Despite standards, viewability measurements done by "black box" vendors are not reliable because they cannot be independently verified for accuracy. Marketers should DIY (do it yourself) using standard browser javascript code to double check if the measurements from the vendors are even close. With published estimates of viewability in the 60 - 80% range, it is likely very far off. Look at the directly measured data in the following charts and see for yourself what correctly measured viewability looks like.

1. March 2019 / Page 0marketing.scienceconsulting group, inc.
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Correctly Measured
Viewability - DIY
March 2019
Augustine Fou, PhD.
acfou [at] mktsci.com
212. 203 .7239

2. March 2019 / Page 1marketing.scienceconsulting group, inc.
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“Actual viewability may be lower
than you think. You should measure
it yourself to double-check and it
should be measured in-ad.”

3. March 2019 / Page 2marketing.scienceconsulting group, inc.
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(2018) Code to alter viewability
“the [malicious] code used by
NMG is designed to interfere
with the ability of third-party
measurement systems to
determine how much of a
digital ad was viewable during
a browsing session.
This code manipulated
data to ensure that
otherwise unviewable
ads showed up in
measurement systems as
valid impressions, which
resulted in payment being
made for the ad.”
Buzzfeed, March 2018

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Here’s how to measure it yourself
and verify the data you are given.

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Viewability Measurement Notes
Direct measurement is necessary, measurement done in-ad
• Viewability must be measured in-ad. On-site measurements are
also valid, and this can be corroborated by analyzing the page
layout – where the ad slots are arrayed on the page.
• Desktop and mobile web are similar since browsers are standard;
but app impressions must be separated out because measurement
reliability in-app is low;
• Scrolling in mobile means actual viewability is very low
• Things should add up to be 100% (internal data consistency)
visibilityState
(is browser minimized
or tab active?)
intersection
(is the ad slot in
the viewport?)
viewable = x

6. March 2019 / Page 5marketing.scienceconsulting group, inc.
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Campaign 1 - B2C
Programmatic media – desktop, mobile, app
desktop
only
mobile
web only app only
hasFocus:1 4.2% 8% 0.2% 1% 0.1% 0%
-hasFocus:1 47.9% 92% 37.2% 99% 10.5% 100%
52.1% 37.4% 10.5% 100.0%
visibilityState:visible 41.2% 79% 37.0% 99% 6.9% 65%
-visibilityState:visible 10.9% 21% 0.4% 1% 3.7% 35%
52.1% 37.4% 10.5% 100.0%
intersection >50% 18.1% 35% 1.4% 4% 2.3% 22%
-intersection >50% 34.0% 65% 36.0% 96% 8.2% 78%
52.1% 37.4% 10.5% 100.0%
measured viewable 18% 1% 2%

7. March 2019 / Page 6marketing.scienceconsulting group, inc.
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Campaign 2 - B2C
Programmatic media – desktop, mobile, app
desktop
only
mobile
web only app only
hasFocus:1 1.9% 3% 6.0% 28% 0.4% 2%
-hasFocus:1 56.3% 97% 15.5% 72% 20.0% 98%
58.2% 21.5% 20.3% 100.0%
visibilityState:visible 37.1% 64% 19.4% 91% 17.8% 88%
-visibilityState:visible 21.1% 36% 2.0% 9% 2.5% 12%
58.2% 21.5% 20.3% 100.0%
intersection >50% 13.0% 22% 2.3% 11% 14.4% 71%
-intersection >50% 45.3% 78% 19.2% 89% 5.9% 29%
58.2% 21.5% 20.3% 100.0%
measured viewable 12% 2% 4%

8. March 2019 / Page 7marketing.scienceconsulting group, inc.
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Campaign 3 - B2C
Programmatic media – more desktop, mobile, app
desktop
only
mobile
web only app only
hasFocus:1 1.5% 2% 0.1% 1% 0.0% 0%
-hasFocus:1 73.0% 98% 13.1% 99% 12.3% 100%
74.4% 13.2% 12.3% 100.0%
visibilityState:visible 41.1% 55% 12.8% 97% 10.1% 82%
-visibilityState:visible 33.3% 45% 0.5% 3% 2.2% 18%
74.4% 13.2% 12.3% 100.0%
intersection >50% 17.3% 23% 0.9% 7% 3.9% 32%
-intersection >50% 57.2% 77% 12.3% 93% 8.4% 68%
74.5% 13.3% 12.3% 100.0%
measured viewable 15% 1% 4%

