Also, "advertiser" is way too benign a term: in cryptography we generally use "adversary". Consider that in this election season, the Trump and Biden political campaigns will be among the biggest advertisers. Mozilla will sell them information and they will use it. Question: will they only use it to solicit votes, or will they also use it to help round up their enemies if they get into power?
And yes, they can use statistical information for that. The first thing they will want to know about any specific class of enemy is how many of them there are, before worrying about identifying individuals. So Mozilla shouldn't help them with either.
> Mozilla will give them information and they will use it.
Let's just get on the same page about what information the advertisers get. I'll reproduce the paragraph I linked to:
> Since the DAP server acts as a middleman, and reports are only generated at conversion times (impressions without conversions are not reported), ad networks have no way through this method of collecting your personal information (such as your user information or your IP address/browser client info). All they receive is an aggregate that informs them that their ad y (published on source x) led number of people to a positive outcome for their customer over a period of time p. Some amount of noise is also added to the information in order to further strengthen privacy[7].
I'm not aware of how you "round up your enemies" using conversion rate information on websites. It doesn't even tell you how many "specific class of enemy" there is, it's too muddled by the variable of the click rate of the audience.
Not to mention that as state actors I'm sure they would have other, more useful and reliable methods of doing... whatever you're accusing them of doing.
What a pointless bit of FUD in an otherwise fairly rational comment.
For the record, while I think differential privacy is a really cool idea, I also fully support users having the choice to participate or not.
I just don't understand why you see it as invasive, given nothing about you is revealed.
