A study funded by AdSpace and Macy’s compared results at a Macy’s store outfitted with CoolSign ads with those at the chain’s other outlets. Sales of cosmetics nearly doubled when customers were prodded with live-action commercials as opposed to conventional cardboard posters. Swimsuit sales more than doubled, and sales of lingerie quadrupled. Another study, by the research firm Arbitron, found that digital displays outperformed bus signs by 38 percent in ad recall, and beat billboards by 16 percent.