Content providers value attention: this requires not only being seen but also being thought of as worthy of consideration. Social media and other platforms affect these outcomes and charge for them. Providers on the platform come in two types. Consumers value good ones but not "bots." A platform can distinguish bots from good providers but cannot tell how much a good provider values attention. The platform offers combinations of price, certificate, and number of views; these offerings appeal differently to different providers. Steering and certification interact. In particular, the combination allows for higher consumer surplus (and platform profits) than steering alone; consumers gain from increased content diversity. In addition, a model of attention allows for the analysis of welfare, and comparative statics point to when platforms might choose imperfect certification.
