Research on the Effects of the U.S. Welfare System on the Low Income Population

关于福利对生育、婚姻、同居和家庭影响的大量实证文献 在过去的十年里，总体结构有所发展。这种文学的主要倾向是 这表明福利在许多人假设的方向上有一些影响（例如，提高福利 导致结婚率下降和非婚生育率上升的好处），但有相当大的 不确定性的影响的大小，甚至可能存在，因为大 不同研究中估计值的离散度。研究结果缺乏共识， 研究对决策者的影响，他们往往认为学术研究是不确定的， 或者，作为能够支持任何结论。该项目将通过开展一项 一系列的复制，鲁棒性和协调研究，试图缩小过去的差异， 研究工作，并试图建立一个共识的存在和规模的影响。该项目将 分为主要阶段，解释研究之间的差异，以及次要阶段， 使用统计规格测试和新规格测试来选择“最佳”模型。在各大 在初级阶段，几项主要研究的估计值将首先使用相同的数据集进行复制， 模型，以及这些论文中使用的估计技术;那么估计的稳健性将是 通过在其他论文中使用的数据集上估计每篇论文中使用的模型， 尽可能使用相同的样本、变量定义和计量经济学方法; 研究之间的差异将被追溯到这些因素中的每一个的差异--基础因素的差异 相同变量的数据集;变量定义;二次抽样人群;模型规格 经济计量方法。第二阶段将包括规格测试， 替代模型规格以及更详细的检查涉及的几个假设， 家庭背景的重要性，男女工资的影响，以及替代统计 规范.

A substantial empirical literature on the effect of welfare benefits on fertility, marriage, cohabitation, and family structure in general has grown up over the last decade. The central tendency of this literature tends to suggest that welfare benefits have some effect in the direction many have hypothesized (e.g., higher welfare benefits leading to lesser marriage rates and greater nonmarital fertility rates) but there is considerable uncertainty surrounding the magnitude of the effect, and possibly even its existence, because of the large dispersion in estimates across different studies. This lack of consensus in research findings has weakened the impact of the research on policy-makers, who often regard the academic research as inconclusive or, alternatively, as capable of supporting any conclusion. This project will address this problem by conducting a series of replication, robustness, and reconciliation studies in an attempt to narrow the differences across past research efforts and in an attempt to build a consensus for the existence and size of effects. The project will be divided into a primary phase in which differences across studies are explained and a secondary phase in which "best" models are chosen using statistical specification tests and new specifications tested. In the major and primary phase, the estimates from several major studies will first be replicated using the same data sets, models, and estimating techniques used in those papers; then the robustness of the estimates will be ascertained by estimating the models used in each paper on the data sets used in the other papers, using to the greatest extent possible the same samples, variable definitions, and econometric methods; then the differences between studies will be traced to differences in each of these factors-differences in the underlying data sets for the same variables; in variable definition; in subsampled populations; and in model specification and econometric method. The secondary phase will consist of specification tests to choose among the alternative model specifications as well as a more detailed examination of several hypotheses involving the imporance of family background, the influence of male and female wages, and alternative statistical specifications.