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Long Run Outcomes of Child Labor
Stephanie Chapman∗
November 2, 2015
Abstract
In this paper I estimate the long term individual effect of child labor using a linked cen-sus sample from 1900 and 1910 to 1940. The sample consists of over 730,000 males fromthe US birth cohorts of 1884 to 1904. To solve the fundamental identification problem thatstarting work later implies higher school achievement under compulsory education laws, I usea difference in difference strategy to exploit both changes in minimum working age laws andcompulsory school start ages across 14 states. I find that the effect of starting work a year earlier- controlling for missed school - is an increase of $8 of annual income in 1940. While modest,this effect is roughly the same as the marginal benefit of an extra year of school controlling forage of allowed labor market entry. This implies that families during this time period were likelyoptimally allocating the time of work eligible children between work and school. To conclude,I discuss the implications of this research for modern policy design aimed at eradicating childlabor in developing countries. In particular, modern policy must account for the benefits ofwork to children if they intend to improve the welfare of those children.
1 Introduction
As many as 20% of American children aged 10-14 were gainfully employed in various indus-
tries in the late 19th and early 20th centuries, and while much has been done to study the short
term determinants and effects of child labor in modern developing nations, the long term ef-
fects of working as a child have not yet been examined. The rhetoric surrounding the effort to
abolish child labor in the early twentieth century focused on the detrimental effects of work-
ing, particularly missed school attendance and negative health outcomes, though it is not clear
∗I gratefully acknowledge assistance and comments on this paper from Matthias Doepke, Diane Schanzenbach, LeeLockwood, Seema Jayachandran, Lori Beaman, David Figlio and participants in the 501 graduate student seminar. Myparticular thanks go to Joe Ferrie for his assistance with the US census files and for many helpful comments. All errorsare mine.
1
whether these fears were well-founded. If work were a response to extreme poverty, children
may be better off working than they would have been otherwise.
In this paper I develop an empirical strategy to separately identify the confounded effects of
working as a child and completing less education as a result of starting work earlier. Between
1880 and 1910, most states in the US implemented and/or changed both child labor and com-
pulsory schooling laws. Since compulsory entry ages and minimum working ages both change
the amount of education a child was required to receive, but only the latter changed both the
amount of education and work experience ex-post, they can be combined to produce separate
estimates of the effect of an extra year of school and an extra year of work experience on labor
market productivity in the long term. To this end I collected a panel of compulsory entry ages
and minimum working ages from several sources, both contemporary and historical.
Using a census sample linked from initial observations in 1900 and 1910 to outcomes in
1940, I demonstrate that once education is adequately controlled for there is a benefit to starting
work at a younger age. In fact the reduced form increase in income from an additional year
of legal work, holding schooling constant is about $7-$8 of annual income. The reduced form
effect of an extra year of schooling, holding work start age constant, is about $5-$7 of annual
income. While these effects are quite small, they are remarkably significant considering the
effects are observed when individuals are in their prime working years, between the ages of 40
and 60. These estimates also imply that children - or their parents - may have been rationally
allocating their time, inasmuch as the long term estimates of the impact of an extra year of
education is roughly equal to the long term impact of an extra year of schooling.
The question of what lasting effects child labor may have and through which channels those
effects operate is not just a question of historical curiosity, but also one of interest to modern
policy makers. Concern has been growing over child labor in developing nations (Edmonds
2007), but little work can be done on long run outcomes due to the fundamental data limitation
that in order to examine long run outcomes, the researcher must observing individuals long
after their work and schooling decisions have been completed. In this paper I speak to the mod-
ern policy questions about child labor by addressing the long term individual consequences of
2
restricting child labor. The results of this paper reveal that allowing children to work at younger
ages may have long term benefits for their labor market productivity. In particular, these results
indicate that simply outlawing child labor may have negative long term consequences at the in-
dividual level, beyond the negative general equilibrium consequences outlined in the theoretical
literature on this topic (Doepke and Zilibotti 2005; Basu and Van 1998).
This paper proceeds as follows. Section 2 will address the historical background, the liter-
ature in this field and how this project fits into the literature. Section 3 discusses the potential
theoretical effects that working at young ages may have on children, as well as discussing the
channels of those effects. Section 4 describes the data that will used and section 5 outlines the
identification strategy. Section 6 describes and interprets the results, while section 7 concludes
by describing the relevance of these results for the modern policy debate over child labor, and
by describing future avenues of research.
2 Literature Review
It was not until the late nineteenth century that child labor in the US came to be seen as detri-
mental to children. In colonial America the virtues of hard work at all ages were extolled, and
children were encouraged to contribute to the family economy at as early an age as possible.
Early textile mills and factories in New England were largely staffed by women and children,
while men tended the family farms. A shift occurred in the national consciousness, however,
as children were more frequently employed outside the home away from their parents, and as
the jobs they performed were perceived as becoming more dangerous (Abbott 1908). When
the 1900 census showed an increase from the previous census in the number of children aged
10-14 engaged in gainful occupations, activists mobilized to lobby for child labor legislation
across the country, founding the National Child Labor Committee in 1904 (Hindman 2002).
Speaking to the questions plaguing many activists at the time, Moehling (2004) uses US
data from Bureau of Labor Statistics household surveys 1917-1919 to show that families with
working children and young adults (ages 10-24) had different expenditure patterns relative
3
to households with fewer or without working children, demonstrating that children may have
enjoyed individual monetary benefits of working at young ages even though wages were largely
turned over to parents each pay period. This paper suggests support for positive income effects
impacting working children.
