This paper responds to growing evidence that neighborhood inequality cannot be fully captured at a single point in a child’s life, or even in a single generation in a family’s history. In this sense the analysis builds on recent research showing that a large majority of African-American families living in today’s most disadvantaged residential areas are the same families that occupied the most disadvantaged neighborhoods in the 1970s, suggesting that neighborhood inequality should be conceptualized and studied as a multigenerational process (Sharkey 2008
This observation complicates theoretical perspectives and empirical approaches to understanding the impact of neighborhoods on individuals. The evidence presented here suggests that a multigenerational perspective is crucial to understanding the relationship between neighborhood environments and cognitive ability. A family’s exposure to neighborhood poverty over two consecutive generations is found to reduce the average child’s cognitive ability by more than half a standard deviation. Further, we find strong evidence that a parent’s childhood neighborhood environment influences her children’s cognitive ability, a generation later. This finding is consistent with the idea that the parent’s own childhood environment may influence the parent’s child through its impact on the parent’s educational attainment, occupational choices, income, marriage partner, and mental health. Through these and any number of additional pathways, it is plausible that the effect of parents’ neighborhood environments on parents’ adult outcomes may linger on to impact the next generation. We stop short of assessing the role of specific mechanisms in mediating the effect of parent’s childhood neighborhoods on their children’s cognitive ability because of the methodological problems inherent in mediation analysis (Sobel 2008
). The goal of this paper is to establish the existence of multigenerational causal effects of neighborhood poverty in the first place, and hence suggests the investigation of the relative importance of specific causative mechanisms is an important goal for future research.
Direct comparison to previous research is complicated because most previous studies examine the effects of more severely concentrated poverty. Our race-specific analyses using more severe thresholds to define high-poverty neighborhoods are more directly comparable to the treatment effects under study in Moving to Opportunity (Kling et al. 2007
; Sanbonmatsu et al. 2006
), two natural experiments in Chicago (Jacob 2004
; Ludwig et al. 2009
) and in the Sampson et al. (2008)
study in Chicago. Among African-Americans, we find large effects of extreme poverty in the child’s environment on both broad reading scores and on applied problems scores, although the effects have wide confidence intervals. The magnitude of our estimated effect on reading scores is similar to estimates from Sampson et al.’s (2008)
study of verbal ability among a sample of African Americans in Chicago, and is somewhat larger than estimated effects from the Kling et al. (2007)
sub-analysis of African Americans in MTO and the Ludwig et al. (2009)
analysis of African Americans in Chicago. Estimated effects on applied problems scores are comparable to the estimates on math scores from Ludwig et al. (2009)
, and are larger than those found in studies from MTO and from Jacob (2004)
, all of which report null effects on math/applied problems assessments.
Before discussing the implications of these findings, we must acknowledge several limitations. Most importantly, causal inference about multigenerational neighborhood effects from observational data necessarily relies on strong assumptions about the absence of unobserved selection bias, specifically the assumption of sequential ignorability. This includes the assumption that respondents select into neighborhoods only on the basis of factors observed by the analyst, or factors strongly correlated with these observed factors. Our empirical strategy addresses this limitation in two ways. First, we estimate marginal structural models that rely on assumptions of sequential uncounfoundedness that are weaker than the assumptions necessary in the corresponding conventional regression models. Second, we perform a novel formal sensitivity analysis for the totality of unobserved confounding that explores two broad selection scenarios and find that the estimates for the multigenerational joint effect of neighborhood poverty reported in this study are substantially robust to quite strong violations of the unconfoundedness assumption.
A second set of limitations is that the structure of the PSID data forced us to make decisions in the analysis design that are less than ideal. First, parental neighborhood environment is necessarily measured for only one parent—the parent that was in the PSID sample during childhood. Second, although this is the first study to assess the multigenerational nature of neighborhood effects, we must follow previous work in measuring the neighborhood environment within each generation over a relatively short period (here, three years). This may lead our estimates to understate the true effects of sustained neighborhood disadvantage, as Wodtke, Harding, and Elwert (2010)
demonstrate in an analysis of neighborhood effects using detailed year-by-year residential trajectories in the single-generation context. Third, because parents give birth at different ages, there is substantial variation in the duration of the gap between measurement of neighborhood conditions in each generation. Finally, in an effort to retain as many cases as possible, our specifications include children from a wide age range. Retaining most children assessed in the CDS allows us to estimate multigenerational neighborhood effects more precisely and to conduct race-specific analyses, but it compromises our ability to make any claims about the developmental timing of neighborhood effects. However, supplementary analyses reported above indicate that the multigenerational joint effects of neighborhood poverty are substantial even within narrower age ranges.
