AP Paul Romer, co-winer of the 2018 Nobel Prize for economics, has studied the way innovation drives prosperity and has looked at ways to encourage it.

Former Colorado Gov. Roy Romer thought history had passed over his son, Paul, an economics professor at New York University. Paul Romer's research into the role of technology in economic growth had put him on the shortlist for the Nobel Prize in economics.

But year after year, Roy Romer said, the call never came.

Until Monday.

"I knew he had that talent all along," Roy Romer said of Paul, hours after he learned his son had won this year's Nobel Prize in economics. "I was pleased about his career without this. I'm pleased with it."

Paul Romer will share the 2018 prize with William Nordhaus, a professor at Yale. The Nobel Prize committee said Romer and Nordhaus have created ways to address, "some of our time's most basic and pressing questions about how we create long-term sustained and sustainable economic growth."

“The message is that it’s needed for countries to cooperate globally to solve some of these big questions,” Goran K. Hansson, secretary general of the Royal Swedish Academy of Sciences, told the New York Times.

Roy Romer was governor of Colorado from 1987 to 1999. He and his wife Bea raised seven children; notably, his son Chris was a state Senator and candidate for Denver mayor in 2011. He takes their achievements in stride.

"I think they are all equal in their performance," he said. "Some get recognition, some don't. That's not how I judge a life."