[kulahan]

Google in general have been resistant to letting anyone see how effective their ads truly are - and most studies that get close tend to show extremely questionable efficacy results.

If Google shows everyone how ineffective ads actually are, they’d crumble.

[jefftk]

This is very much not true: Google has a bunch of options for measuring ad effectiveness, and when I was there (until three years ago) it was very hard to get advertisers to use them.

The two main options advertisers have are:

* Brand Lift Studies: split audience into treatment and control, use surveys on a small fraction of participants to measure impact

* Conversion Lift: again split audience into treatment and control, compare downstream actions like purchases ("conversions")

These both work on YouTube IIRC.

[kulahan]

I am not surprised google has many tools to tell you how great google is doing at using google's data for you.

Anyways, I was mostly referring to sales at physical locations; I assume it's pretty viable to build a system to figure out if someone who previously bought a lot of shein is now buying a lot of temu.

[jefftk]

If Google didn't want people to see "ineffective ads actually are" why would they build and push Brand Lift Studies and Conversion Lift?

Offline purchases are harder, of course, but pretty sure you can still do this: https://support.google.com/google-ads/answer/9994849

[kulahan]

For the same reason I would show someone a “totally real and honest” screenshot of my company’s finances for some quick cash. Doubly true if there’s effectively no way to be caught.

[jefftk]

Is your claim that these studies are incapable of measuring what advertisers actually care about? That Google is reporting fraudulently positive results? Something else?

(Once I understand your claim I'll be better able to respond: I think "there's effectively no way to be caught" is not true under both of the interpretations I see)

[lurk2]

> and most studies

Such as?