With these limitations in mind, we believe that the notion of multigenerational neighborhood effects points to a revised, broader, conceptualization of how the neighborhood environment influences cognitive ability, and furthermore suggests a revised theoretical and empirical perspective on the influence of social contexts on child development. We argue that this revised perspective should inform interpretations of experimental and quasi-experimental research assessing the impact of neighborhood change arising from residential mobility, as well as observational research on social contexts and child development.
First consider the experimental and quasi-experimental evidence available from residential mobility programs, including the Gautreaux program in Chicago, the Moving to Opportunity experiment, and other similar programs (Briggs 1997
). In all such programs, participants (typically low-income families living in public housing) are provided the chance to move to less disadvantaged environments, frequently in the same city or within the metropolitan area. Research based on these programs exploits exogenous variation in the destinations of participants in the programs to estimate how a change in the neighborhood environment impacts child and adult social outcomes. While this type of study provides sound evidence on the causal effect of contemporary
neighborhood exposure due to a change in the neighborhood environment arising from a residential move, by design these studies do not capture the lagged or cumulative
effects of previous neighborhood environments.
This focus on contemporary neighborhood circumstances has been questioned in recent research on youth in Chicago, which shows that the impact of living in severely disadvantaged neighborhoods continues to be felt years later (Sampson et al. 2008
). The challenge is strengthened considerably when one considers the possibility of generation-lagged effects or cumulative, multigenerational effects. A change in a family’s neighborhood may bring about an abrupt and radical change in the social environment surrounding children, but this change may be a short-term departure from a familial history of life in disadvantaged environments. The shift in context may improve the opportunities available to adults and children, the child’s peers and school environment, and the parent’s mental health, but it may not undo the lingering influence of the parent’s childhood environment. In short, a temporary change of scenery may not disrupt the effects of a family history of disadvantage.
This assessment should not be taken as a critique of the residential mobility literature, but as a lens with which to interpret it. Evaluations of residential mobility programs provide powerful evidence for policy-makers interested in designing programs to move families into areas that may improve adults’ mental health or children’s life chances. But these programs tell us little about the cumulative disadvantages facing a family living in America’s poorest neighborhoods over long periods of time, unless the residential move creates a lasting change in the neighborhood environment that persists over multiple generations. The Moving to Opportunity program did not produce this type of change in families’ environments. The initial drops in neighborhood poverty among families in the experimental group have faded quickly, due to moves back to high-poverty neighborhoods and rising poverty in the destination neighborhoods of experimental group families (Clampet-Lundquist and Massey 2008
; Kling et al. 2007
If the most powerful effects of neighborhoods stem from exposure in prior generations, as our evidence indicates, it is perhaps not surprising that research from mobility programs has produced inconsistent and relatively small impacts.
Next consider the extensive literature on neighborhood effects based on observational data. The most common analytic approach in this literature involves estimating neighborhood effects while controlling for a set of family background measures. A common claim made in reviews of these studies is that the family environment is more important for child development than the neighborhood environment (Ellen and Turner 1997
; Leventhal and Brooks-Gunn 2000
). A multigenerational perspective suggests that such a conclusion is misleading. Aspects of family background that are linked with child developmental outcomes, such as parental income or education, may be endogenous to neighborhood conditions in the prior generation. Parents’ educational attainment, economic position, and health are better thought of as partial outcomes of their own earlier residential circumstances. In this sense, individuals and families inseparably embody
neighborhood histories, and it is therefore a mistake to think of the family and the neighborhood as competing developmental contexts. Our multigenerational perspective thus amplifies and acts upon recent calls to revisit the classics and question the neat separation of individuals and contexts. Writes Entwistle et al. (2007
, p. 1498): “The literature has become preoccupied with whether contextual effects exist given a competition between individual and neighborhood effects. Blau’s (1960)
essential insight, that contextual effects operate through, and in concert with, individual effects, is little in evidence.”22
Our theory and our results indicate that the family and the neighborhood environments are closely intertwined, combining to influence the developmental trajectories of individuals in ways that extend across generations. As we have shown, a multigenerational perspective is essential to understanding inequality in cognitive ability. Our findings support other studies showing a link between the neighborhood environment and children’s cognitive ability, but we extend this literature by calling attention to the history of social environments occupied by family members over generations. This approach reflects the broader implication of this paper, which is that to understand inequality, in cognitive ability and in other developmental domains, it is not sufficient to focus on a single point in a child’s life, or even a single generation of a family. Instead, we must understand the history of disadvantages experienced over generations of family members. This approach recognizes the complex ways in which lives are linked across generations (Elder, Johnson and Crosnoe 2003
), so that disadvantages or advantages experienced in one generation may linger and add to the disadvantages or advantages experienced by the next. Uncovering the ways in which disadvantages compound over time is central to developing a more complete understanding of the maintenance and reproduction of inequality.