Cost Per Incremental Action: Efficient Pricing of Advertising

Advertisers seek to maximize profits by investing in advertising. We propose a “cost-per-incremental-action” (CPIA) pricing model which incorporates the causal contribution of advertising in order to achieve the advertisers' objectives such as profit maximization. CPIA pricing aligns marketplace incentives among all participants to help advertisers achieve their objectives via ad effectiveness and, by doing so, eliminates the adverse behaviors resulting from the misaligned incentives of commonly used pricing models. CPIA pricing can be implemented by adapting cost-per-action (CPA) bidding by either the ad platform or advertiser's bidding agent. We discuss CPIA pricing in the context of several examples, including recent empirical studies measuring the causal effects of advertising within the context of existing pricing models.