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            【题 名】：  “Econometric Methods for Fractional
Response Variables with an Application to 401(k) Plan Participation Rates.”
            【作 者】： Papke, Leslie E. and Jeffrey M. Wooldridge.
            【期刊、会议、单位名称】：Journal of
Applied Econometrics 11(6):619–632.
            【年, 卷(期), 起止页码】：Journal of
Applied Econometrics 11(6):619–632.
            【全文链接】：http://ideas.repec.org/p/nbr/nberte/0147.html
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