Most states passed or changed their child labor laws between 1880 and 1920. The extent
to which those laws were effective remains an empirical question, though it has been exam-
ined by several authors in recent times. Moehling (1999) demonstrates that child labor laws
(specifically, newly implemented minimum working age requirements) did not contribute to
the long-term decline in the rate of child labor, though she examines only one parameter of the
laws, and gives no particular attention to determining which laws may have been enforced. It is
clear that some of the laws were never intended to be enforced, but rather passed in reaction to
and in order to appease the national child labor movement. For instance, the legislation passed
in North Carolina was written and presented to the legislature by the textile manufacturers, the
chief employer of minors in that state (Hindman 2002). In support of the effectiveness of labor
laws passed during this period Puerta (2011) uses manufacturing data from the early 20th cen-
tury to show that industrial growth of the glass industry - historically dependent on child labor
- is lower in states with more restrictive child labor policies in the Ohio River valley, though
the extent to which this is due to endogenous choices of manufacturers is unclear.
Margo and Finegan (1996) demonstrate using laws during this period that compulsory ed-
ucation laws were only statistically effective in states with compatible labor laws. The finding
that compatible education and labor laws produce a binding constraint on behavior is replicated
by Angrist and Acemoglu (2000) and Moehling (1999), implying that the labor laws were more
binding than their counterparts requiring school attendance. Another possible interpretation is
that these laws were more effectively enforced in states in which laws were designed to be
compatible.
Recent papers have challenged the validity of previous studies of compulsory schooling
laws, repeating the analyses with different empirical approaches, or higher quality data. Clay,
Lingwall and Stephens (2012) find that compulsory schooling laws had a significant impact on
4
schooling and income using similar data to mine, though only looking at the introduction of
new schooling laws rather than marginal changes in the laws. They find that laws introduced
between 1880 and 1927 had a significant impact on enrollment and attendance, and they find
using 1940 census data that laws introduced between 1898 and 1927 had a significant impact
on schooling achieved and earnings, outcomes I also examine. They estimate the return to
an additional year of schooling induced by these changes to be 8-10%. Stephens and Yang
(2014), however, challenge the results of previous papers using a “common trends” assumption
at the national level to identify the effects of changing compulsory education and child labor
laws using the 1905 to 1954 birth cohorts. They find that including region-specific time trends,
rather than national time trends, eliminates many of the returns to education implied by previous
research, suggesting that the gains found were a result primarily of unobserved regional trends,
rather than of schooling itself as was previously thought. For the analysis presented in this
paper I use primarily regional data, so this concern should be ameliorated.
Empirical studies using modern data focus primarily on the determinants of supply of child
labor, for instance showing that families in Ecuador will respond to cash transfers by reduc-
ing the labor supply of children by more than the value of the transfer (Edmonds and Shady
2012). Several authors have examined the tradeoff between work and school, concluding that
for most children in their studies, work and school (or studying at home) are not strong substi-
tutes (Akabayashi and Psacharopoulos 1999; Ravallion and Wodon 2000; Basu, Das and Dutta
2010), though in each of these studies complementary compulsory school laws were not in
place. While I will assume in this paper that there is a strict tradeoff between work and school,
in each of the states examined there are overlapping minimum working age and compulsory
schooling laws. As such, my estimates will be of the effect of delaying labor market entry by
an additional year when the legal environment necessarily requires that year be spent in school.
This will be useful in the modern policy debate, as long as any policy aimed at reducing child
labor also involves measures towards encouraging or mandating school attendance.
Interestingly, Ravillion and Wodon (2000) and Basu, Das and Dutta (2010) conclude from
their results that parents are rationally allocating their chilren’s time, a finding that I will repli-
5
cate in the long term to the extent that I find that the returns to an additional year of school and
the returns to an additional year of work are statistically indistinguishable.
Very few studies have yet examined the individual outcomes of child labor, and even fewer
attempt to examine long term outcomes. Beegle, Dehejia and Gatti (2009) examine the out-
comes of children after five years, and find that while children who worked are less likely to
still be in school and have achieved less education than their peers, they are twice as likely to
be working for wages. In their setting of rural Vietnam working for wages1 is associated with a
higher standard of living within the village, indicating that after five years, children who were
working initially are better off than their peers. They interpret these results as demonstration of
positive returns to work experience, though it is not clear to what extent the results are driven
by a natural age-income profile or by sample selection.
The paper in the development literature most closely related to this study examines long
term effects of child labor on adult income using survey data from Brazil that contains the
self reported labor market entry ages of adult men (Emerson and Souza 2007). They find
that there is a detrimental effect of starting work at young ages, but that at the entry age of
about 12 the effect reverses, and starting work earlier is beneficial later in life. This paper
is closely comparable to mine, however their approach is not as clean as my identification
strategy, as they simply make use of covariates to control for heterogeneity among individuals
in the determinants of their labor supply as children.
My paper will add to the current literature by examining heretofore difficult to asses long
term outcomes and by employing a novel strategy to cleanly identify whether children working
the US in the early part of the twentieth century were positively or negatively affected by their
work as children. In doing so I will add to the literature on compulsory education and child
labor in the US by providing an estimate of the returns to education and the returns to early
work experience. I will also contribute to the modern policy debate surrounding child labor in
developing countries by providing an estimate of the relative importance of school versus work
for those children who are most vulnerable. This information will inform policy makers of the
1as opposed to being a self-employed farmer
6
types of policies that should be adopted to optimally affect the long term welfare of impacted
children.
