Every time a visitor is shown or clicking one of the products in the recommendation block, the event is tracked by engage. All the events are then on frequent basis processed and aggregated into statistics showing the performance of the recommendations. 

The "Indirect Attributable Revenue" is calculated based on the criteria that a visitor/customers has clicked one or multiple recommendations and have within the time period of 7 days placed an order. The full order value is used for the calculations.

This metric is a good measure of the interaction between the visitor/customer and engage, and gives the store owner actual data on the navigation assistance provided.