The cost per sale is the commission earned by the affiliate on every sale completed by a user that came from that affiliate Web site on to the merchant's Web site.
The average advertising cost per online sale.
The cost of placing an ad on a site based on how many sales result from the ad.
When purchasing advertising, the price per sale generated. The visitor's behavior is typically tracked with a cookie that is activated by clicking on the ad and then read on the advertiser's site after the sale is completed.