- We compare the seller's expected revenue in asymmetric second-price auctions with the benchmark case where all bidders have the average distribution. We show that with two bidders, asymmetry has a negative effect on revenue. However, for n>2 bidders there is no clear observation we can make. We prove that in the case of weak asymmetry, sellers prefer asymmetry over low valuations and symmetry over high valuations. In addition, we show that a good approximation for the expected revenue in the case of weak asymmetry can be obtained by calculating the revenue of the symmetric auction with identical distributions equal to the geometric or arithmetic average.