SHOP TALK: Cross-Channel Sales and Budget for Multichannel Retailers

The most important things to execute are mail/holdout tests within direct mail and email marketing. Take email marketing, for instance. For the next three months, take 5 percent of your email marketing file and don't send one single email campaign to that audience. Randomly choose another 5 percent of your email file and mail them as you normally would. At the end of the three months, compare demand generated in all of your marketing channels across the two segments.