Which university in the United States is better to study for a master's or doctor's degree in tourism?

The tourism departments of four typical universities in the United States, namely Purdue University, University of Nevada, University of Las Vegas, University of Texas and University of Illinois, focus on hotel industry, tourism industry and catering industry, with emphasis on service management. The latter mainly focuses on tourism resources and scenic spots, and the research focuses more on the positioning of development and protection. It is better to study tourism in America or go to these four universities.