This is a preview. Log in through your library . Abstract The system GMM estimator for dynamic panel data models combines moment conditions for the model in first ...

A behind-the-scenes blog about research methods at Pew Research Center. For our latest findings, visit pewresearch.org. Identifying causal relationships from observational data is not easy. Still, ...

Environment and Development Economics, Vol. 8, No. 4 (October 2003), pp. 581-601 (21 pages) The purpose of this study is to test empirically the hypothesis of the inverted U-shaped relationship ...