[semi-extrinsic]

> people who sell stuff think they'll get a higher conversion rate the more targeted they get.... and that's hard to argue with.

Is it really? For me, targeted ads come up for either a) products I have already purchased or b) products I've looked at and then decided not to buy. I got my wife an espresso grinder for Christmas, ordered on Dec. 10, but AdSense is still showing me ads for grinders. There is exactly 0.00% chance of me buying another one.

[dangrossman]

Campaign A: Show 10,000 random people ads for espresso grinders.

Campaign B: Show 10,000 people who recently looked at espresso grinders some ads for them.

95% of the first group didn't know espresso grinders were a thing people bought. The remainder probably aren't actively shopping for one.

In the second group, some portion of the audience has already bought an espresso grinder, or decided they don't want one right now after all. But it's also guaranteed to include thousands of people actively shopping for one right now.

Which campaign do you think is going to result in more espresso grinders sold? The one that doesn't include you, or the one that does?

[oneeyedpigeon]

What about campaign c: show 9,900 people who recently looked at espresso grinders an ad for one, and 100 people who actually bought one an ad for something related that they might need. If you're harvesting that kind of data anyway, at least use it!

As a matter of interest, is someone who has previously purchased an espresso grinder more or less likely to buy one than someone who hasn't?

[ryandvm]

Of course you're correct, but the problem is Campaign C requires a far higher invasion of privacy. Now, not only do you want the advertisers to track the sites you visit - you're also proposing they somehow get information about everything you purchase?! No thanks.

[semi-extrinsic]

It wouldn't be that hard to handle without any further privacy invasion: online shop waits O(12) hours before reporting to AdSense, and if visitor bought the product within that time, reports other, related product instead.

(If the ads in the first 12 hours are important, it makes little sense that they keep advertising for a whole month.)

[mmanfrin]

Your anecdote is not emblematic of the whole. Many people do not immediately buy big ticket items they look at online; but there is data that shows repeated marketing of a product works, and works especially well when the merchant already knows you were looking at a specific product.

Yes, this means they end up wasting ads on people who already purchased, but that is outweighed by the other portion of people who didnt already purchase the product.

[georgyo]

I agree with you, but for a different reason.

I work for a company uses these targeted ADs. 100% of the ADs I see are for what my company sells. Well 98%, sometimes I see ADs for services we are already using.

It would be cool if when I am reading an article about how do X, there was ADs for goods and services that help me do it. That would at least make me think about clicking. Instead, I only see my companies product, which is worse the useless.

My company is paying to advertise to itself. And if it is happening to us, it must be happening to others.

[bduerst]

People who purchase something online are magnitudes more likely to purchase it again than someone who hasn't made the purchase.

[oneeyedpigeon]

Surely it depends on the product - e.g. USB stick versus engagement ring.

[bduerst]

I doubt there is a huge market for online engagement rings, coffins, or other once/twice a lifetime purchases.

For gifting espresso grinders, it's not unlikely that purchasers will buy it as a gift again for their parents, friends, etc.

[ecaradec]

Criteo told in an interview that the click rate was 500% better with their tracking.

[criddell]

What's the gross click rate? If I run a site that has ads on it, almost all visitors have to download and execute kilo- or megabytes of javascript. Very few users click on an ad.

When an ad impression leads to a sale of something, that's great for that user and the vendor. But how many megabytes of javascript was downloaded and executed by all the users that saw the ad and didn't buy anything? The burden on the rest of us to support those two parties seems excessive.