For the second straight year, a private university specializing in aviation and aerospace has claimed the top spot in the U.S. News and World Report list of online bachelor’s degree programs.

Just behind Embry-Riddle Aeronautical University – Worldwide in the rankings released Tuesday are several large public universities seeking to use technology to expand their market profile.

Temple University, the University of Oklahoma, Arizona State University and Western Kentucky University, in that order, round out the top five in the latest U.S. News analysis.

Temple and Arizona State also fared well on another U.S. News ranking: Temple, which is in Philadelphia, ranked first for the third straight year in the magazine’s analysis of online programs for master’s degrees in business administration. Arizona State ranked fifth, tied with the University of Florida.

“Online learning is relatively new but growing in popularity because of the flexibility it offers,” Anita Narayan, managing editor of education at U.S. News, said in a statement. “We developed the Best Online Programs rankings to provide students with the tools to identify programs that offer top faculty, positive student engagement and generous support services — all of which are key to productive online learning.”

The online market for higher education is large and fluid. It encompasses degree programs at public, private and for-profit schools as well as what are known as massive open online courses, or MOOCs, that students can take for free without earning credit.

Consumers often turn to lists to navigate such complicated markets. But exactly how to rank online programs is a matter of debate. Online students run the gamut from those who are young and taking college courses for the first time, to working adults who might have some credits or relevant professional experience and are seeking to complete a degree. Some online programs mix in a few in-person sessions, and some don’t. Federal data on graduation rates tends to focus on first-time students, not those who are returning to school.

One of the largest online schools, the public University of Maryland University College, said in 2016 that it does not participate in the U.S. News online rankings because it disagrees with the magazine’s methodology.

U.S. News said it ranked 311 online bachelor’s programs, using factors such as graduation and retention rates, class size, faculty credentials, participation in best practices, student debt and scores on reputational surveys. Here are this year’s top 20.

1. Embry-Riddle
2. Temple
3. Oklahoma
4. Arizona State
5. Western Kentucky
6. California University of Pennsylvania
6. West Texas A&M University
8. California Baptist University
8. New England Institute of Technology
8. Ohio State University at Columbus
8. Oregon State University
8. Pennsylvania State University — World Campus
8. University of Illinois at Chicago
14. Utah State University
15. Colorado State University — Global Campus
15. Daytona State College
15. Fort Hays State University
15. Savannah College of Art and Design
20. University of Florida

Here are what U.S. News considers the top 20 online MBA programs among 255 analyzed:

1. Temple
2. Carnegie Mellon University
3. Indiana University at Bloomington
4. University of North Carolina at Chapel Hill
5. Arizona State
5. University of Florida
7. University of Texas at Dallas
8. Penn State World Campus
9. University of Maryland at College Park
10. Arkansas State at Jonesboro
10. Auburn University
12. Ball State University
12. University of Massachusetts at Amherst
12. University of Southern California
12. University of Wisconsin MBA Consortium
16. Florida State University
16. University of Wisconsin at Whitewater
18. Mississippi State University
18. North Carolina State University
18. University of South Florida — St. Petersburg

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