3 Theoretical Background
It is not ex-ante clear whether banning child labor would result in improved long run outcomes
for the child, particularly when children are often working as a reaction to poverty experienced
by the family. The negative effects of child labor are well understood, though perhaps not as
well documented. Because of the time allocation problem of the child, a choice must be made
between school, work and leisure, so more work necessarily means less school or less leisure
time. Working will be detrimental to the child to the extent that he is missing school, or missing
leisure time that might be fundamental to childhood experiences. Additionally, if he is sent to
work in a dangerous job, there may be some long term negative effects such as diminished
labor capacity from severed limbs or injured lungs.
The positive effects of working are less obvious, but could perhaps be stronger than the
negative effects. There is a pure income effect from working: more labor means more income
and thus more consumption in the household. In the contexts in which child labor is debated,
families are often suffering from extreme poverty. While policy makers are well-intentioned,
on that margin families may be making a choice between sending a child to work and everyone
in the family eating, or sending that child to school and sacrificing the subsistence level of
consumption the income from the child would have brought to the family. Even if the family
made the hard decision to send a child to school despite the income loss, there are documented
connections between malnutrition and cognitive performance. Attending school under such
circumstances would likely have diminished the returns to education relative to the baseline
of an appropriately nourished child, which could have long run implications for the child’s
productive capacity.
If income effects dominate, it is also possible that there are strong spillover effects within
the household. It is documented empirically that children who were working during the time
7
period I study turned most of their earnings over to their parents (Moehling 2004). While the
children retained some private value from their earnings, most of the benefit was likely enjoyed
at the household level, thus the work of one child would positively impact the rest of the (non-
working) household members. In this way, the benefit to a single child of working at a young
age is an underestimate of the social value the work could generate, particularly within the
framework of the household.
Beyond the pure income effects, there could be returns to work experience for the child that
could benefit him in the long run. This latter effect may especially be true of particular kinds
of work, such as apprenticeships. Finally, given that child labor is a household level decision,
it could be the case that there is selection among children in the household, and that those who
are employed at young ages are exactly those who would no longer benefit from additional
years of schooling. If this is the case, those children would certainly be better off continuing to
work rather than attending school. The ambiguity of theoretical channels through which labor
as a child may affect children highlights the need for an empirical study of these questions.
4 Data
Several sources are leveraged to develop the data set used in this project. The population of
boys in the US birth cohorts of 1884 to 1904 are linked based on their names, birth state and
birth years to match observations in 1900 and 1910 to outcomes in 1940, resulting in a sample
aged 36-56 in 1940. The IPUMS representative sample of the 1910 census is used to construct
county level control variables. Finally, the education and labor laws are collected from a variety
of sources in order to identify exogenous shifters of individual school going and labor market
entry behavior.
8
4.1 Linked census samples
The linked census samples are constructed based on mathching the first and last names of each
individual as well as their state and a fuzzy match on their year of birth2. This results in over
700,000 observations. The 1884 to 1900 birth cohorts are taken from the 1900 to 1940 linkage,
while the remaining birth cohorts of 1901 to 1904 are taken from the 1910 to 1940 linkage. For
the purposes of this paper I will restrict the sample to those observed in fourteen states in the
upper Midwest and New England in their childhood3.
There is some evidence that the linking process results in a sample that is generally more
well-off than a representative sample would be. The most likely explanation for this bias in the
linking process is that those who were members of more literate and wealthy families in 1900
are more likely to have consistent data reported in the 1900 and 1940 censuses, and are thus
more likely to be matched and thus observed in this data set. If anything, this bias will work
against me because those that are most likely to have benefited from starting work at an earlier
age - those from poorer families in 1900 and in 1910 - are more likely to not be observed in my
sample.
There are over 730,000 individuals living in the fourteen states used to this analysis in 1900
and 1910 with non-missing income observations in 1940, which represents about 10% of the
total male population of the appropriate ages in the selected states. The median individual in
this data set has an eighth grade education, while over 95% have at least a fifth grade education
(of those that report education achieved by 1940). The upper quartile of reporting individuals
have 12 years of education while the top 10% report 16 years of school, or a college education.
The median individual reports $1000 of annual income in 1940, though a significant proportion
of individuals (approximately one third) report zero income. 99% of individuals report income
less than $5000, while 99.9% report income less than $10,000. To reduce the incidence of
extreme outliers, I drop observations greater than $10,000.
2up to +/- two years of their year of birth reported in 19403Those states are: Connecticut, Maine, Massachusetts, Rhode Island, Vermont, New Hampshire, New York, New
Jersey, Pennsylvania, Michigan, Indiana, Illinois, Wisconsin and Ohio
9
4.2 IPUMS samples - County level variables
Representative samples of the US censuses have been digitized for public use. I used the 1910
IPUMS 1% sample to construct a percent urbanization and percent farm variable at the county
level to be used as control variables. Because the minimum working age laws were directed
specifically at non-farm occupations such as manufacturing, it is likely that more urbanized
counties will be differentially affected by the changing labor laws.
