世行LUC CHRISTIAENSEN与日本东京大学YASUYUKI TODO的合作研究，Poverty Reduction During the Rural–Urban Transformation – The Role of the Missing Middle，对中国城镇化发展研究有重要借鉴意义。


摘要：

    As countries develop, they restructure away from agriculture and urbanize. But structural transformation and urbanization
patterns differ substantially, with some countries fostering migration out of agriculture into rural off farm activities and secondary
towns, and others undergoing rapid agglomeration in mega cities. Using cross-country panel data for developing countries spanning 1980–2004, it is found that migration out of agriculture into the missing middle (rural nonfarm economy and secondary towns) yields more inclusive growth patterns and faster poverty reduction than agglomeration in mega cities. This suggests that patterns of urbanization deserve much more attention when striving for faster poverty reduction.