Persuasive Puffery.

Sellers often make claims about product strengths without providing evidence. Even though such claims are mere puffery, we show that they can be credible because talking up any one strength comes at the implicit trade-off of not talking up another potential strength. Puffery pulls in some buyers who value product attributes that are talked up or emphasized while pushing away other buyers who infer that the attributes they value are relative weaknesses. When the initial probability of making a sale is low, there are more potential buyers to pull in than to push away, so puffery is persuasive overall. This persuasiveness requires that buyers have some privacy about their preferences so that the seller does not completely pander to them. More generally, the results show how comparative cheap talk by an expert to a decision maker can be credible and persuasive in standard discrete choice models used throughout marketing, economics, and other disciplines.