11. A computer program product comprising a non-transitory computer readable medium having a computer readable program stored therein, wherein the computer readable program, when executed on a computing device, causes the computing device to: receive a request for data, wherein the request specifies a relational context corresponding to a selected group of selected persons selected from a global group of persons based on the relational context, and wherein the relational context specifies one or more attributes of selected persons in the selected group that establishes a relationship between the selected persons and distinguishes the selected persons from non-selected persons in the global group that are not in the selected group; determine, for the relational context corresponding to the selected group, based on a corpus of personal information data corresponding to the selected persons in the selected group, one or more key attributes in the personal information data; determine a rarity value for each key attribute of the one or more key attributes within the relational context of the selected group; and anonymize selected key attributes in the one or more key attributes based on the determined rarity value for each of the key attributes within the relational context of the selected group, wherein the computer readable program causes the computing device to determine the rarity value of each key attribute of the one or more key attributes at least by generating a relative rarity matrix data structure that identifies the one or more key attributes and their corresponding related relative rarity measures.
11. A computer program product comprising a non-transitory computer readable medium having a computer readable program stored therein, wherein the computer readable program, when executed on a computing device, causes the computing device to: receive a request for data, wherein the request specifies a relational context corresponding to a selected group of selected persons selected from a global group of persons based on the relational context, and wherein the relational context specifies one or more attributes of selected persons in the selected group that establishes a relationship between the selected persons and distinguishes the selected persons from non-selected persons in the global group that are not in the selected group; determine, for the relational context corresponding to the selected group, based on a corpus of personal information data corresponding to the selected persons in the selected group, one or more key attributes in the personal information data; determine a rarity value for each key attribute of the one or more key attributes within the relational context of the selected group; and anonymize selected key attributes in the one or more key attributes based on the determined rarity value for each of the key attributes within the relational context of the selected group, wherein the computer readable program causes the computing device to determine the rarity value of each key attribute of the one or more key attributes at least by generating a relative rarity matrix data structure that identifies the one or more key attributes and their corresponding related relative rarity measures. 19. The computer program product of claim 11 , wherein anonymizing selected key attributes in the one or more key attributes based on the determined rarity value for each of the key attributes within the relational context of the selected group comprises replacing the selected key attributes with generalized attributes specified in a generalization table data structure.