There are many variables, crossovers, and subloops. Of course, all other things are rarely equal. Regional preferences can overcome reputation. Thus Virginia may draw more from Texas than from Northwestern. Even in a single geographic area, preferences can overcome reputation.
Cost can overcome reputation.
This makes the food chain particularly convoluted in states with good, low-cost public schools. Illinois may draw from Northwestern, Berkeley may draw from Stanford, and UNC may draw from Duke among the state residents accepted at these schools. The same is true of geographically isolated state schools, such as North and South Dakota, Wyoming, and Hawaii. Based on those hypotheses, I have created a picture of the entire wait list food chain. The schematic is entirely the result of my own ratiocination.