15. A computer program product for use in conjunction with a computer system, the computer program product comprising a computer readable storage medium and a computer program mechanism embedded therein, the computer program mechanism comprising: identifying a plurality of source documents including facts associated with a common subject; identifying, from the plurality of source documents, one or more attribute-value pairs associated with the common subject; corroborating a fact, comprising a respective attribute-value pair of the one or more attribute-value pairs associated with the common subject, by determining that the respective attribute-value pair meets one or more predefined corroboration requirements; and in response to corroboration of the fact, updating a status of the respective attribute value pair in a fact repository; wherein corroborating the fact includes: determining that a respective attribute of the respective attribute-value pair meets a first corroboration requirement; and determining that the respective attribute-value pair meets a second corroboration requirement.
15. A computer program product for use in conjunction with a computer system, the computer program product comprising a computer readable storage medium and a computer program mechanism embedded therein, the computer program mechanism comprising: identifying a plurality of source documents including facts associated with a common subject; identifying, from the plurality of source documents, one or more attribute-value pairs associated with the common subject; corroborating a fact, comprising a respective attribute-value pair of the one or more attribute-value pairs associated with the common subject, by determining that the respective attribute-value pair meets one or more predefined corroboration requirements; and in response to corroboration of the fact, updating a status of the respective attribute value pair in a fact repository; wherein corroborating the fact includes: determining that a respective attribute of the respective attribute-value pair meets a first corroboration requirement; and determining that the respective attribute-value pair meets a second corroboration requirement. 18. The computer program product of claim 15 , wherein the second corroboration requirement with respect to the respective attribute-value pair is based on a number of source documents having the respective attribute-value pair associated with the common subject and respective importance metrics of the source documents.