Nobel prize for economics awarded to two Americans

Americans Thomas Sargent and Christopher Sims have won the 2011 Nobel economics prize.

The Royal Swedish Academy of Sciences cited "their empirical research on cause and effect in the macroeconomy".

Peter Diamond, Dale Mortensen and Christopher Pissarides won the 2010 prize for their work on how regulation and policy affects jobs and wages.

The award's official name is the Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel.

By BBC News