Google has a multiscreen ad plan. A study conducted at CBS's Television City media lab run by Nielsen measures the incremental impact of multiscreen advertising. across TV, PCs, smartphones and tablets. A 15-second video ad promoting Volvo's S60 sedan was shown to different groups of participants. Some people saw no ads, while others the ad on a different combinations of screens controlling for frequency. Johanna Werther and Ben Chung explain the results and the impact to viewers on product recall.