4.3 Education and labor laws
Data on education and labor laws are collected from four different sources. Information on
child labor laws, the minimum ages they implied, the years in which they changed and the fines
that they allowed is available in a spreadsheet compiled by Rebecca Holmes and published on
the website of Price Fishback. Ogburn (1912) contains information on whether the laws present
in each of the states included a provision for any sort of enforcement of the law, including a
categorization of the types of officials that are empowered to enforce the laws.
In all fourteen of the states examined here, the labor laws provided for special inspectors
and/or truant officers that were empowered to enforce both the child labor legislation and the
education legislation. I have used this information to define states that have “strong” labor laws
as those which have laws that provide both for fines and some sort of inspection or enforcement
of the law. It is clear both from current research and from contemporaneous accounts that
the effectiveness of the laws passed in this period differed widely across states, which could
contribute to the findings so far that child labor laws contributed little to the long run decline in
child labor over the first half of the twentieth century.
For the school entry ages required from 1880-1899, I used selected reports of the Depart-
ment of Education from 1885-1905. These reports were compiled by the Department of Ed-
ucation on a yearly basis, though the salient compulsory education ages were not reported by
state in all years. In order to fill in the gaps, I assumed that if two reports listed the same entry
ages in non-contiguous years and those years were sufficiently close together4, there were no
4In particular I was able to find reports of the compulsory entry ages at roughly three year intervals.
10
changes in the laws in the intervening years. I added to this panel the school entry ages avail-
able in the data on Claudia Goldin’s website. Although some states had compulsory schooling
laws that specify school leaving ages inconsistent with the minimum working ages, I assume
throughout that the minimum working ages are the binding legal variable. A common theme
in the literature on compulsory schooling laws during this period (Margo and Finegan, 1996;
Angrist and Acemoglu, 2000) is that compulsory schooling laws were only effective in states in
which they were paired with an age compatible labor law, implying that the binding constraint
on school leaving was the outside option of the student rather than the legal imperative to stay
in school.
From these data I distill a number of variables. Given the year each law was passed and
the provisions of those laws, I assign to each child the minimum working age and the required
school entry age to which they were subjected. For instance, if a child turned 13 the year a state
changed their minimum working age from 12 to 13, I consider his relevant minimum working
age to be 12, rather than 13. From those two variables I calculate the required years of school
for each child as the difference between the minimum working age and the required school
entry age. If there is no minimum working age, I consider the required years of school to be
zero, even if there is a compulsory schooling law in the state at that time.
Table 2 lists the states included in my sample and features of their minimum working age
laws, while table ?? lists the states included and features of their compulsory school entry age
laws. In particular I will use fourteen states in New England and the Upper Midwest to iden-
tify the effects: Connecticut, Maine, Massachusetts, Rhode Island, Vermont, New Hampshire,
New York, New Jersey, Pennsylvania, Michigan, Indiana, Illinois, Wisconsin and Ohio. Of
these fourteen states, all had preexisting minimum working age requirements and compulsory
schooling laws, so all of the variation is generated from marginal changes in the minimum
working ages and mandatory entry ages. The minimum working ages range from 10-15, while
the compulsory entry ages are either 7 or 8. Of the fourteen states considered, 10 changed their
minimum working ages (Maine, Massachusetts, New Hampshire, Rhode Island, Vermont, New
Jersey, Pennsylvania, Michigan, Ohio and Wisconsin) while 5 changed their compulsory en-
11
trance ages (Connecticut, Maine, New York, Indiana and Michigan). The maps in figures 3 and
4 summarize this information. Note that of the states that changed their laws, only 2 changed
both laws in the time period examined (Maine and Michigan), and there was a delay between
the passage of the two laws, so there are cohorts in each state differentially affected by the two
different laws5.
5 Identification
The fundamental identification problem in examining the long run outcomes of child labor is
two-fold: identifying the effect of starting work sooner and identifying the effect of staying in
school longer. To the extent that joint compulsory school and child labor laws were coordinated
enough to induce a choice between work and school only rather than work, school and leisure,
the choice of whether to start work earlier involves a direct tradeoff between more work and
less school. To address this problem, I will use two sources of variation: changes in minimum
working ages and changes in compulsory school entry ages. Changes in the former induce
variation in both amount of school attained and labor market entry age, while changes in the
latter induce variation in schooling achieved only. Several other papers use similar sources of
variation (Lleras-Muney 2002, 2005; Acemoglu and Angrist 2000), though none during this
time period or in the same way as I use them.
5.1 Intuition: Case of CT and MA
For intuition, consider the case of Connecticut and Massachusetts. In 1902 both states altered
one of those two margins. Connecticut lowered their compulsory entry age from 8 to 7, while
Massachusetts raised their minimum labor age from 13 to 14 in the same year. This situation
is illustrated in figure 1. Children born prior to 1888 in both states were subject to six years
of compulsory schooling, in Connecticut between the ages of eight and fourteen and in Mas-
sachusetts between the ages of seven and thirteen. These children will serve as a control group.
5Maine changed the minimum working age in 1907, and the school entry age in 1902, while Michigan changed theminimum working age in 1885 and the school entry age in 1904
12
Although the laws are changed in the same year, different birth cohorts are affected since more
children will have aged out of being affected by the change in the compulsory entry age in
Connecticut, while older children will still be affected by the change in the minimum working
age in Massachusetts. For children born between 1888 and 1895, those in Massachusetts will
be subject to seven years of compulsory schooling, while those born in Connecticut will be
subject to six years of compulsory schooling. Comparing these children to those in the control
group (born prior to 1888), would give the confounded estimate of both the effect of an extra
year of school and the effect of starting work a year later, since the difference being identified
is the difference between a child getting six years of education in Connecticut throughout the
time period with a child in Massachusetts getting six years of education in the pre-period, but
seven years of education in the post-period by virtue of the fact that he is starting a year later.
