He got his phd from UW, just not that UW. It's in the wiki page also. University of Washington is one of the best state schools in the world, and routinely ranks in the top ten with its computer science department.
I find Americans view "America" as "The World". I'm not questioning your metrics, your statistics, or the quality of UWashington, but I think you mean 'Public School'.
The phrase state school is meaningless if you live in countries that don't have states.
