Consumer information on products affects competition and profits. We analyze firms' decisions to impart product information through advertising: comparative advertising also allows them to impart information about rivals' products. If firms sell products of similar qualities, both want to...

Improved consumer information about (symmetric) products can lead to better matching but also higher prices, so consumer surplus can go up or down, while profits rise. With enough firm asymmetry though, the stronger firm's price falls with more information, so both effects benefit consumers....

Advertising messages compete for scarce attention. “Junk” mail, “spam” e-mail, and telemarketing calls need both parties to exert effort to generate transactions. Message recipients supply attention depending on average message benefit, while senders are motivated by profits. Costlier...