6. A system having at least one processor storage, and a communication platform for evaluating query suggestion quality, the system comprising: a search serving engine configured to provide a plurality of query suggestions in a ranking to a user; a user activity detecting unit configured to detect a selection of one of the plurality of query suggestions, wherein the selection causes modification of the position of the selected query suggestion in the ranking; a suggestion position determining unit configured to determine a position of the selected one of the plurality of query suggestions in the ranking; and a scoring unit configured to calculate a quality measure of the plurality of query suggestions based, at least in part, on the selection and the position of the selected one of the plurality of query suggestions, wherein the plurality of query suggestions in the ranking are provided to a plurality of users; and wherein the quality measure of the plurality of query suggestions is determined based on a total number of query suggestions in the plurality of query suggestions whose positions are modified in response to the selection.
6. A system having at least one processor storage, and a communication platform for evaluating query suggestion quality, the system comprising: a search serving engine configured to provide a plurality of query suggestions in a ranking to a user; a user activity detecting unit configured to detect a selection of one of the plurality of query suggestions, wherein the selection causes modification of the position of the selected query suggestion in the ranking; a suggestion position determining unit configured to determine a position of the selected one of the plurality of query suggestions in the ranking; and a scoring unit configured to calculate a quality measure of the plurality of query suggestions based, at least in part, on the selection and the position of the selected one of the plurality of query suggestions, wherein the plurality of query suggestions in the ranking are provided to a plurality of users; and wherein the quality measure of the plurality of query suggestions is determined based on a total number of query suggestions in the plurality of query suggestions whose positions are modified in response to the selection. 8. The system of claim 6 , wherein the quality measure is determined based, at least in part, on bias information associated with the one of the plurality of query suggestions.