If the Lone Star State were its own country, it would have the 12th-highest GDP in the world. Certainly, a fragment of that growth is without a doubt attributed to Texas’ bustling energy businesses.  However, the state also boasts a thriving start-up network and research system.

Notably, over the past 20 years, Texas has become an increasingly important part of the US economy. In 1995, it made up 6.5% of the total US GDP; by 2014 it was over 9%.  Undeniably, an important segment of Texas’ thriving economy is the academia the state produces.

In fact, four public Universities in Texas earned a coveted ranking this month, breaking into the top tier of research universities nationally. Texas Tech, the University of North Texas and the University of Texas campuses at Arlington and Dallas were added to The Carnegie Classification of Institutions of Higher Education list of schools with the “Highest Research Activity” — a major achievement after years of additional state funding flowed into the schools seeking to reach the top tier.

The Carnegie Classification’s assignment to categories of highest, higher and moderate research activity is based on the following correlates: research and development expenditures in both science and engineering and in non-science and engineering fields; science and engineering research staff including post-doctoral candidates and non-faculty staff with doctorates; and doctoral conferrals in humanities and social sciences fields, in STEM fields, and in other areas such as business, education, public policy and social work.