Attribution is critical for digital marketers. Attribution is also very difficult. Maybe a coupon code email was the final nudge that pushed a consumer to a purchase, but what about the pre-roll ads, the tweets, and the numerous times she read customer reviews? Every journey to a purchase involves multiple experiences. So what is the process for determining who gets credit? The good news is, according to Google, if you're struggling with attribution, you're not alone. Google's global analytics lead, Rachel Witalec, says, "Very few people are doing attribution well, and very few know how." B...