Conducting a group buying advertising campaign. Receiving a specification for a group-buying offer. Creating a candidate ad campaign based on the received specification. The candidate ad campaign includes at least one campaign feature. The candidate ad is characterized by at least one generalized feature. Determining the expected effectiveness of the candidate ad campaign. For an expected effectiveness less than the aggregate effectiveness of a set of at least one previously run ad campaigns having a generalized feature in common with the candidate campaign, editing the candidate ad campaign to incorporate at least one feature of the set of at least one previously run ad campaigns. Running the edited ad campaign in an ad display network. Collecting effectiveness data for each run ad campaign.