I know this is probably a stretch, but has anyone seen any studies/articles regarding post impression data for keyword Search Engine Marketing (Google, Overture, etc.)? I'm trying to apply additional benefit to my search campaigns beyond just clicks and post-click activity. Does anyone know of any studies that have been conducted where clicks or revenue have been attributed to search impressions? I'm looking for percentages or metrics which I can apply to my existing numbers. Many thanks in advance for any assitance.

pl