Abstract: Embodiments are directed to modeling physical material flow relationships between injector wells and producer wells in a reservoir and to quantifying a level of uncertainty in a connection-based model. In one scenario, a computer system calculates pressure distribution within the reservoir using sensor data. Next, the computer system applies the calculated pressure distribution as an input to a tracer algorithm for an injector well and for a producer well to identify tracer flow values for materials flowing from the injector well to the producer well. The computer system further combines the identified tracer flow values to generate well allocation factors representing relationships in material flow.