5 ms·

OP says they have different email addresses for Amazon and FB. How would Amazon know which user to target ads on FB in this case?

thisismine 9y ago
Cookie is a thing.
- ars 9y ago
  It's not cookie, it happens across different browsers. It's IP based.
  - dbbk 9y ago
    How could IP-based possibly work for people at places like college campuses?
    - Jasamba 9y ago
      They take the number of people from the same IP into account. IPs are broken down into public IPs vs private IPs based on traffic/timing of usage etc. There are research papers on this sort of feature contruction using only IPs. Cross device especially uses it extensively to be able to probabilistically ascertain if the person from your house who is checking their phone is the same person who checked smth on the Desktop computer last night based on your online timing, IPs, behaviour over the day. They can figure out, for instance, your office vs home browsing timing, interests etc with the same methods.
      - hyades 9y ago
        Interesting. Do you have the links of these papers so that I can read more?
  - tarboreus 9y ago
    It's probably not cookie-based, or not only cookie-based. Browser fingerprinting and user profiling have gotten very sophisticated, and don't think the big 4.5 aren't using these techniques extensively.
  - nl 9y ago
    It's probably still cookie based. If one logged into Amazon in both browsers then it is really just linking to the account (even after logging out).
- darylfritz 9y ago
  OP also said they used two completely different browsers
  - hakcermani 9y ago
    From the same network ? If both browsers are from different computers (worse still from same computer) from same network then the externally visible ip address is the same isn't it ?
howderek 9y ago
Amazon customers connect their Facebook friends to find people with wishlists. Someone who has the contact could have information that could link the two accounts, for instance if the OP has someone in their friends' wishlists and they have someone with OP's name in theirs. Or could be connected to a subsidiary like IMDb.

thisismine 9y ago

Cookie is a thing.

ars 9y ago
It's not cookie, it happens across different browsers. It's IP based.
- dbbk 9y ago
  How could IP-based possibly work for people at places like college campuses?
  - Jasamba 9y ago
    They take the number of people from the same IP into account. IPs are broken down into public IPs vs private IPs based on traffic/timing of usage etc. There are research papers on this sort of feature contruction using only IPs. Cross device especially uses it extensively to be able to probabilistically ascertain if the person from your house who is checking their phone is the same person who checked smth on the Desktop computer last night based on your online timing, IPs, behaviour over the day. They can figure out, for instance, your office vs home browsing timing, interests etc with the same methods.
    - hyades 9y ago
      Interesting. Do you have the links of these papers so that I can read more?
- tarboreus 9y ago
  It's probably not cookie-based, or not only cookie-based. Browser fingerprinting and user profiling have gotten very sophisticated, and don't think the big 4.5 aren't using these techniques extensively.
- nl 9y ago
  It's probably still cookie based. If one logged into Amazon in both browsers then it is really just linking to the account (even after logging out).
darylfritz 9y ago
OP also said they used two completely different browsers
- hakcermani 9y ago
  From the same network ? If both browsers are from different computers (worse still from same computer) from same network then the externally visible ip address is the same isn't it ?

howderek 9y ago

Amazon customers connect their Facebook friends to find people with wishlists. Someone who has the contact could have information that could link the two accounts, for instance if the OP has someone in their friends' wishlists and they have someone with OP's name in theirs. Or could be connected to a subsidiary like IMDb.