LONDON: A tie up between Facebook, the social media giant, and Dunnhumby, the customer science company, promises to deliver greater understanding of the effectiveness of brands' spending in social.

The partnership links Dunnhumby data on 17m UK shoppers with Facebook's 37m monthly users and enables brands to assess the impact of different ad creative and frequency via a straightforward methodology that sees one group of Facebook users exposed to an ad while a control group is not.

On the assumption that all other factors are equal – something observers were quick to point out is not usually the case – then advertisers ought to be able to measure the impact of a Facebook campaign on sales.

It will, said Alex North, head of partnerships at Facebook in EMEA, "help advertisers understand the true business of advertising on Facebook in a granular, anonymised and secure way.

"One of the key benefits is that the solution will help advertisers understand their Facebook campaign metrics – what is working and what is working less well – and optimise those campaigns based on an objective understanding of whether their campaigns are driving sales."

In trials with FMCG brands, Dunnhumby reported that one advertiser tested six different creative executions with the winning version producing a 10% sales uplift. Another explored frequency, serving one ad per week to one group, two ads per week to another, and found that exposing users to more ads resulted in a 6%-7% uplift in sales.

Agencies and marketers generally welcomed the opportunity to quantify the results of advertising on Facebook, while sounding a note of caution about relying too heavily on the figures.

"This of course won't provide an immediate correlation between social habits and sales as we know shopping habits and the data landscape is a lot more complex than that," said Bonnie Boodram, head of e-commerce at Leo Burnett/Arc London.

"However I am optimistic this new insight taken in combination with traditional advertising data will provide new insight on customer behaviour on and offline," she told The Drum.

Tina Moffett, senior marketing analyst at Forrester Research, concurred: "The longer term strategy marketers must take is to measure all tactics across all channels," she said.

Data sourced from Marketing Week, The Drum, Marketing; additional content by Warc staff