35. Apparatus comprising: a) at least one processor; b) an input for accepting ad scores wherein each of the ad scores indicates a value of a user selection of an ad; and c) at least one storage device storing a computer executable code which, when executed by the at least one processor, performs a method of 1) scoring a document set including at least two documents using ad scores of the ads when the ads are served with the document set and ad scores of the ads when the ads are served across a collection of document sets to generate a document set score, 2) accepting a cost for an action with respect to an ad when the ad is served with a document of the document set, 3) adjusting the cost using the document set score to generate a modified cost.
35. Apparatus comprising: a) at least one processor; b) an input for accepting ad scores wherein each of the ad scores indicates a value of a user selection of an ad; and c) at least one storage device storing a computer executable code which, when executed by the at least one processor, performs a method of 1) scoring a document set including at least two documents using ad scores of the ads when the ads are served with the document set and ad scores of the ads when the ads are served across a collection of document sets to generate a document set score, 2) accepting a cost for an action with respect to an ad when the ad is served with a document of the document set, 3) adjusting the cost using the document set score to generate a modified cost. 44. The apparatus of claim 35 wherein the document set is a Website.