The Nobel memorial prize in economics was awarded Monday to three economists who have studied why some countries are rich and others poor and have documented that freer, open societies are more likely to prosper.

The work by Daron Acemoglu, Simon Johnson and James A. Robinson B次元官网网址渄emonstrated the importance of societal institutions for a countryB次元官网网址檚 prosperity,B次元官网网址� the Nobel committee of the Royal Swedish Academy of Sciences said at the announcement in Stockholm.

Acemoglu and Johnson work at the Massachusetts Institute of Technology, while Robinson does his research at the University of Chicago.

Jakob Svensson, chair of the Committee for the Prize in Economic Sciences, said their analysis has provided B次元官网网址渁 much deeper understanding of the root causes of why countries fail or succeed.B次元官网网址�

Reached by the academy in Athens, Greece, where he was to speak at a conference, the Turkish-born Acemoglu, 57, said he was astonished by the award.

B次元官网网址淵ou never expect something like this,B次元官网网址� he said.

Acemoglu said the research honored by the prize underscores the value of democratic institutions.

B次元官网网址淚 think broadly speaking the work that we have done favors democracy,B次元官网网址� he said in a telephone call with the Nobel committee and reporters in Stockholm.

But, he added: B次元官网网址淒emocracy is not a panacea. Introducing democracy is very hard. When you introduce elections, that sometimes creates conflict.B次元官网网址�

In an interview with The Associated Press, Robinson, 64, said he doubts that China can sustain its economic prosperity as long as it keeps a repressive political system.

B次元官网网址淭hereB次元官网网址檚 many examples in world history of societies like that that do well for 40, 50 years,B次元官网网址� Robinson said by phone. B次元官网网址淲hat you see is thatB次元官网网址檚 never sustainable. B次元官网网址� The Soviet Union did well for 50 or 60 years.B次元官网网址�

Robinson said many societies have successfully made the transition to what he, Acemoglu and Johnson call an B次元官网网址渋nclusive society.B次元官网网址�

B次元官网网址淟ook at the United States,B次元官网网址� Robinson said. B次元官网网址淭his was a country of slavery, of privilege, where women were not allowed to take part in the economy or vote.B次元官网网址�

B次元官网网址淓very country that is currently relatively inclusive and open made that transition,B次元官网网址� he added. B次元官网网址淚n the modern world, youB次元官网网址檝e seen that in South Korea, in Taiwan, in Mauritius.B次元官网网址�

Acemoglu and Robinson wrote the 2012 bestseller, B次元官网网址淲hy Nations Fail: The Origins of Power, Prosperity, and Poverty,B次元官网网址� which argued that manmade problems were responsible for keeping countries poor.

In their work, the winners looked, for instance, at the city of Nogales, which straddles the U.S.-Mexico border.

Despite sharing the same geography, climate and a common culture, life is very different on either side of the border. In Nogales, Arizona, to the north, residents are relatively well-off and live long lives most children graduate from high school. To the south, in MexicoB次元官网网址檚 Nogales, Sonora, residents are much poorer, and organized crime and corruption abound.

The difference, the economists found, is a U.S. system that protects property rights and gives citizens a say in their government.

Acemoglu expressed worry Monday that democratic institutions in the United States and Europe were losing support from the population.

B次元官网网址淪upport for democracy is at an all-time low, especially in the U.S., but also in Greece and in the UK and France,B次元官网网址� Acemoglu said on the sidelines of the conference in an Athens suburb.

B次元官网网址淎nd I think that is a symbol of how people are disappointed with democracy,B次元官网网址� he said. B次元官网网址淭hey think democracy hasnB次元官网网址檛 delivered what it promised.B次元官网网址�

Robinson agreed. B次元官网网址淐learly, you had an attack on inclusive institutions in this country,B次元官网网址� he said. B次元官网网址淵ou had a presidential candidate who denied that he lost the last election. So President (Donald) Trump rejected the democratic rule of the citizens. B次元官网网址� Of course, IB次元官网网址檓 worried. IB次元官网网址檓 a concerned citizen.B次元官网网址�

Johnson told the AP that economic pressures were alienating many Americans.

B次元官网网址淎 lot of people who were previously in the middle class were hit very hard by the combination of globalization, automation, the decline of trade unions, and a sort of shift more broadly in corporate philosophy,B次元官网网址� Johnson said. B次元官网网址淪o instead of workers being a resource to be developed, which they were in the 19th and early 20th century, they became a cost to be minimized B次元官网网址� Now, that squeezed the middle class.B次元官网网址�

B次元官网网址淲e have, as a country, failed to deliver in recent decades on what we were previously very good at, which was sharing prosperity,B次元官网网址� Johnson said.

One key for the future, Johnson said, is how societies manage new technologies such as artificial intelligence.

B次元官网网址淎I could go either way,B次元官网网址� he said. B次元官网网址淎I could either empower people with a lot of education, make them more highly skilled, enable them to do more tasks and get more pay. Or it could be another massive wave of automation that pushes the remnants of the middle down to the bottom. And then, yes, youB次元官网网址檙e not going to like the political outcomes.B次元官网网址�

In their work, the economists studied institutions that European powers such as Britain and Spain put in place when they colonized much of the world starting in the 1600s. They brought different policies to different places, giving later researchers a B次元官网网址渘atural experimentB次元官网网址� to analyze.

Colonies that were sparsely populated offered less resistance to foreign rule and therefore attracted more settlers. In those places, colonial governments tended to establish more inclusive economic institutions that B次元官网网址渋ncentivized settlers to work hard and invest in their new homeland. In turn, this led to demands for political rights that gave them a share of profits,B次元官网网址� the Nobel committee said.

In more densely populated places that attracted fewer settlers, the colonial regimes limited political rights and set up institutions that focused on B次元官网网址渂enefiting a local elite at the expense of the wider population,B次元官网网址� it said.

B次元官网网址淧aradoxically, this means that the parts of the colonized world that were relatively the most prosperous around 500 years ago are now those that are relatively poor,B次元官网网址� it added, noting that IndiaB次元官网网址檚 industrial production exceeded the American coloniesB次元官网网址� in the 18th century.

The economics prize is formally known as the Bank of Sweden Prize in Economic Sciences in Memory of Alfred Nobel. The central bank established it in 1968 as a memorial to Nobel, the 19th-century Swedish businessman and chemist who invented dynamite and established the five Nobel Prizes.

Though Nobel purists stress that the economics prize is technically not a Nobel Prize, it is always presented together with the others on Dec. 10, the anniversary of NobelB次元官网网址檚 death in 1896.

Nobel honors were announced last week in medicine, physics, chemistry, literature and peace.