Understanding whether criminal behavior is “contagious” is important for law enforcement and
for policies that affect how people are sorted across social settings. We test the hypothesis that
criminal behavior is contagious by using data from the Moving to Opportunity (MTO)
randomized housing-mobility experiment to examine the extent to which lower local-area crime
rates decrease arrest rates among individuals. Our analysis exploits the fact that the effect of
treatment group assignment yields different types of neighborhood changes across the five MTO
demonstration sites. We use treatment-site interactions to instrument for measures of
neighborhood crime rates, poverty and racial segregation in our analysis of individual arrest
outcomes. We are unable to detect evidence in support of the contagion hypothesis.
Neighborhood racial segregation appears to be the most important explanation for acrossneighborhood
variation in arrests for violent crimes in our sample, perhaps because drug market
activity is more common in high-minority neighborhoods.

We examine the effects of moving out of high-poverty neighborhoods on the outcomes of
teenage youth, a population often seen as most at risk from the adverse effects of such
neighborhoods. The randomized design of the Moving To Opportunity demonstration allows us
to compare groups of youth, initially similar and living in high-poverty public housing. An
“experimental” group was offered vouchers valid only in a low-poverty neighborhood; a
“Section 8” group was offered traditional vouchers without geographic restriction; and a control
group was not offered vouchers.
We study outcomes in four domains: education, risky behavior, mental health, and
physical health. Aggregating effect sizes over all of the outcomes, females in both treatment
groups benefited from the moves, while males in both treatment groups experienced worse
outcomes. Females in the experimental group experienced improvements in education and
mental health and were less likely to engage in risky behaviors. Females in the traditional
voucher group experienced improvements in mental health. Males in both treatment groups were
more likely than controls to engage in risky behaviors and to experience physical health
problems. We adopt a multiple-testing framework to account for the large number of estimates
considered. We show that the overall effects on females in the experimental group and the
effects on mental health for females in both treatment groups were least likely to be due to
sampling variation.
Families with female children and families with male children moved to similar
neighborhoods, suggesting that their outcomes differ not because of exposure to different types
of neighborhoods but because male and female youth respond to their environments in different
ways.

Families originally living in public housing were assigned housing vouchers by lottery,
encouraging moves to neighborhoods with lower poverty rates. Although we had hypothesized
that reading and math test scores would be higher among children in families offered vouchers
(with larger effects among younger children), the results show no significant effects on test
scores for any age group among over 5000 children ages 6 to 20 in 2002 who were assessed four
to seven years after randomization. Program impacts on school environments were considerably
smaller than impacts on neighborhoods, suggesting that achievement-related benefits from
improved neighborhood environments are small.

An instrumental variable can be used to identify the labor market return to schooling by
allowing comparisons between groups of individuals whose differences in schooling levels are
uncorrelated with their underlying marginal benefit from schooling and with other aspects of
unobserved ability. When the education decisions are based on individual-specific marginal
benefits and costs, there is no single rate of return for everyone in the population. This paper
demonstrates economic insights from methods interpreting instrumental variables estimates as
weighted averages of individual-specific causal effects of schooling on wages by synthesizing
existing theoretical and econometric work, and by using geographic variation in college
proximity as an example of an instrumental variable.
Characterizing the groups affected by the college proximity instrument, I find the largest
increase in schooling levels among individuals from more disadvantaged backgrounds.
Although the data is insufficient to obtain useful estimates of group-specific rates of return, I
directly compute the weight each group receives in the overall estimate. In analyzing the
response function and showing the level of schooling at which individuals change their behavior
in response to the instrument, I demonstrate that the instrument has the greatest impact on the
transition from high school to college. This corresponds to the economic intuition that changes
in the marginal cost of college should be concentrated at this transition and should not affect all
levels of schooling equally. The results suggest that disadvantaged groups are most responsive
to policies lowering college costs, and that increases in education for these groups may have high
payoff.

Rapid growth in the incarceration rate over the last two decades has made prison time a
routine event in the life course of young economically disadvantaged, black and Hispanic men.
Although incarceration may now have large effects on economic inequality, only a few studies
systematically examine the labor market experiences of ex-offenders. We review the
mechanisms that plausibly link incarceration to employment and earnings and discuss the
challenges of causal inference for a highly self-selected sample of criminal offenders. There is
little consensus about the labor market effects of a variety of justice system sanctions, but there
is consistent evidence for the negative effects of prison time on earnings, particularly among
older or white-collar offenders. The labor market effects of incarceration are not yet well
understood, but prior research suggests several promising avenues for future work.

