Facebook will offer more advertisers the ability to measure campaign brand lift, but brands will need to trust Facebook to grade its own homework.

Facebook is raising its bid for brand advertisers’ TV budgets.

Facebook will offer advertisers the option of having the company measure how the ads it sells influence people’s awareness of a brand and how that compares with advertisers’ TV campaigns, the company announced on Friday.

With the new measurement program called Facebook Cross-Platform Brand Lift, Facebook will survey people shown ads across Facebook, Instagram and its Audience Network ad network to see if they remember an ad and the corresponding brand. Then it will report how “brand lift” on Facebook compares with brands’ TV ad campaigns measured in a similar way by TV ad analytics firm iSpot.

Facebook expects to roll out the cross-platform brand lift measurement program to advertisers sometime in early 2018. However today Facebook is rolling out a similar Facebook-and-TV brand-lift measurement program run by Nielsen called Nielsen Total Brand Effect With Lift. That program is now available to advertisers in the US and the UK through Facebook’s sales team and will open up to advertisers in Australia by the end of the year.

Being able to measure impact of Facebook ads on brand lift and compare it against TV and other non-Facebook campaigns is not new. Facebook already offers brand lift studies through its sales team, and advertisers can order similar studies for Facebook and non-Facebook campaigns from companies like Millward Brown and Nielsen.

But the way that advertisers will now be able to measure and compare brand lift for their Facebook and TV campaigns is new in an important way for both Facebook Cross-Platform Brand Lift and Nielsen’s Total Brand Effect With Lift. Before iSpot or Nielsen poll people on what ads they did or didn’t see and how those ads did or didn’t impact them, they will ask whether a person watched a specific TV show. If a person answered “yes,” then they would have had an opportunity to see the corresponding brand’s TV ad, and the TV ad’s brand lift can be measured with follow-up questions like “Do you remember seeing an ad from Brand X?” and “Do you plan to buy Brand X’s product shown in that ad?” If a person answered “no” that they did not watch the show, then they would not be included in the TV ad’s brand lift results. By adopting this opportunity-to-see question, iSpot and Nielsen are better able to qualify whether a person would or would not have seen a brand’s TV ad and solidify the TV side of an advertiser’s brand-lift results.

There is another important difference when it comes to the Facebook’s upcoming brand-lift measurement program. That program will be available to advertisers with lower spend minimums than those who qualify for third-party measurement. It will also offer brands a self-serve platform to configure their TV-and-Facebook brand-lift studies and view the results.

The roll-out of Facebook Cross-Platform Brand Lift is a shrewd move by Facebook. If Facebook’s brand lift studies can show more advertisers that their ad spend on the platform yields compelling brand metrics, it could lure bigger budgets across a wider set of advertisers. The cross-platform studies also provide a common language across media buying teams. By showing Facebook brand lift next to that of TV campaigns, Facebook could stand to gain budget allocations if marketers see that pairing Facebook and TV together provides better results by running cross-platform campaigns.

While having Facebook measure brand lift may lower the requirements for advertisers interested in tracking brand impact, it does require a higher leap of faith, since Facebook will be effectively grading its own homework by surveying its users about the ads it sold, and given the series of 10 measurement errors that Facebook has disclosed over the past year, including one announced earlier this year in which Facebook incorrectly charged advertisers for video ad carousel campaigns.