This can be seen clearly in the first panel of figure 2, which shows the symbolic represen-
tation of comparing the birth cohort of 1887 with the birth cohort of 1891. In this diagram, the
α’s are state fixed effects and the β ’s are birth cohort fixed effects. δ is the marginal effect
of starting work a year later only (separate from the effect of an extra year of school), while
γ is the marginal effect of getting an extra year of education. If we difference across the two
columns of this diagram, we eliminate the birth cohort fixed effects, and if we difference down
the rows of this diagram we eliminate the state fixed effects. What is left is the marginal effect
of starting work a year later (δ ), confounded with the marginal effect of gaining an extra year
of school (γ). This illustrates the fundamental identification problem with studying changes in
child labor laws only: delaying labor market entry by a year necessarily increases educational
attainment by a year, to the extent that children are required to be in school at the early teen
ages if they are not working. As a result, another source of variation in compulsory years of
education is required to separately identify the effect of starting work a year later and the effect
of requiring an additional year of schooling.
Looking at children born after 1895 gives us a way to look at the effects of these two
margins separately. Notice in figure 1 that all children born after 1895 in both Connecticut
and Massachusetts are subject to seven years of compulsory education, but how the two states
13
arrived at seven years of education from six occurs on different margins. Comparing children
born in 1896 to those born in 1891 uncovers the pure marginal effect of an extra year of school.6
The diagram detailing the difference in difference estimates can be seen in the second panel of
figure 2. Here we see that when differencing across columns and rows, we are left with γ only,
the marginal effect of an additional year of schooling.
In principle, we could then take a third difference across these two sets of cohorts to elim-
inate the effect of an extra year of schooling, leaving only the effect of starting work a year
later. In practice, this is the same as comparing the birth cohort of 1896 to the birth cohort of
1887 directly, as can be seen in the third panel of figure 2. In this case, differencing across the
columns eliminates both birth cohort fixed effects and the effect of schooling, since children
in both states during each time period are subject to the same amount of education (six years
in 1887 and seven years in 1891). Differencing across the rows then eliminates the state fixed
effects, leaving only the estimate of the effect of starting work a year early, independently of
the effect of gaining an extra year of school.
5.2 Full Empirical Model
There is considerable cross-state and time series variation in these laws during this time period,
so this approach can be expanded to include more states. In particular I am considering birth
cohorts from 1884 to 1904, who would have been affected by educational law changes from
roughly 1890 to 1910, and labor law changes from 1898 to 1918 or so. Of the 49 relevant
legal divisions present in the Union during this time period (45 states, 3 territories and the
District of Columbia in 1900), 36 passed laws regarding their minimum labor age laws, 22 of
which induced marginal changes in the minimum legal working age (i.e. raising or lowering
the existing threshold rather than implementing a minimum age where there previously was
none). There was a similar volume of activity in compulsory schooling laws, with 24 states
passing laws relevant to compulsory entry ages, 10 of which were marginal changes.
6This assumes that the benefit of an extra year of school at the beginning of the school career is roughly equivalentto the benefit of an extra year of school at the end of the school career. During this time period I find this a plausibleassumption, though I will discuss it in greater detail in subsequent sections
14
To replicate the difference in difference approach described over several observational units,
I will use state and birth cohort fixed effects with two policy- related independent variables. The
first is the minimum working age relevant to each group at the cohort × state level, denoted
by MLAst . The coefficient on this variable (δ below) will give the marginal effect of delaying
labor market entry by one year, independently of the effect of attending school for an additional
year. The second is the compulsory years of schooling variable discussed above, denoted by
CY Sst , namely the difference between the minimum working age and the compulsory school
start age relevant to each individual. The coefficient on this variable (γ below) will give the
marginal effect of an additional year of compulsory schooling only. Both of these estimates
are specific to those who are induced to change their behavior by the change in the law. The
relevant empirical specification is then
yist = αs +βt +δMLAst + γCY Sst +X ′istλ + εist (1)
where αs are state level fixed effects, βt are birth cohort fixed effects and the vector Xist contains
possible individual level control variables. In this paper I will use income in 1940 and highest
grade achieved by 1940 as outcome variables. Throughout I will assume that minimum working
age laws were more binding than school leaving ages, so the years of compulsory schooling
will be the difference between the compulsory school entry age and the minimum legal working
age.
For this approach to be valid, I make several assumptions about the structure of the problem.
First is the general “common trends” assumption made in all difference in difference specifica-
tions, that any trends seen at the birth cohort level are common across all states studied. While
there is some evidence that this may not nationally be true in this setting, there is evidence that
it is true regionally (Stephens and Yang 2014) and in this paper I will use only regional data
from New England and the upper Midwest.
I assume that the age-income profile of individuals is common across states and cohorts,
that is, that the underlying function transforming education and work experience into income
in 1940 is not specific to either the state or birth cohort. Additionally I assume that there is no
15
income effect of staying at home longer when younger, and that an extra year of school gained
at younger ages has the same marginal benefit as an extra year gained at older ages. That is,
I assume that the benefit of additional school on the staying home/school attendance margin
is the same as the benefit of additional school on the school attendance/labor market entry
margin. During this time period this seems a reasonable assumption, since presumably a new
early education curriculum was not being introduced when the school entry age was lowered,
but rather material was added to the end of the course of study. There is some concern that the
age at which children enter school has some sort of differential effect beyond the curriculum
taught in school, though this is something that may be investigated further in the literature on
returns to education.
