad without the celebrity?

A soft drink company runs an ad campaign on both TikTok and…

A soft drink company runs an ad campaign on both TikTok and YouTube to compare which platform generates more positive brand sentiment. However, the TikTok ad features a popular Gen Z influencer, while the YouTube ad features a general brand message without any influencer. Why is it hard to draw valid conclusions from this experiment?