In Google Analytics, you want to find out which channels—direct, organic search, referral, email, paid search, other advertising, social, and display—account for your sales. Here are seven common attribution models: Last interaction model: The last channel that the customer interacted with before buying receives 100% of the credit for the conversion. Last nondirect click model: All direct traffic is ignored in this model, which credits 100% of the conversion to whatever interaction the customer had before making a purchase. Last AdWords click model: The last AdWords ad that the customer interacted with before buying receives 100% of the credit for the conversion. First interaction model: The first channel that the customer interacted with before buying receives 100% of the credit for the conversion. Linear model: Every channel that the customer interacted with before converting receives an equal share of the conversion credit. Time decay model: This one gives most of the credit to the channels the customer interacted with in the time nearest to the sale. Position-based model: This model attributes 40% of the conversion credit to the first interaction, 40% to the last interaction, and the remaining 20% equally across any interactions that occurred between the first and last interactions.