Finally, I assume that the timing of the passage of compulsory education and minimum
labor age laws is sufficiently exogenous for it to seem random to individuals. Given that I am
studying individual birth cohorts, this assumption is plausible. Although the broader national
trends were towards the passage of these and similar laws, whether the law was passed in one
year or the next (and thus affected one birth cohort or the next younger cohort) should be
relatively random.
5.3 Interaction Effects: Empirical Model
There is reason to believe that some of these effects may be stronger or weaker in some areas
rather than in others. For instance, Fagernas (2014) finds that in states with birth registration
laws, minimum working age legislation was twice as effective at reducing the incidence of
children working. For this reason, I will consider whether the effects found vary by whether
the individual would have been subject to a birth registration law in his home state.
The empirical model for these effects is as follows
yist = αs +βt +ηBRst+δMLAst +ρ1MLAst ×BRst
+γCY Sst +ρ2CY Sst ×BRst +X ′istλ + εist
(2)
In this specification, δ and γ will still give the separately identified marginal effects of starting
16
work a year later and being subject to an additional year of compulsory schooling, respectively,
while η will give the effect on income and/or education of living in a state and birth cohort that
is subject to a birth registration law. Similarly, ρ1 and ρ2 will give the additional effect of being
on the margin of an additional year of school or a year less of work while also being subject to
a birth registration law.
6 Results
Table 3 shows that after controlling for the number of compulsory years of school, which takes
both the minimum labor age and the compulsory entry age into account, the minimum labor
age has no residual effect on the highest grade achieved by adulthood in the 1940 census. This
significant, if modest, effect on the highest grade achieved that is robust to the inclusion of
urbanization and farm percentage controls, as well as to the inclusion of interaction effects
for living in a state and birth cohort that is subject to a birth registration law. The effect of
an increase of one year of school required is about 0.04, or 4% of a year of school achieved,
which is comparable to the result of 5% of a year of school achieved for every additional
year of compulsory schooling found in Lleras-Muney (2005). Note that the effect of raising
the minimum working age and raising the compulsory school attendance age have effects of
roughly equal magnitude in columns 3 and 4 and are both significant, giving support to my
critical assumption that changes on each of these margins lead to similar changes in educational
attainment.
Table 4 shows the results of my core difference in difference specification. The coefficient
on the minimum labor age is the marginal effect on income in 1940 of living in a state which
mandates delaying labor market entry by one year, independent of the effect stemming from
an additional year of schooling, while the coefficient on required school years is the effect of
living in a state which requires an additional year of schooling on income in 1940, independent
of the implied effect of delaying labor market entry by an additional year. Changes in both of
these policy variables have marginally significant effects on income in 1940. An extra year of
17
work independent of years of schooling results in about an $6-$8 increase in income, while
an increase in the required years of school, independent of the labor market effects, results in
about a $5-$7 increase in income.
These effects are concentrated in states with birth registration laws. In those states, an
additional year of school required translates to an additional $20-$26 of annual income in 1940.
The negative effect of delaying labor market entry is also stronger for individuals affected by
a birth registration law: there is a significant negative effect of $29-$36 of annual income in
1940. Again for these specifications the effect of an additional year of school is of roughly
equal magnitude as the effect of delaying work for an extra year, implying that on the margin
an extra year of school may have carried roughly equivalent value in the long run as an extra
year of work.
While the marginal effects are modest, some perspective can be gained from examining the
largest possible change in policy variables given the ranges observed in the sample. The most
permissive working and school entry ages are 10 and 8, respectively, while the most restrictive
observed are 15 and 7. Changing from the first regime to the second would imply an increase in
the minimum working age of 5 years, and a change in the implied years of required schooling
of 6. From the results observed, that would result in an increase in highest grade achieved
by about 20% of a grade level. The effect on income is composed of a decrease of $40 per
year from missed work opportunities, but an increase of approximately $42 per year from the
increased school years, highlighting the result that in this time period, work and school seem
to be somewhat interchangeable.
Examining the results on logged income in 1940 in table 5 highlights that the effects on
individuals affected by birth registration laws may be operating on a different margin than the
the main effects. Studying logged income necessarily restricts attention to individuals who
have positive income in 1940. In these specifications the main effects are much stronger than
the interaction effects for individuals affected by birth registration laws, implying that the birth
registration laws may be operating more on the extensive margin of inducing individuals to
still be working in 1940, rather than operating on the intensive margin of increasing income for
18
those individuals affected by the laws. While the effects of an additional year of school and
delaying work by a year are still statistically similar, there is a larger gap between them in this
specification. This may imply that the negative effect of delaying work is concentrated on the
intensive margin, while the positive effect of additional years of schooling may be operating
more on the extensive margin, improving individuals’ probability of continuing to find gainful
employment in 1940.
