Answering these makes marketing more efficient by improving targeting and by identifying and eliminating the famed half of the marketing budget that is wasted. To address these questions, marketers have trained their big-data telescopes at a single point: predicting each customer’s next transaction. In pursuit of this prize marketers strive to paint an ever more detailed portrait of each consumer, memorizing her media preferences, scrutinizing her shopping habits, and cataloging her interests, aspirations and desires. The result is a detailed, high-resolution close-up of each customer that reveals her next move.