Systems and methods for pricing portfolio allocations of ad deliveries to a plurality of online ads are disclosed. A first set of values is determined, each value of the first set of values representing for an online ad of the plurality of online ads, a bid an advertiser has associated with the online ad. A second set of values is determined, the second set of values representing statistics on variability of payoffs from showing ads. A risk value associated with the publisher is determined. Using a portfolio allocation algorithm, a set of ad delivery allocations associated with the plurality of online ads is determined, and, using a Vickrey-Clarke-Groves mechanism, a set of prices associated with the plurality of online ads is determined, both of which are determined based on the first set of values, the second set of values, and the risk value.