document: How much is your personal recommendation worth ? Suppose you buy a new laptop and , simply because you like it so much , you recommend it to friends , encouraging them to purchase it as well . What would be an adequate price for the vendor of the laptop to pay for your recommendation ? Personal recommendations like this are of considerable commercial interest , but unlike in sponsored search auctions there can be no truthful prices . Despite this `` lack of truthfulness '' the vendor of the product might still decide to pay you for recommendation e.g. because she wants to ( i ) provide you with an additional incentive to actually recommend her or to ( ii ) increase your satisfaction and\/or brand loyalty . This leads us to investigate a pricing scheme based on the Shapley value ( 5 ) that satisfies certain `` axioms of fairness '' . We find that it is vulnerable to manipulations and show how to overcome these difficulties using the anonymity-proof Shapley value of ( 4 ) .
doc_bio_tags: O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O