Methods and apparatus to generate audience measurement data from population sample data having incomplete demographic classifications

1. A computing system comprising:

at least one processor;

and

a non-transitory computer-readable medium having stored therein instructions that, upon execution by the at least one processor, cause the computing system to:

access first network communications received via a first server associated with an audience measurement entity, the first network communications including first beacon request messages, the first beacon request messages indicating first impressions corresponding to media accessed on devices, the first beacon request messages identifying time segments of the media presented at the devices, the time segments corresponding to site census impression counts;

cause the first server to send second network communications to the devices, the second network communications including first re-direct response messages redirecting the devices to a database proprietor; and

in response to not receiving demographic information corresponding to the time segments of the media, for ones of demographic groups, calculate demographic impression counts based on exposure distribution ratios and the site census impression counts.

2. The computing system of claim 1 , wherein the instructions, upon execution by the at least one processor, further cause the computing system to calculate the demographic impression counts based on ones of the exposure distribution ratios corresponding to ratios of exposures of the media that are attributable to corresponding ones of the demographic groups.

3. The computing system of claim 2 , wherein the instructions, upon execution by the at least one processor, further cause the computing system to determine the exposure distribution ratios based on proportions of exposures attributable to ones of the demographic groups for exposures of the media for which the database proprietor has access to demographic information.

4. The computing system of claim 1 , wherein the instructions, upon execution by the at least one processor, further cause the computing system to calculate a product of the exposure distribution ratios and the site census impression counts to determine the demographic impression counts.

5. The computing system of claim 1 , wherein the instructions, upon execution by the at least one processor, further cause the computing system to calculate demographic durations for ones of the demographic groups based on duration distribution ratios and site census durations.

6. The computing system of claim 5 , wherein instructions, upon execution by the at least one processor, further cause the computing system to calculate the demographic durations based on ones of the duration distribution ratios corresponding to ratios of durations of the media that are attributable to corresponding ones of the demographic groups.

7. The computing system of claim 6 , wherein the instructions, upon execution by the at least one processor, further cause the computing system to determine the duration distribution ratios based on proportions of durations attributable to ones of the demographic groups for durations of exposures to the media for which the database proprietor has access to demographic information.

8. At least one non-transitory computer readable storage medium comprising instructions that, upon execution, cause at least one processor to:

access first network communications received via a first server associated with an audience measurement entity, the first network communications including first beacon request messages, the first beacon request messages indicating first impressions corresponding to media accessed on devices, the first beacon request messages identifying time segments of the media presented at the devices, the time segments corresponding to site census impression counts or site census durations;

cause the first server to send second network communications to the devices, the second network communications including first re-direct response messages redirecting the devices to a database proprietor; and

in response to not receiving demographic information corresponding to the time segments of the media, for ones of demographic groups, calculate demographic impression counts based on exposure distribution ratios and the site census impression counts.

9. The at least one non-transitory computer readable storage medium of claim 8 , wherein the instructions cause the at least one processor to calculate the demographic impression counts based on ones of the exposure distribution ratios corresponding to ratios of exposures of the media that are attributable to corresponding ones of the demographic groups.

10. The at least one non-transitory computer readable storage medium of claim 9 , wherein the instructions cause the at least one processor to determine the exposure distribution ratios based on proportions of exposures attributable to ones of the demographic groups for exposures of the media for which the database proprietor has access to demographic information.

11. The at least one non-transitory computer readable storage medium of claim 8 , wherein the instructions cause the at least one processor to calculate a product of the exposure distribution ratios and the site census impression counts to determine the demographic impression counts.

12. The at least one non-transitory computer readable storage medium of claim 8 , wherein the instructions cause the at least one processor to calculate demographic durations for ones of the demographic groups based on duration distribution ratios and site census durations.

13. The at least one non-transitory computer readable storage medium of claim 12 , wherein instructions cause the at least one processor to calculate the demographic durations based on ones of the duration distribution ratios corresponding to ratios of durations of the media that are attributable to corresponding ones of the demographic groups.

14. The at least one non-transitory computer readable storage medium of claim 13 , wherein the instructions cause the at least one processor to determine the duration distribution ratios based on proportions of durations attributable to ones of the demographic groups for durations of exposures to the media for which the database proprietor has access to demographic information.

15. A method, comprising:

accessing, by executing instructions with at least one processor, first network communications received via a first server associated with an audience measurement entity, the first network communications including first beacon request messages, the first beacon request messages indicating first impressions corresponding to media accessed on devices, the first beacon request messages identifying time segments of the media presented at the devices, the time segments corresponding to site census impression counts;

causing, by executing instructions with the at least one processor, the first server to send second network communications to the devices, the second network communications including first re-direct response messages redirecting the devices to a database proprietor; and

in response not receiving to demographic information corresponding to the time segments of the media, for ones of demographic groups, calculating, by executing instructions with the at least one processor, demographic impression counts based on exposure distribution ratios and the site census impression counts.

16. The method of claim 15 , further including calculating, by executing instructions with the at least one processor, the demographic impression counts based on ones of the exposure distribution ratios corresponding to ratios of exposures of the media that are attributable to corresponding ones of the demographic groups.

17. The method of claim 16 , further including determining, by executing instructions with the at least one processor, the exposure distribution ratios based on proportions of exposures attributable to ones of the demographic groups for exposures of the media for which the database proprietor has access to demographic information.

18. The method of claim 15 , further including calculating, by executing instructions with the at least one processor, a product of the exposure distribution ratios and the site census impression counts to determine the demographic impression counts.

19. The method of claim 15 , further including calculating, by executing instructions with the at least one processor, demographic durations for ones of the demographic groups based on duration distribution ratios and site census durations.

20. The method of claim 19 , further including calculating, by executing instructions with the at least one processor, the demographic durations based on ones of the duration distribution ratios corresponding to ratios of durations of the media that are attributable to corresponding ones of the demographic groups.

21. The method of claim 20 , further including determining, by executing instructions with the at least one processor, the duration distribution ratios based on proportions of durations attributable to ones of the demographic groups for durations of exposures to the media for which the database proprietor has access to demographic information.