Seller satisfaction will be the highest if the user buys the item. Basing the recommender on sales will make it a seller-focused recommender. If the recommende

Seller satisfaction will be the highest if the user buys the item. Basing the recommender on sales will make it a seller-focused recommender. If the recommender somehow can be based on buyer satisfaction - it would be a system that focuses on the buyer. It would then perhaps not please the seller. Taking it one step further, if a buyer is VERY satisfied, the buyer is likely to return for MORE purchases, ensuring the satisfaction of BOTH seller and buyer with the first recommendation. This is the ultimate recommender, measuring not first-purchase buyer/seller satisfaction, but rather measuring "so satisfied with the first purchase that the buyer returned for a second purchase".