A mechanism is provided in a question answering system for duration similarity weighting in a question answering system. The question answering system receives an input question. The question answering system generates a plurality of candidate answers to the input question using a corpus of information. The question answering system identifies a question-side duration value for the input question and identifies a policy-side duration value for a policy to be applied to an entity identified in the input question. The question answering system determines a duration similarity weight for each of the plurality of candidate answers. The question answering system applies the duration similarity weight to each of the plurality of candidate answers. The question answering system ranks the plurality of candidate answers and outputs one or more of the candidate answers.
Please help me write a proper abstract based on the patent claims. CLAIM: 1. A method, in a data processing system, for duration similarity weighting in a question answering system, the method comprising: receiving an input question concerning an entity; generating a plurality of candidate answers to the input question using a corpus of information; identifying a question-side duration value for the entity identified in the input question; identifying a policy-side duration value for a policy applied to the entity to generate each of the plurality of candidate answers; determining a duration similarity weight for each of the plurality of candidate answers based on a similarity between the question-side duration value and the policy-side duration value; applying the duration similarity weight of the plurality of candidate answers; ranking the plurality of candidate answers based on applying the duration similarity weight to each of the plurality of candidate answers; and outputting one or more of the candidate answers based on the ranking. 2. The method of claim 1, wherein applying the duration similarity weight to each of the plurality of candidate answers comprises; determining a confidence score for each given candidate answer; and multiplying the duration similarity weight of the given candidate answer by the confidence score of the given candidate answer to form a duration similarity weighted confidence score. 3. The method of claim 2, wherein ranking the plurality of candidate answers comprises ranking the plurality of candidate answers according to duration similarity weighted confidence score. 4. The method of claim 1, wherein identifying the question-side duration value for the input question comprises identifying the question-side duration value within text of the input question. 5. The method of claim 1, wherein identifying the question-side duration value for the input question comprises: identifying question-side support evidence from the corpus of information for the input question; and identifying the question-side duration value within the question-side support evidence. 6. The method of claim 1, wherein identifying the policy-side duration value comprises: identifying policy-side support evidence for the to be applied to the entity identified in the input question; and identifying the policy-side duration value within the policy-side support evidence. 7. The method of claim 1, wherein determining the duration similarity weight for a given candidate answer comprises calculating the duration similarity weight, similarity, using the following equation: similarity = min  ( x , y ) max  ( x , y )  ( e - ( x - y ) 2 2  μ 2 ) , where x is the question-side duration value, y is the policy-side duration value, and μ = ( x + y ) 2 . 8. The method of claim 1, wherein determining the duration similarity weight for a given candidate answer comprises calculating the duration similarity weight, similarity, using the following equation: similarity = min  ( x , y ) max  ( x , y )  ( e - ( x - y ) 2 2  μ 2 ) , where x is the question-side duration value and y is the policy-side duration value. 9.-20. (canceled)