Methods and apparatus to determine media impressions using distributed demographic information

A non-transitory computer readable medium comprising instructions to cause programmable circuitry to at least:

• log, at a first Internet domain, a first record for a first website visit by a first client device to a website at a second Internet domain, the first record based on a hypertext transfer protocol (HTTP) request, the first record including a timestamp, a site identifier, and a user identifier, the timestamp representative of a time of the first website visit, the site identifier corresponding to the web site at the second Internet domain;
• and
• weight impression data in a report, the impression data representative of impressions of advertisements associated with the first record and with second records, the second records corresponding to second website visits to the website via second client devices, the weighting of the impression data based on demographic distributions of audience members corresponding to the first and second records.

A method comprising:

• logging, by executing a first instruction with programmable circuitry at a first Internet domain, a first record for a first website visit by a first client device to a website at a second Internet domain, the first record based on a hypertext transfer protocol (HTTP) request, the first record including a timestamp, a site identifier, and a user identifier, the timestamp representative of a time of the first website visit, the site identifier corresponding to the website at the second Internet domain;
• and
• weighting, by executing a second instruction with the programmable circuitry, impression data in a report, the impression data representative of impressions of advertisements associated with the first record and with second records, the second records corresponding to second website visits to the website via second client devices, the weighting of the impression data based on demographic distributions of audience members corresponding to the first and second records.