Facebook is trying to answer the one question on every retailer’s mind: Does advertising on the 1.3bn-strong social network actually help increase sales?

In a world that celebrates “likes” and “follows”, the social network has begun to focus instead on ringing tills. It is trialling a ‘buy’ button and detailing how online ads affect in-store sales – something the advertising industry has never previously been able to do. Winning over retailers will help Facebook with its next major challenge: increasing the amount each advertiser spends on the network. But, dogged by privacy scandals for years, it has to tread carefully as it partners with data brokers and makes use of retailers’ own customer information databases.

Eric Roza, chief executive of Colorado-based Datalogix – one of the data brokers partnering with Facebook – said the ability to calculate straightforward metrics such as return on investment is becoming more important as concerns grow about online ad fraud. “A bot can’t buy a product in a store,” he said.

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