Just look at his bio:

Current Positions
Visiting Scholar, New York University's Wagner School

Past Positions
Director, The Hamilton Project; Nonresident Senior Fellow, Center on Budget and Policy Priorities; Special Assistant to the President for Economic Policy (1999-2000); Staff Economist, Council of Economic Advisors (1996-1997); Senior Economic Advisor to the Chief Economist, The World Bank (1997-1998)

(admittedly he probably wrote that himself)

Walmart has excellent technical skills, which I admire, even if I loathe their people skills.