How on earth does Facebook / ebay do this?

[Jader1973]

I know from a couple of talks from the Marketing bods at work that Facebook is very invasive in terms of the data they can get from it e.g. if you are looking at various types of product or one specific product thus allowing them to tailor the ads they push to the user.

Today something really odd happened.

I was on the PC earlier looking at tat on ebay. After that I went on my phone and on to Facebook - a suggested post is ebay and ads for what I was looking at earlier on the PC. Exactly what I was looking for earlier on the PC, as in identical.

Facebook on the phone is permanently signed in, I also have the ebay ap on my phone but it was not signed in, and I wasn't signed in to ebay on the PC.

Is ebay doing some sort cross reference and pushing the ad through Facebook? If they are, how do the know the phone belongs to the person who used the PC? Is it guessing based on who last logged in to ebay on both devices?

[PurpleMoonlight]

Cookies.

[Alucidnation]

And special magic.

[anonymous-user]

Try talking around your phone about various things you might like to buy/places you would like to visit and see them pop up as Facebook ads. Either massive coincidence or the app is listening through the phone.

[MyVTECGoesBwaaah]

Being signed into Chrome on both devices could cause this - or Chrome and Android.

[bananachips]

To make muddy the waters even this happened to me. I was telling colleagues in tje work I made deer antlers into candle holders for folk over Christmas and that if I could more I would probably like to try and sell them online. Then not long after one of the adverts on Facebook was how to help and start selling things online...
I wasn't surprised im the slightest just pissed off. Heard of it happen before but didn't believe it but they're always listening too.

[Jader1973]

I understand cookies but aren’t they stored on the actual device?

How does the Ebay on the phone know what I was looking at on EBay on the PC if I wasn’t signed in to my account? Does it cross check user IDs and cookies and send info to other devices that have used that same ID?

[durbster]

If you want to advertise with Facebook you add a little bit of code to your website that tracks the visitors and traces them back to their Facebook profile. The idea is that you can use that information to get a better understanding of who your audience is.

It's called Facebook Pixel:
https://www.facebook.com/business/help/95219235484...

Google have something similar and I imagine eBay does too.

If you visit any product website now, there will probably be dozens of tracking scripts on there. If you want to see for yourself:
1. Open developer tools (F12 in Chrome)
2. Click on the Network tab
3. Go to a website

Aside from the the files required to load the page, you'll also usually see hundreds of little snippets of information being fired off to various tracking services. There aren't many e-commerce sites that don't do this nowadays.

These can be blocked up to a point but they're very sophisticated.

[Alex@POD]

Jader1973 said:

I understand cookies but aren’t they stored on the actual device?

How does the Ebay on the phone know what I was looking at on EBay on the PC if I wasn’t signed in to my account? Does it cross check user IDs and cookies and send info to other devices that have used that same ID?

As someone mentioned above, if you are using Chrome and/or Android there's a fair chance you're signed in to both, and cookies can be stored in "the cloud" in that respect.

You'll see targeted adverts on most sites too, not just eBay.

[Evolved]

You’re logged in automatically on both devices so tracks usage based on cookies and links the user accounts.

[LordGrover]

durbster said:

If you want to advertise with Facebook you add a little bit of code to your website that tracks the visitors and traces them back to their Facebook profile. The idea is that you can use that information to get a better understanding of who your audience is.

It's called Facebook Pixel:
https://www.facebook.com/business/help/95219235484...

Google have something similar and I imagine eBay does too.

If you visit any product website now, there will probably be dozens of tracking scripts on there. If you want to see for yourself:
1. Open developer tools (F12 in Chrome)
2. Click on the Network tab
3. Go to a website

Aside from the the files required to load the page, you'll also usually see hundreds of little snippets of information being fired off to various tracking services. There aren't many e-commerce sites that don't do this nowadays.

These can be blocked up to a point but they're very sophisticated.

Interesting. Ta.

[Jader1973]

Not using Android or Chrome (iPhone and IE) and wasn’t signed in to Ebay on either device. I only ever use Facebook on the phone.

