5. The computer-implemented method of claim 3 , wherein inserting the search result identifying the second resource in the set of search results identifying the first resources comprises: determining an insertion score based, in part, on the search probability ratio, wherein the insertion score defines an ordinal insertion position at which a second resource search result referencing the second resource is to be inserted into a ranking of first resource search results referencing the first resources; and generating a search results resource for displaying the first resource search results according to their respective ordinal positions in the ranking and the second resource search results at the ordinal insertion position.
5. The computer-implemented method of claim 3 , wherein inserting the search result identifying the second resource in the set of search results identifying the first resources comprises: determining an insertion score based, in part, on the search probability ratio, wherein the insertion score defines an ordinal insertion position at which a second resource search result referencing the second resource is to be inserted into a ranking of first resource search results referencing the first resources; and generating a search results resource for displaying the first resource search results according to their respective ordinal positions in the ranking and the second resource search results at the ordinal insertion position. 6. The computer-implemented method of claim 5 , wherein determining an insertion score based, in part, on the search probability ratio comprises: determining an insertion score corresponding to a first ordinal position when the search probability ratio meets a first insertion threshold; determining an insertion score corresponding to a second ordinal position when the search probability ratio meets a second insertion threshold but does not meet the first insertion threshold; and determining an insertion score corresponding to a third ordinal position when the search probability ratio meets a third insertion threshold but does not meet the second insertion threshold.