It's Mountain West vs. Pac-12 SAN JOSE, Calif. - In the Mountain and Pacific time zones, the rise of the Mountain West Conference has turned it into the chief rival of the Pac-12 Conference In men's basketball, which conference is better? If the computers and the crunched numbers are to be believed, the Mountain West is one of the best conferences in the country, and perhaps the best. The Pac-12 is muddled somewhere in the middle, an upper-tier conference with mid-tier basketball. Both have something to prove. The Pac-12 wants to show it is underrated. The Mountain West wants to show it is not overrated. Each conference placed five teams in the tournament. In one case, they will go head-to-head, fifth-seeded Nevada-Las Vegas against No. 12 California here at HP Pavilion. The Mountain West is credited with parity. The Pac-12 is chided for mediocrity. At least one national pundit predicted the Pac-12 will go 0-5. Yet the five Pac-12 teams in the tournament finished 8-3 against the Mountain West this season. The five Mountain West tournament teams were 5-4 against the Pac-12. Oregon, the Pac-12 runner-up and conference-tournament champion, ranked in the top 25 until the final week of the regular season, ended up seeded 12th. "It's an inexact science," Oregon Coach Dana Altman said, diplomatically. His Ducks play No. 5 Oklahoma State. No Pac-12 team is seeded higher than sixth (U.C.L.A. and Arizona). Colorado received a No. 10 seed, and Cal a No. For those who believe betting lines, only Arizona, playing No. 11 Belmont, is a favorite to win on Thursday and Friday. The Mountain West is led by third-seeded New Mexico. U.N.L.V. and San Diego State (seeded seventh) are favored to join the Lobos in the next round. Colorado State (eighth) is a slight underdog to Missouri. Boise State, seeded 13th, lost a first-round First Four game against LaSalle on Wednesday night. The computers, the pundits, even the odds makers believe the Mountain West is better. What will the N.C.A.A.tournament say?