Chen, Shiu-ShengShiu-ShengChenSHIU-SHENG CHENEngel, CharlesCharlesEngel2018-09-102018-09-102005http://www.scopus.com/inward/record.url?eid=2-s2.0-15844420471&partnerID=MN8TOARShttp://scholars.lib.ntu.edu.tw/handle/123456789/318292391126 bytesapplication/pdf[SDGs]SDG8Does 'aggregation bias' explain the PPP puzzle?journal article10.1111/j.1468-0106.2005.00260.x