NCAA DI softball selection process(and VB and baseball and soccer and a few other sports):
1. Select the top 16 seeds and give them the option to host a regional.
2. Sort everybody else purely by geography.
3. Try to make sure you don't have 3 top teams or 3 bottom feeders in the same regional(but don't try too hard).
4. Rank each regional 1-4.
Draw a 350mi circle around Minneapolis. Assuming the Gophers stay in the top 16, and the Bison win the Summit tourney, you can be certain the other two teams will come from within that circle if possible. UNI will go to MSP if they make it. Other possibilities would be Drake, UWGB, etc. I don't think they put teams from the same conference in the same regional if they can avoid it, so Iowa and Wisc are out.
2009: Minnesota unseeded
(7)Oklahoma, Tulsa, Arkansas, NDSU
2010: Minnesota unseeded
(3)Washington, Nebraska, North Carolina, NDSU
2011: Minnesota unseeded
(1)Arizona St, San Diego St, Long Beach St, NDSU
2012: Minnesota unseeded
(13)Arizona, Hawai'i, Notre Dame, NDSU
2014: Minnesota seeded
(16)Minnesota, NDSU, Auburn, Green Bay
2015: Minnesota seeded
(?)Minnesota, NDSU, ???, ???