Future of TV Briefing: WTF is co-viewing measurement?

Co-viewing measurement is a necessary evil in the TV and streaming ad market.

Ad buyers and sellers want to know how many people may have seen an ad. Which is understandable, but there’s no perfect way for counting how many people were actually in the room when an ad aired. Instead co-viewing measurement relies on probabilistic modeling, a solution that is simultaneously problematic.

What is co-viewing measurement?

Co-viewing measurement is exactly what it sounds like: measuring how many people are in the room together when an ad or program airs on screen. 

How is co-viewing measured?

There are two main methods of measuring co-viewing, but both effectively take a direct co-viewing measurement from a smaller sample of viewers and then project that across the broader TV and streaming audience base.

One method for taking the direct measurement is to have a sample of viewers physically log their TV watching. Nielsen deploys this through what are called personal people meters, in which the sample viewers press a button to tell Nielsen when they are in the room and are about to start watching something, how many people are in the room with them as well as when any of them leave the room. 

The other direct measurement method is to have devices, such as a camera, in the same room as a TV that detect when the TV is on and scan the room for the number of people in it. This is the methodology used by TVision, which provides that data to one of Nielsen’s chief rivals VideoAmp. Little surprise then that TVision commissioned marketing firm Matter More Media to produce a study on co-viewing measurement that calls into question Nielsen’s co-viewing measurement methodology without calling out Nielsen by name.

What’s the problem with Nielsen’s co-viewing measurement methodology?

Humans. It largely relies on people actively logging their TV watching, including how many people they are watching with. Nielsen does have guardrails in place, like monitoring audio to determine if anyone may have left the room and then flagging those in the room to log any changes in who’s watching. But again, ultimately it’s up to people to remember to log the measurements, which is the criticism TVision and Matter More Media lob at this methodology in their study.

“Pushing buttons requires compliance, where TVision is a passive system that is automatically measuring who’s in the room,” said Kelly Abcarian, the former Nielsen executive and current Matter More Media chief strategy officer who wrote the TVision study.

The study cites a simulation conducted by TVision and the Coalition for Innovative Media Measurement that found that a match between active co-viewing measurements and passive co-viewing measurements 56%, which means that 44% of the time one of the methodologies is under- or over-counting compared to the other.

So TVision’s co-viewing measurement methodology is better?

Not necessarily. The camera-based co-viewing measurement system is passive, so it’s not reliant on people actively logging their TV watching. It also measures on a second-by-second basis, so it’s less prone to viewership gaps. But it still requires the camera to be able to accurately analyze the number of people in the room. Also TVision bases its measurement on a sample of 6,000 households, which is less than a third the number of households with Nielsen’s personal people meter.

Moreover, while the industry’s measurement arbiter Media Rating Council has audited Nielsen’s co-viewing measurement methodology, “I haven’t audited TVision. I don’t know how accurate it is, how good it is at measuring people’s faces, whether there’s bias [among the people who] even agree to have these things in their homes,” said Ron Pinelli, svp of digital research and standards at MRC.

OK, so both methodologies have their problems. Isn’t there a better way?

Sure. Either company — both — could install cameras in every room with a TV in every household in the U.S. and also equip every person with a personal people meter to log their TV watching. It’ll be like taking inventory every time you want to chill on the couch. How’s that?

A nightmare. But is this a U.S.-only issue? Like, don’t they measure TV and streaming co-viewing in the U.K.?

They do. But the U.K. has Barb, which is an independent organization that provides the singular standard for co-viewing measurement that all ad buyers and sellers accept.

There’s still the problem of the co-viewing measurement being projected across the entire market from a smaller panel of viewers, but because it’s one measurement that’s accepted by all parties, there’s less concern about any one party being disproportionately affected.

Hmm. So why doesn’t the U.S. have a Barb?

Why doesn’t the U.S. have a monarchy?

Wut?

The U.S. effectively had a Barb in Nielsen. It was the measurement standard for TV viewership used by ad buyers and sellers as the basis for transactions. But then Nielsen messed up on its measuring during the pandemic, was called out for it, lost its MRC accreditation (which has since been reinstituted) and opened the door for the likes of VideoAmp, Comscore and iSpot.tv to vie to usurp Nielsen’s position as the industry’s primary measurement provider. And now — for as much as Nielsen still dominates the measurement currency market — the industry lives in a multi-currency measurement system akin to the multi-party political system.

Oh-kay… You mentioned MRC being “the industry’s measurement arbiter.” Can’t they do something about this?

Great question. And one I asked Pinelli and MRC CEO and executive director George Ivie.

What’s they say?

They know that co-viewing measurement is imperfect. “We were just talking to a big advertiser earlier this week who was telling us like, this is their biggest source of pain is to try to understand that co-viewing is being applied reasonably everywhere,” said Ivie.

So what are they doing about it?

Nothing just yet. Well, not nothing. They have standards related to co-viewing, like for how audiences can be measured across digital and traditional TV, how audiences can be measured digitally, how data can be combined for measurement and how set-top box data can be collected. But they’re hesitant to set a standard for co-viewing measurement.

Why?

For one thing, MRC doesn’t dictate methodologies, said Ivie. But more to the point, “we haven’t drawn up a standard because what we’re afraid we’re going to do is put a chilling effect on the competitive nature of developing solutions here,”he said.

Meaning what?

Meaning, yes, co-viewing measurement today is imperfect. And yes, that’s a problem. But a bigger problem could be the MRC effectively co-signing one method of measuring co-viewing and constitutionalizing that as a problem for all time. 

Math is hard.

Yup.

What we’ve heard

“My Source News Opinion World.”

— MSNBC’s new name

Numbers to know

100 million: Number of videos that have been created using Google’s generative AI tool Flow.

>100%: Percentage year-over-year increase in the amount of money advertisers and agencies committed to spend on Netflix in this year’s upfront.

-840,000: Number of streaming subscribers that Starz lost in the second quarter of 2025.

What we’ve covered

VTubers are catching marketers’ eyes in 2025:

• VTubers are video creators who use virtual avatars instead of their real-life identities.
• McDonald’s and the Los Angeles Dodgers are among the brands that have sponsored VTubers this year.

Read more about VTubers here.

What we’re reading

YouTube’s Oscar bid:

The Google-owned video platform is interested in replacing Disney’s ABC as the rightsholder for the Academy Awards after Disney’s deal runs out in 2028, according to Bloomberg.

The business of AI slop:

Creators are making thousands of dollars a month through platforms’ ad revenue-sharing programs by uploading loads of low-effort AI-generated videos, according to The Washington Post.

Quibi, part two:

Another weirdly named company run by Hollywood heavyweights is trying to make short-form serialized shows a thing in the U.S. — but with an AI twist — given the format’s popularity abroad, according to The New York Times.

Product placement’s next phase:

Brands have been finagling their wares into Hollywood productions for years, but UTA is looking to address product placement’s biggest obstacle to becoming big business — assessing business impact — through a new in-house product placement department, according to Variety.