16. A non-transitory computer-readable medium having instructions stored thereon for execution by at least one processing circuit to rank relevance of parameters of a content item, the instructions comprising: receiving a plurality of parameters of a content item and a plurality of corresponding initial relevance scores of the parameters indicating relevance of the parameters to the content item; estimating, using a statistical model, a plurality of revised relevance scores from the initial relevance scores, wherein each of the revised relevance scores is a function of at least two of the plurality of initial relevance scores; and ranking the plurality of parameters based on the revised relevance scores.
17. The non-transitory computer-readable medium of claim 16 , wherein the instructions further comprise: receiving data indicative of actual ranking of parameters of a plurality of content items; and training the statistical model using the data.