The study of trends in income inequality has flourished in recent decades, enabled by a rich and growing variety of data sources providing trend information on populations and individuals with significant detail on characteristics, income, education, occupation, and other such measures. On the contrary, the study of trends in social mobility— defined as “intergenerational mobility” or the association between (1) the social standing of an individual’s family of origin (when the individual is growing up), and (2) the social standing of that same individual when she or he is an adult— has languished largely because the data necessary to assess whether it is being realized are lacking.
The study of mobility matters because it speaks to issues of class formation, equal opportunity, and lifetime inequality. For mobility scholars oriented toward issues of class formation, the presumption has long been that high levels of social mobility, manifested both within and across generations, hamper the formation of social classes. That is, insofar as individuals judge that their lives will likely be lived out in their class of origin, they will come to identify with that class and even act (e.g., vote, protest, strike) on its behalf. The correspondingly rigid boundaries between classes further allow distinctive class cultures and lifestyles to develop and harden.
In recent years, the interest in social mobility has been sparked by a growing interest in equality of opportunity—examining the extent to which children born into different families have different life chances and outcomes. It is important to understand such barriers to mobility because
of the long-standing and, to some extent, distinctively American commitment to free and open competition in the labor market. The main question is whether the United States is indeed living up to this commitment. The commitment to equal opportunity is one of the most cherished national objectives. Consistent and comprehensive data are necessary to monitor the strength of that commitment at regular intervals.
The purpose of this workshop was to plan a new national survey that will provide the first definitive evidence on recent and long-term trends in social mobility. In order to facilitate the design of a new data collection and analysis source, the workshop had the objectives of coming to an understanding of the substantial advances in the methods and statistics for modeling mobility, in survey methodology and populationbased survey experiments, in opportunities to merge administrative and survey data, and in the techniques of measuring race, class, education, and income. The workshop also focused on documenting the state of understanding of the mechanisms through which inequality has been generated in the past four decades.
In the absence of a survey designed and dedicated to the collection of information to assess the status of social mobility, a wide variety of data sources designed for other purposes have been pressed into service in order to illuminate the state of social mobility and its trends. The workshop reviewed each of the various sources that could be exploited for the purpose of securing trend measurements. The options considered in the workshop included conventional suggestions, such as to enhance the Panel Study of Income Dynamics with a much larger sample size or perhaps to bolster the General Social Survey (GSS) or Survey of Income and Program Participation (SIPP) in various ways. The SIPP, for example, might regularly include an intergenerational module, while the GSS could include a ramped-up measure of parental income and other family origin variables that meet standard criteria. Another option would be to design and deploy a stand-alone survey through a university-based survey research organization, such as the Survey Research Center at the University of Michigan, Ann Arbor, or via a privately held survey organization, such as Westat Corporation.
The workshop was presented information that enabled an evaluation of these options on using such criteria as cost, quality of data, availability of relevant variables, and the likelihood of becoming a viable source of ongoing trend data. Fielding new surveys or scaling up existing ones would incur high costs when compared to the alternative of leveraging existing large federal surveys operated by the Census Bureau. Thus, the ongoing Current Population Survey and the American Community Survey emerge as prime candidates. Here, too, workshop participants had the task of presenting information that would permit comparing
these two options and documenting the main considerations in choosing between them.
Finally, the workshop aimed to consider the best possible ways to link administrative and other records to the survey data that participants would propose to collect. There are several possibilities for linking administrative records, including (1) securing parental income reports from earlier decennial Census data by ascertaining, within the context of the proposed survey, the name and address of the parents (at the time the respondent was growing up); (2) securing parental earnings or income reports from archived Internal Revenue Service (IRS) or Social Security records by ascertaining the requisite parental identifying information (within the proposed survey); (3) linking to IRS or Social Security records for the purpose of securing income or earnings reports for the respondents; and (4) drawing on administrative educational records (i.e., tests, grades, college attended, major) for the respondents.
The National Research Council appointed a steering committee of experts in the study of social mobility that was charged with:
organizing an open workshop on the key decision points associated with launching a new national level survey of social mobility. The workshop will bring together scientific experts from a variety of social and behavioral disciplines to consider various aspects of a major new national survey, including identifying relevant new theoretical perspectives and technical issues that have implications for modeling, measurement, and data collection. A variety of invited presentations will explore various aspects of survey design, statistical power, instrument choice, variable choice, and analytical approach. The information contained in these presentations, together with the general discussion at the workshop, will be captured and will form the basis of an individually authored summary of the event that will be prepared by a designated rapporteur. Following the preparation of the workshop summary, a smaller group of experts will be convened to digest the key themes that emerged from the workshop and identify the way forward.
The steering committee was mindful that the issues associated with the study of social mobility are complex and, over the years, have often been seen as intractable largely because of a dearth of relevant data. It was not possible to discuss all aspects of social mobility and its measurement in a one-day workshop, so the steering committee identified a set of key topics and invited experts to prepare background papers on these topics. The presentations at the workshop meeting were designed to shed light on various aspects of considering and developing a new survey of social mobility. Robert Hauser, executive director of the National Research Council’s Division of Behavioral and Social Science and Education, briefed the workshop on the evolution of research interest in the
topic of social mobility and the interest of the sponsor, the National Science Foundation, in the topic. An overview of the state of social mobility research was presented by Michael Hout, who stated that understanding social mobility calls for understanding of the circumstances of birth and upbringing, as well as parents’ attributes. He submitted that any survey of social mobility would need to capture this information. Following these overview presentations, David Grusky, Timothy Smeeding, and Matthew Snipp discussed how social mobility has changed over time and postulated reasons for these changes.
A discussion of the various ways in which social mobility is modeled and measured was presented by Florencia Torche. This presentation was buttressed by an extensive discussion and evaluation of data sources for measuring mobility, both survey-based and using administrative data, presented by Rob Warren.
Six presentations on various topics to be considered in any measures of social mobility rounded out the workshop. Henry Brady, Robert Mare, Bhash Mazumder, Chandra Muller, Laura Tach, and Steve Trejo focused on measures of political participation, social networks, labor market, education, family composition, and immigration, respectively. A spirited discussion of the lessons learned from these presentations and the way ahead for developing a data collection program to support an understanding of social mobility trends and impact completed the workshop.
Following the workshop, the steering committee was reconvened to weigh the discussion, identify additional areas in which research and pretesting may be needed, and begin the task of developing a proposal for a national mobility survey. Immediate next steps include publication of the background papers prepared for the workshop. Ultimately, any decisions on the next steps will be reached in close discussion with a wide variety of key actors such as the Census Bureau Director and possible funders of the new data collection.