9. March 2019 / Page 8marketing.scienceconsulting group, inc.
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Campaign 4 - B2C
Programmatic media – desktop, mobile, more app
desktop
only
mobile
web only app only
hasFocus:1 1.0% 3% 2.1% 7% 0.0% 0%
-hasFocus:1 32.3% 97% 26.6% 93% 38.0% 100%
33.3% 28.7% 38.0% 100.0%
visibilityState:visible 23.7% 71% 28.2% 98% 36.0% 95%
-visibilityState:visible 9.7% 29% 0.5% 2% 2.0% 5%
33.3% 28.7% 38.0% 100.0%
intersection >50% 12.6% 38% 2.8% 10% 30.6% 81%
-intersection >50% 20.7% 62% 25.9% 90% 7.4% 19%
33.3% 28.7% 38.0% 100.0%
measured viewable 12% 3% 3%

10. March 2019 / Page 9marketing.scienceconsulting group, inc.
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Campaign 5 – RON, 1c CPM
Programmatic media – desktop, heavy mobile, no app
desktop
only
mobile
web only app only
hasFocus:1 0.1% 1% 0.1% 0% 0.0% 0%
-hasFocus:1 22.1% 99% 77.5% 100% 0.2% 100%
22.2% 77.6% 0.2% 100.0%
visibilityState:visible 6.0% 27% 75.2% 97% 0.1% 58%
-visibilityState:visible 16.3% 73% 2.4% 3% 0.1% 42%
22.2% 77.6% 0.2% 100.0%
intersection >50% 3.4% 15% 1.5% 2% 0.1% 56%
-intersection >50% 18.8% 85% 76.0% 98% 0.1% 44%
22.2% 77.6% 0.2% 100.0%
measured viewable 3% 2% 0%

11. March 2019 / Page 10marketing.scienceconsulting group, inc.
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Exchange 1
Programmatic media – desktop, mobile, app
desktop
only
mobile
web only app only
hasFocus:1 4.5% 8% 0.0% 0% 0.0% 0%
-hasFocus:1 54.8% 92% 27.9% 100% 12.8% 100%
59.3% 28.0% 12.8% 100.0%
visibilityState:visible 42.4% 71% 26.9% 96% 11.2% 88%
-visibilityState:visible 16.9% 29% 1.1% 4% 1.5% 12%
59.3% 28.0% 12.8% 100.0%
intersection >50% 16.5% 28% 4.8% 17% 4.7% 37%
-intersection >50% 42.8% 72% 23.1% 83% 8.1% 63%
59.3% 28.0% 12.8% 100.0%
measured viewable 16% 5% 5%

12. March 2019 / Page 11marketing.scienceconsulting group, inc.
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Exchange 2
Programmatic media – desktop, mobile, app
desktop
only
mobile
web only app only
hasFocus:1 0.5% 1% 0.0% 0% 0.0% 0%
-hasFocus:1 84.7% 99% 9.7% 100% 5.0% 100%
85.3% 9.7% 5.0% 100.0%
visibilityState:visible 31.7% 37% 9.0% 93% 4.6% 92%
-visibilityState:visible 53.5% 63% 0.7% 7% 0.4% 8%
85.2% 9.7% 5.0% 100.0%
intersection >50% 9.4% 11% 1.0% 10% 0.7% 13%
-intersection >50% 75.9% 89% 8.8% 90% 4.4% 87%
85.2% 9.7% 5.0% 100.0%
measured viewable 9% 1% 1%

13. March 2019 / Page 12marketing.scienceconsulting group, inc.
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Viewability vs Ad Blocking
Measurement accuracy depends on a number of factors
Viewability Ad Blocking
• Is dependent on the page
layout, where the ad is
• Must be measured in-ad;
direct measurement is key
• In-app impressions must be
separated out; desktop and
mobile web are similar
• Is related to the browser/
tech used by the user
• Must be measured on-site;
direct measurement is key
• Desktop must be separated
from mobile
• Bots should be excluded, %
of data not measurable
should be disclosed

14. March 2019 / Page 13marketing.scienceconsulting group, inc.
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About the Author
Augustine Fou, PhD.
acfou [@] mktsci.com
212. 203 .7239

15. March 2019 / Page 14marketing.scienceconsulting group, inc.
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Dr. Augustine Fou – Researcher
2013
2014
Published slide decks and posts:
http://www.slideshare.net/augustinefou/presentations
https://www.linkedin.com/today/author/augustinefou
2016
2015
2017
20192018