25. 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 using ad scores of the ads when the ads are served with the document and ad scores of the ads when the ads are served across a collection of documents to generate a document score, 2) accepting a cost for an action with respect to an ad when the ad is served with the document, and 3) adjusting the cost using the document score to generate a modified cost.
25. 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 using ad scores of the ads when the ads are served with the document and ad scores of the ads when the ads are served across a collection of documents to generate a document score, 2) accepting a cost for an action with respect to an ad when the ad is served with the document, and 3) adjusting the cost using the document score to generate a modified cost. 27. The apparatus of claim 25 wherein each of the ad scores indicates a return on investment for an ad selection.