Response to Chemin and to Pitt
回应Chemin和Pitt对Duvendack和Palmer-Jones论文的批评,指出Chemin的假设不现实且变量构建不透明,Pitt的倾向得分匹配结果有误导性,坚持原结论:Pitt和Khandker的研究设计薄弱,无法用复杂方法弥补。
Abstract We reply to the discussion and criticisms of Matthieu Chemin (MC) and Mark Pitt (MP) to our paper ((Duvendack and Palmer-Jones (DPJ)) (all this issue). MC clarifies many issues which now make replication pure probable (but not yet achieved), and MP identifies a number of problems with DPJ (some of which are shared with Chemin, 2008). Chemin (2008) made at least one crucial undocumented and unrealistic assumption, and did not document many of his variable constructions. MP correctly identifies inappropriate members of control groups, and other problems, but his claim that his propensity score matching (PSM) results provide support for Pitt and Khandker's (1998 – PnK) most important claim is misleading as it is not robust. We see no reason to change our conclusion that PnK is limited as an evaluation of microfinance by a weak research design which cannot be convincingly mitigated by the sophisticated methods used in PnK, or by PSM.