This paper examines the short-run impacts of a change in residential neighborhood on the
well-being of low-income families, using evidence from a program in which eligibility for a housing
voucher was determined by random lottery. We examine the experiences of households at the
Boston site of Moving To Opportunity (MTO), a demonstration program in five cities. Families in
high poverty public housing projects applied to MTO and were assigned by lottery to one of three
groups: Experimental — offered mobility counseling and a Section 8 subsidy valid only in a Census
tract with a poverty rate of less than 10 percent; Section 8 Comparison — offered a geographically
unrestricted Section 8 subsidy; or Control — offered no new assistance, but continued to be eligible
for public housing.
Our quantitative analyses of program impacts uses data on 540 families from a baseline
survey at program enrollment, a follow-up survey administered l to 3.5 years after random
assignment, and state administrative data on earnings and welfare receipt. 48 percent of the
Experimental group and 62 percent of the Section 8 Comparison group moved through the MTO
program. One to three years after program entry, families in both treatment groups were more likely
to be residing in neighborhoods with low poverty rates and high education levels than were families
in the Control group. However, while members of the Experimental group were much more likely
to be residing in suburban communities than were those in the Section 8 group, the lower program
take-up rate among the Experimental group resulted in more families remaining in the most
distressed communities. Households in both treatment groups experienced improvements in
multiple measures of well-being relative to the Control group including increased safety, improved
health among household heads, and fewer behavior problems among boys. Experimental group
children were also less likely to be a victim of a personal crime, to be injured, or to experience an
asthma attack. There are no significant impacts of either MTO treatment on the employment,
earnings, or welfare receipt of household heads in the first three years after random assignment.

Incarceration directly affects a significant and increasing share of Americans, and the
lengths of new incarceration spells have increased dramatically in the past twenty years.
Employment in the legitimate, mainstream economy is a key factor in the reintegration of former
inmates into society after release. While considerable literature documents large adverse labor
market consequences of going to prison, this paper provides the first evidence focusing directly
on the effects of increases in incarceration length on the employment and earnings prospects of
individuals after their release from prison. Data on inmates are from the state system in Florida
and the federal system in California, linked to administrative records of quarterly earnings.
This paper utilizes a variety of research designs in an attempt to identify the causal
effects of increases in incarceration length: controlling for observable factors, accounting for
pre-spell differences in outcomes, and using instrumental variables for incarceration length based
on randomly assigned judges with different sentencing propensities. The results show no
consistent evidence of adverse labor market consequences of longer incarceration length using
any of the analytical methods in either the state or federal data.

The Moving To Opportunity randomized housing voucher demonstration finds virtually no significant
effects on employment or earnings of adults. Using qualitative data from in-depth, semi-structured
interviews with 67 participants in Baltimore, we find that although the voucher and control groups have
similar rates of employment and earnings, respondents’ relationship to the labor market does differ by
program group. Our analysis suggests that the voucher group did not experience employment or earnings
gains in part because of human capital barriers that existed prior to moving to a low-poverty
neighborhood. In addition, employed respondents in all groups were heavily concentrated in retail and
health care jobs. To secure or maintain employment, they relied heavily on a particular job search strategy
– informal referrals from similarly skilled and credentialed acquaintances who already held jobs in these
sectors. Though experimentals were more likely to have employed neighbors, few of their neighbors held
jobs in these sectors and could not provide such referrals. Thus controls had an easier time garnering
such referrals. Additionally, the configuration of the metropolitan area’s public transportation routes in
relationship to the locations of hospitals, nursing homes, and malls posed additional transportation
challenges to experimentals as they searched for employment – challenges controls were less likely to
face.

We estimate the post-release economic effects of participation in prison-based General
Educational Development (GED) programs using a panel of earnings records and a rich set of
individual information from administrative data in the state of Florida. Fixed effects estimates of
the impact of participating in the GED education program show post-release quarterly earnings
gains of about 15 percent for program participants relative to observationally similar nonparticipants.
We also show, however, that these earnings gains accrue only to racial/ethnic
minority offenders and any GED-related earnings gains for this group seem to fade in the third
year after release from prison. Estimates comparing offenders who obtained a GED to those who
participated in GED-related prison education programs but left prison without a GED show no
systematic evidence of an independent impact of the credential itself on post-release quarterly
earnings.

We study adult economic and health outcomes in the Moving to Opportunity (MTO)
demonstration, a randomized housing mobility experiment in which families living in highpoverty
U.S. public housing projects in five cities were given vouchers to help them move to
private housing units in lower-poverty neighborhoods. An “experimental” group was offered
vouchers valid only in a low-poverty neighborhood; a “Section 8” group was offered traditional
housing vouchers without geographic restriction; a control group was not offered vouchers. Our
sample consists largely of black and Hispanic female household heads with children.
Five years after random assignment, the families offered housing vouchers through MTO
lived in safer neighborhoods that had significantly lower poverty rates than those of the control
group not offered vouchers. However, we find no significant overall effects on adult
employment, earnings, or public assistance receipt -- though our sample sizes are not sufficiently
large to rule out moderate effects in either direction. In contrast, we do find significant mental
health benefits of the MTO intervention for the experimental group. We also demonstrate a more
general pattern for the mental health results using both treatment groups of systematically larger
effect sizes for groups experiencing larger changes in neighborhood poverty rates. In our
analysis of physical health outcomes, we find a significant reduction in obesity, but no
significant effects on four other aspects of physical health (general health, asthma, physical
limitations, and hypertension), and our summary measure of physical health was not significantly
affected by the MTO treatment for the overall sample.