17. The one or more memory devices of claim 16 , further comprising determining that the first entity was previously extracted from the first search query received from the user.
17. The one or more memory devices of claim 16 , further comprising determining that the first entity was previously extracted from the first search query received from the user. 18. The one or more memory devices of claim 17 , further comprising determining a confidence interval representing a likelihood that the user is engaging in a comparison task when the user submits the second search query, wherein the confidence interval is calculated based on a history of the user's search activities pertaining to the first entity.