STOCKHOLM — The Nobel memorial prize in economics has been awarded to Daron Acemoglu, Simon Johnson and James A. Robinson for research into differences in prosperity between nations.

The announcement was made today in Stockholm.

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

The award is formally known as the Bank of Sweden Prize in Economic Sciences in Memory of Alfred Nobel. The central bank established it as a memorial to Nobel, the 19th-century Swedish businessman and chemist who invented dynamite and established the five Nobel Prizes. The first winners were Ragnar Frisch and Jan Tinbergen in 1969.

Last year, Harvard University professor Claudia Goldin was honored for her research that helps explain why women around the world are less likely than men to work and why they earn less money when they do. She was only the third woman among the 93 economics laureates.

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 Nobel’s death in 1896.