Topics on Inequality: The Changing Household Composition and Implications for Policy Coordination

该项目由两个部分组成，涉及人与人之间和国家之间不平等的决定因素和影响。第一部分研究了最近美国家庭构成的巨大变化。从70年代中期到90年代初，美国未婚女性的比例急剧上升（在30至44岁年龄组中从17%上升到30%）。与此同时，人们的婚姻生活也越来越少。非婚生子女的抚养比例稳步上升，单身母亲占女性总人口的比例从12%上升到17%，而同期的总生育率保持不变。在同一时期还有另一个重大变化：现在的工资结构与25年前大不相同。平均工资有了适度的增长。与此同时，受过大学教育的人与没有受过大学教育的人的工资比例以及女性与男性的工资比例也出现了相当大的增长。这个项目调查了工资变化对上述人口变化的贡献。为此，构建了agent年龄不同的模型。性别、教育。工资，以及他们生活的家庭类型。经纪人寻找配偶，决定婚姻状况和生育决定，并投资于孩子的教育。该模型经过校准，以复制70年代中期的经济和人口特征。接下来，只研究绝对和相对（跨性别和教育水平）工资变化的模型，看看人们生活的家庭类型的变化有多少可以追溯到工资的变化。这个项目可能会产生深远的影响。最近一系列实证文献的发现表明，这些因素发生在生命早期。在16岁之前，人们一生成就的差异占了大部分。此外，孩子成长的家庭类型似乎对这些成就的形成起着重要的作用：父母双方都在场的孩子比父母一方单独的孩子更成功。这意味着，观察到的家庭结构的巨大变化可以塑造下一代美国人的特征，不仅在他们的平均成就方面，而且可能以更戏剧性的方式塑造不平等的特征。了解产生家庭类型变化的机制似乎是一项非常重要的任务。该项目的第二部分试图了解各国财富和生产力的差异如何影响他们选择的税收政策类型。贫穷国家的税收与富裕国家相比如何？为什么美国对资本的征税比欧洲更密集？为了回答这些问题，研究者开发了一个模型，在这个模型中，政府对自己的公民是仁慈的，并选择如何以不同的税率通过不同形式的税收（公司税、个人劳动收入和资本税）来最好地收集收入。此外，这些政府不能承诺未来的政策，他们可以随时改变主意。在这个模型中，富国和穷国的政府政策是相互关联的，因为资本可以在各国之间流动。该项目的这一部分可能还会对政府协调政策是否是个好主意的问题提供一些新的启示。

This project consists of two parts concerned with the determinants as well as the implications of inequality both between people and across countries. The first part studies recent rather dramatic changes in the composition of U.S. households. Between the mid seventies and the beginning of the nineties the share of non-married females grew dramatically in the U.S. (from 17% to 30% in the 30 to 44 age group). At the same time that people are living less as married couples. there has been a steady increase in out of wedlock child-raising that increased the share of single mothers from 12%o to 17% of the total female population, while total fertility remained constant over the same period. There has been another major change in the sane time period: the structure of wages is much different now than twenty five years ago. There has been a modest increase in average wages. together with fairly large increases in the ratio of wages of college to non-college educated and in the ratio of women's to men's wages. This project investigates the contribution of the changes in wages to the aforementioned demographic changes. To this end, a model is constructed where agents differ in age. sex, education. wages, and in the type of family they live. Agents search for a mate, make marital status and fertility decisions and invest in their children's education. The model is calibrated so that it replicates the economic and demographic characteristics of the mid seventies. Next, the model is studied with only changes in wages, absolute and relative (across sexes and education levels) to see how much of the changes in the type of family that people live in can be traced back to changes in wages. The project may have far reaching implications. The findings of a recent body of empirical literature indicate that factors that happen early in life. before age 16, account for most of the differences in lifelong achievements of people. Moreover, it seems that the type of family where children grow up contributes significantly to shape those achievements: the presence of both parents yields more successful children than one parent alone. This implies that a change in household structure of the magnitude observed can shape the characteristics of the next generation of Americans, not only in terms of their average achievements, but probably and in a more dramatic fashion, for the characteristics of inequality. Understanding the mechanisms that generate the changes in family type seems to be a very important task.The second part of the project attempts to understand how differences in the wealth and productivity of nations affect the type of taxing policies that they choose. How do taxes of poorer countries compare to those of richer countries? Why does the U.S. tax capital more intensively than Europe? To answer these questions the investigator develops a model where governments are benevolent towards their own citizens, and choose how to best collect revenue thorough different forms of taxation (corporate taxation, and personal labor income and capital taxation) at different rates. Moreover, these governments cannot commit to future policies, they can always change their mind. In this model government policies of rich and poor countries are interrelated since capital can flow across countries. This part of the project might also shed some new light on the issue of whether it is a good idea that governments can coordinate their policies.