Sponsored search mechanisms, where advertisers bid for placement to beas close to the top in the listing of search results, are the fastestgrowing among online search models. Sponsored search in popular searchservices such as Google and Yahoo! employ an auction mechanism whereinfirms can bid,...

Online sponsored search advertising has emerged as the dominant online advertising format largely due to their "pay-for-performance" nature, wherein advertising expenditures are closely tied to outcomes. While the pay-for-performance format substantially reduces the "wastage" incurred by...

Sponsored search mechanisms, where advertisers bid for placement to be as close to the top in the listing of search results, are the fastest growing among online search models. Sponsored search in popular search services such as Google and Yahoo! employ an auction mechanism wherein firms can...