The main result from this analysis is that it seems that delaying labor market entry for
one year has a negative effect on long run income that is roughly equal to the positive effect
of inducing an additional year of school for the same children. One possible explanation for
this result is that the first years of work may have “looked” more like school, in that children
were learning skills and trades in arrangements such as apprenticeships. Alternatively, it could
simply be the case that those children who were at risk to have their school going and labor
market behavior shifted by the changes in the laws are rationally situated on that margin. That
is, because the returns to an extra year of school and an extra year of work are approximately
the same, children who were at risk to be shifted by legislative changes were indifferent about
the exact age of labor market entry, at least on the financial margin of their long term labor
market returns. Collecting further information from the 1900 and 1910 census manuscripts
could shed light on this curious result, particularly since the recorded occupations of working
children could be used to assess the extent to which children engaged in apprenticeship-like
arrangements are driving the results.
7 Discussion
It is clear from the preceding results that there are positive effects of working and of attending
school, implying that the naive policy of simply banning child labor may have negative effects
on the most vulnerable citizens: the children such legislation is intended to protect. Any policy
maker concerned with reducing child labor should take into account the benefits children gain
from work and design their policies accordingly. For instance, a policy promoting both work
19
and school (by requiring school attendance for a work permit) would harness both of the effects
demonstrated here in the same direction, rather than forcing the effects to work in opposition.
Further work can be done on this topic to determine the exact mechanisms driving the
positive result uncovered here. Such research would further inform the types of policies that
could be undertaken in order to optimally benefit working and non-working children. At a
very local level this empirical approach can be used to examine differences between siblings
by including a family fixed effect. To the extent that each sibling’s working or school going
status is independent of the others, running this regression with a family fixed effect instead
of the state or time fixed effect would reveal the marginal effects of an extra year of school or
work on later life outcomes controlling explicitly for unobserved family characteristics.
It is possible, however, that whether children should work is a household level decision that
has household level consequences with potential spillover effects on siblings. To explore that
possibility I plan to examine whether each child’s outcome variables are related to his siblings’
work opportunities. It is easy to imagine that there would be household level income effects
of a single child working. In this case the difference between siblings in working households
would be diminished, rendering the family fixed effects approach less useful, however this
approach could afford a way to examine the mechanisms behind a positive effect of work. If
it is primarily an income effect, then there should be a similarly sized effect on non-working
siblings within a household. If, however, the effect primarily stems from work experience, on
the job training or a similar effect, then it should be private to the individual and not affect
siblings to the degree that a pure income effect would.
Of course, these approaches assume relatively random assignment of children within the
household to work and school, regardless of age or skill level. Beegle, Dehejia and Gatti (2009)
demonstrate that this may not be the case, that families in Vietnam may be systematically
sending smarter children to work, presumably to maximize the short term earning potential of
the family. Determining how to sort out these selection effects is a topic for future work, but a
topic of vital importance for policy design.
The results here demonstrate that there are positive returns to both work and school for
20
children that were on the margin of working when these laws were changed. This implies
that any policy aimed at reducing child labor should endeavor to at least replace the benefits
enjoyed from work by each child. Further, understanding the mechanisms at work here are
vital for constructing effective public policy in developing countries today. If the benefits to
children found here stem from work experience and are private to the individual, the program
may replicate the benefits of work by simply encouraging school attendance in addition to
work. If, however, the benefits operate primarily through an income effect channel within
the household, simply replacing the income of the child may benefit both the child and other
household members enjoying the spillover effects of the individual’s work.
Based on the dominant mechanism, a policy banning child labor may have a negative effect
understated by the effects on a single child. While the children studied here may be no worse
off in school than if they were working, if their income benefited their siblings the net benefit
of work could be far greater than the results reported in this paper. Failing to understand the
mechanisms could lead us to vastly understate the cost of a simple ban on child labor. This
underscores the necessity for further research to inform policy in the developing world today,
so we do not do more harm than good in pursuing the eradication of child labor.
21
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Journal of Sociology 14, 15-37
[2] Akabayashi, H. and Psacharopoulos, G. (1999) “The trade-off between child labour andhuman capital formation: A Tanzanian case study” The Journal of Development Studies35, 120-140
[3] Angrist, J. and Acemoglu, D. (2000) “How Large are Human-Capital Externalities? Evi-dence from Compulsory Schooling Laws” NBER Macroeconomics Annual 15, 9-59
[4] Basu, K., Das, S. and Dutta, B. (2010) “Child labor and household wealth: Theory andempirical evidence of an inverted-U” Journal of Development Economics 91, 8-14.
