The first paragraph says it all: AETNA wants to attract and retain workers. That’s what efficiency wages are all about.
Aetna to Boost Incomes of Lowest-Paid Workers (WSJ)
There is also more to say about efficiency wages. The theory of efficiency wages, if applied to macro can only explain rising wages. It’s not a theory that can explain all wages holding at levels above VMP, unless the model includes heterogeneous wages.
The Columbus Dispatch makes some additional points:
Aetna’s $16 wage a bid to attract, keep talent
HuffPost takes things to another level:
Aetna CEO Asked Execs To Read Piketty, Then Gave His Lowest-Paid Workers A Raise
To the CEO of Aetna: Three More Ideas to Reduce Inequality
There are many more articles, too—just do a Google search on the title.