AllI can think of is that it must be something in Ebay that tracks what is being viewed on a device and pushes the info to any other device that has used the account that was last signed in even if the user isn’t signed in. Or something.

[alistair1234]

The worst is where you don't even search for it but it hears you talking about it and then gives you an ad. Happened to me a few times, always seems to be for Birra Moretti and San Peligrino drinks. I would never search for them, its not like you need to look at them like something on amazon, its purely from my saying to the GF to get some.

[red_slr]

My watch is always listening, no idea how it funnels the data back down the chain but I regularly get adverts for stuff we have been talking about at total random. The last one was Victoria secrets!!!!

[Scabutz]

Jader1973 said:

Not using Android or Chrome (iPhone and IE) and wasn’t signed in to Ebay on either device. I only ever use Facebook on the phone.

AllI can think of is that it must be something in Ebay that tracks what is being viewed on a device and pushes the info to any other device that has used the account that was last signed in even if the user isn’t signed in. Or something.

The adds come from a 3rd party source, not FB or Ebay. Its the system that provides the adds that is placing the cookies which they can then read and then target adds at you. Think of it like walking into a shop looking at something, a 3rd party person sees you, then follows you round into other shops telling you should go back and buy the thing you first looked at.

Also if you are logged into Chrome and sites use things like Google Analytics and Facebook Pixel they will know you better than your own mother.

[CrutyRammers]

Jader1973 said:

Not using Android or Chrome (iPhone and IE) and wasn’t signed in to Ebay on either device. I only ever use Facebook on the phone.

AllI can think of is that it must be something in Ebay that tracks what is being viewed on a device and pushes the info to any other device that has used the account that was last signed in even if the user isn’t signed in. Or something.

Sort of that. Every time you browse their site, you'll send a unique id which identifies the device and / or user. That's stored in a cookie on the device, but sent up with every request to their server. They record that ID against everything you look up. Over time, they can match up users with devices (eg if you sign in to ebay on a machine once, it'll remember that you use that machine, even if you're not signed in next time). Then when you browse a site with their adverts on, the unique ID from the device is sent up, they go, "Ah ha, that's Jader1973, he likes looking at <whatever>", and sends back adverts for <whatever>.

[Jader1973]

Scabutz said:

The adds come from a 3rd party source, not FB or Ebay. Its the system that provides the adds that is placing the cookies which they can then read and then target adds at you. Think of it like walking into a shop looking at something, a 3rd party person sees you, then follows you round into other shops telling you should go back and buy the thing you first looked at.

Also if you are logged into Chrome and sites use things like Google Analytics and Facebook Pixel they will know you better than your own mother.

I remember Marketing mentioning Google analytics too. That was both interesting and terrifying!

[Planet Claire]

alistair1234 said:

The worst is where you don't even search for it but it hears you talking about it and then gives you an ad. Happened to me a few times, always seems to be for Birra Moretti and San Peligrino drinks. I would never search for them, its not like you need to look at them like something on amazon, its purely from my saying to the GF to get some.

Just go into Apps, select Chrome (or whatever app) and under permissions deselect the option for the microphone.

[tankplanker]

The majority of users have a unique fingerprint that will help identify you even if you have never signed into Google, Facebook or some other overarching account even across multiple devices. Even if you never login to Facebook it'll still install "cookies" (cookies do not cover the half of how they are tracking these days) that will track you across your entire browsing session.

Test it with this: https://panopticlick.eff.org/

[Jader1973]

CrutyRammers said:

Sort of that. Every time you browse their site, you'll send a unique id which identifies the device and / or user. That's stored in a cookie on the device, but sent up with every request to their server. They record that ID against everything you look up. Over time, they can match up users with devices (eg if you sign in to ebay on a machine once, it'll remember that you use that machine, even if you're not signed in next time). Then when you browse a site with their adverts on, the unique ID from the device is sent up, they go, "Ah ha, that's Jader1973, he likes looking at <whatever>", and sends back adverts for <whatever>.

That makes sense. So in reality clearing your cookies is a waste of time because they have already passed everything back to the servers, which are busy creating a profile.