| 摘要 |
A panel provider may transmit queries to an audience measurement server to retrieve measurement data for subsets of clients selected via one or more characteristics, such as characteristics of the client, characteristics of the client's device, characteristics of the received content, etc. To protect panel data, the panel provider need not identify these characteristics to the audience measurement server; rather, queries may be made via a plurality of filters that may be applied to client and/or content identifiers. Because the audience measurement server may apply the filters or data structures to select client data for retrieval without knowing what the filter represents, the panel provider's reason for any particular query may be hidden. For further obfuscation, the panel provider may provide a plurality of filters that individually may identify large numbers of clients, but when intersected or applied together, identify only the clients for whom measurement data is required. |
