8. A computer program product stored in a computer readable storage medium, comprising computer instructions that, when executed by an information handling system, causes the information handling system to perform actions comprising: ingesting a first set of sources into a first corpus; ingesting a second set of sources into a second corpus, wherein the second set of sources are a subset of the first set of sources, and wherein the second set of sources include updates to the first set of sources; receiving a question from a requestor; identifying a plurality of candidate answers to the question using one or more sources included in the first and second corpuses, wherein a weighting is associated with each of the candidate answers; determining whether the first and second corpuses have an overlapping source from which two or more of the candidate answers were identified; in response to determining the overlapping source, assigning a first candidate answer from the overlapping source in the first corpus with a lower weighting than a second candidate answer from the overlapping source in the second corpus; selecting one or more likely answers from the plurality of candidate answers, wherein the selecting is based on the weighting associated with the respective candidate answers; and returning the selected likely answers to the requestor.
8. A computer program product stored in a computer readable storage medium, comprising computer instructions that, when executed by an information handling system, causes the information handling system to perform actions comprising: ingesting a first set of sources into a first corpus; ingesting a second set of sources into a second corpus, wherein the second set of sources are a subset of the first set of sources, and wherein the second set of sources include updates to the first set of sources; receiving a question from a requestor; identifying a plurality of candidate answers to the question using one or more sources included in the first and second corpuses, wherein a weighting is associated with each of the candidate answers; determining whether the first and second corpuses have an overlapping source from which two or more of the candidate answers were identified; in response to determining the overlapping source, assigning a first candidate answer from the overlapping source in the first corpus with a lower weighting than a second candidate answer from the overlapping source in the second corpus; selecting one or more likely answers from the plurality of candidate answers, wherein the selecting is based on the weighting associated with the respective candidate answers; and returning the selected likely answers to the requestor. 12. The computer program product of claim 8 wherein the actions further comprise: associating an input date corresponding to each of the first and second set of sources, wherein the assigning of the lower weighting to the overlapping source in the first source is also based on the input date of the overlapping source in the first corpus being earlier than the input date of the overlapping source in the second corpus.