The photos of the winners of the 2019 Nobel Prize in Economics are seen at the Royal Swedish Academy of Sciences, Stockholm, Sweden, Oct. 14, 2019. The 2019 Nobel Prize in Economics has been awarded to Abhijit Banerjee, Esther Duflo and Michael Kremer "for their experimental approach to alleviating global poverty," the Royal Swedish Academy of Sciences announced Monday. (Photos: Xinhua)

Photo taken on Oct. 14, 2019 shows the announcement of the winners of the 2019 Nobel Prize in Economics at the Royal Swedish Academy of Sciences, Stockholm, Sweden. The 2019 Nobel Prize in Economics has been awarded to Abhijit Banerjee, Esther Duflo and Michael Kremer "for their experimental approach to alleviating global poverty," the Royal Swedish Academy of Sciences announced Monday.

Jakob Svensson (R), member of the Committee for the Prize in Economic Sciences in Memory of Alfred Nobel, speaks on the contributions of the winners of the 2019 Nobel Prize in Economics at the Royal Swedish Academy of Sciences, Stockholm, Sweden, Oct. 14, 2019. The 2019 Nobel Prize in Economics has been awarded to Abhijit Banerjee, Esther Duflo and Michael Kremer "for their experimental approach to alleviating global poverty," the Royal Swedish Academy of Sciences announced Monday.

The photos of the winners of the 2019 Nobel Prize in Economics are seen at the Royal Swedish Academy of Sciences, Stockholm, Sweden, Oct. 14, 2019. The 2019 Nobel Prize in Economics has been awarded to Abhijit Banerjee, Esther Duflo and Michael Kremer "for their experimental approach to alleviating global poverty," the Royal Swedish Academy of Sciences announced Monday.

Photo taken on Oct. 14, 2019 shows the announcement of the winners of the 2019 Nobel Prize in Economics at the Royal Swedish Academy of Sciences, Stockholm, Sweden. The 2019 Nobel Prize in Economics has been awarded to Abhijit Banerjee, Esther Duflo and Michael Kremer "for their experimental approach to alleviating global poverty," the Royal Swedish Academy of Sciences announced Monday.

Jakob Svensson (R), member of the Committee for the Prize in Economic Sciences in Memory of Alfred Nobel, speaks on the contributions of the winners of the 2019 Nobel Prize in Economics at the Royal Swedish Academy of Sciences, Stockholm, Sweden, Oct. 14, 2019. The 2019 Nobel Prize in Economics has been awarded to Abhijit Banerjee, Esther Duflo and Michael Kremer "for their experimental approach to alleviating global poverty," the Royal Swedish Academy of Sciences announced Monday.