Implicit Durations Calculation and Similarity Comparison in Question Answering Systems

A method, in a data processing system comprising a processor and a memory, for performing a duration-based operation, the method comprising:

• receiving, by the data processing system, at least one document having a plurality of associated dates and/or times and concepts associated with the dates and/or times, wherein the at least one document does not explicitly specify a duration between the dates and/or times;
• correlating, by the data processing system, dates and/or times in the at least one document having similar associated concepts;
• calculating, by the data processing system, for the correlated dates and/or times, an implicit duration based on the dates and/or times;
• associating, by the data processing system, the associated concepts with the implicit duration;
• annotating, by the data processing system, a first document in the at least one document with an implicit duration annotation that specifies the implicit duration and the associated concepts;
• and
• performing, by the data processing system, the duration-based operation based on the implicit duration annotation.