|
Brookings Institution (United States)
8
|
Center for Education Policy Research (United States)
2
|
National Bureau of Economic Research (United States)
2
|
|
Science Policy Research Unit (United Kingdom)
2
|
American Enterprise Institute (United States)
1
|
Center for Development Research (Germany)
1
|
|
Center for Strategic and International Studies (United States)
1
|
International Institute for Applied Systems Analysis (Austria)
1
|
International Institute for Environment and Development (United Kingdom)
1
|
|
Mathematica Policy Research (United States)
1
|