[5] Basu, K and Van, P. (1998) “The economics of child labor” American Economic Review88, 412-427
[6] Beegle, K., Dehejia, R. and Gatti, R. (2009) “Why should we care about child labor: theeducation, labor market and health consequences of child labor.” The Journal of HumanResources 44, 871-889
[7] Bursztyn, L. and Coffman, L. (2012) “The schooling decision: Family preferences, in-tergenerational conflict and moral hazard in the Brazilian Favelas” Journal of PoliticalEconomy 120, 359-397
[8] Clay, K., Lingwall, J. and Stephens, M. (2012) “Do Schooling Laws Matter? Evidencefrom the Introduction of Compulsory Attendance Laws in the United States” WorkingPaper
[9] Doepke, M. and Zilibotti, F. (2005) “Macroeconomics of child labor regulation” Ameri-can Economic Review 95, 1492-1524
[10] Edmonds, E. (2007) “Child Labor” Handbook of Development Economics
[11] Edmonds, E. and Shady, N. (2012) “Poverty Alleviation and Child Labor” American Eco-nomic Journal: Economic Policy 4, 100-124
[12] Emerson, P. and Souza, A. (2007) “Is Child Labor Harmful? The Impact of WorkingEarlier in Life on Adult Earnings” Working Paper
[13] Fishback, P., Holmes, R., Allen, S. and Kantor, S. Website for State Labor Laws in theEarly Twentieth Century [website listing]
[14] Goldin, C. and Katz, L. Website for Compulsory Education and Child Labor Laws byState (1900 to 1939) [website listing]
[15] Heady, C. (2003) “The effect of child labor on learning achievement.” World Development31, 385-398
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[19] Landes, W. and Solomon, L. (1972) “Compulsory Schooling Legislation: An EconomicAnalysis of Law and Social Change in the Nineteenth Century” Journal of EconomicHistory 22, 54-91
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23
Figure 1: Identification Intuition
Figure 2: Difference in difference box
Connecticut Massachusetts ∆(MA−CT )Birth cohort of 1887 αCT +β87 +14δ +6γ αMA +β87 +13δ +6γ αMA−αCT −δ
Birth cohort of 1891 αCT +β91 +14δ +6γ αMA +β91 +14δ +7γ αMA−αCT + γ
∆(Cohort1891−Cohort1887) δ + γ
Connecticut Massachusetts ∆(MA−CT )Birth cohort of 1891 αCT +β91 +14δ +6γ αMA +β91 +14δ +7γ αMA−αCT + γ
Birth cohort of 1896 αCT +β96 +14δ +7γ αMA +β96 +14δ +7γ αMA−αCT
∆(Cohort1891−Cohort1896) γ
Connecticut Massachusetts ∆(MA−CT )Birth cohort of 1887 αCT +β87 +14δ +6γ αMA +β87 +13δ +6γ αMA−αCT +δ
Birth cohort of 1896 αCT +β96 +14δ +7γ αMA +β96 +14δ +7γ αMA−αCT
∆(Cohort1896−Cohort1887) δ
24
Table 1: Compulsory school entry ages
State Initial entry age(birth year 1884)
Year of change New entry age
Connecticut 8 1902 7Illinois 7 - -Indiana 8 (1899) 1902 7Maine 8 1902 7Massachusetts 8 1899 7Michigan 8 1904 7New Hampshire 6 1896 8New Jersey 7 - -New York 8 1909 7Ohio 8 - -Pennsylvania 8 (1895) - -Rhode Island 7 - -Vermont 8 - -Wisconsin 7 - -
Table 2: Minimum labor age laws
State Initial laborlaw date
Minimum labor age(birth year 1884)
Year ofchange
New minimumlabor age
Connecticut 1872 14 1890 16Illinois 1883 14 1906 16Indiana 1897 14 - -Maine 1875 12 1907 14Massachusetts 1852 13 1902 14Michigan 1871 12 1909 14New Hampshire 1871 10 1901/1911 12/14New Jersey 1874 15 1903 14New York 1874 14 - -Ohio 1877 12 1910 15Pennsylvania 1895 12 1905 14Rhode Island 1883 12 1906 13Vermont 1867 10 1906 12Wisconsin 1879 12 1907 14
26
Tabl
e3:
Eff
ecto
ned
ucat
iona
latta
inm
ent
(1)
(2)
(3)
(4)
(5)
(6)
Hig
hgr
ade
Hig
hgr
ade
Hig
hgr
ade
Hig
hgr
ade
Hig
hgr
ade
Hig
hgr
ade
Min
imum
labo
rage
-0.0
0891
-0.0
0940
0.03
01∗∗
0.02
97∗∗
0.01
240.
0114
(0.0
154)
(0.0
156)
(0.0
091)
(0.0
091)
(0.0
156)
(0.0
157)
Com
puls
ory
scho
olin
gye
ars
0.03
90∗∗
0.03
91∗∗
0.03
80∗∗
0.03
88∗∗
(0.0
126)
(0.0
128)
(0.0
135)
(0.0
137)
Com
puls
ory
entr
yag
e-0
.038
99∗
-0.0
3910∗
(0.0
126)
(0.0
128)
1910
Cou
nty
urba
n%
0.11
10.
111
0.11
1(0
.060
7)(0
.060
7)(0
.060
7)
1910
coun
tyfa
rm%
0.69
7∗∗∗
0.69
7∗∗∗
0.69
5∗∗∗
(0.1
03)
(0.1
03)
(0.1
03)
Bir
thre
gist
ratio
nla
w1.
969∗∗
1.87
2∗∗
(0.6
66)
(0.6
67)
Bir
thre
gist
ratio
nX
-0.2
42∗∗
-0.2
28∗∗
min
imum
labo
rage
(0.0
791)
(0.0
793)
Bir
thre
gist
ratio
nX
0.15
7∗0.
145∗
com
puls
ory
scho
olin
gye
ars
(0.0
665)
(0.0
669)
Con
stan
t9.
656∗∗∗
8.96
5∗∗∗
9.65
6∗∗∗
8.96
5∗∗∗
9.48
2∗∗∗
8.79
3∗∗∗
(0.1
78)
(0.1
87)
(0.1
78)
(0.1
87)
(0.1
78)
(0.1
92)
N76
7,91
375
6,19
576
7,91
375
6,19
576
7,91
375
6,19
51
All
spec
ifica
tions
incl
ude
stat
ean
dbi
rth
year
fixed
effe
cts.
2St
anda
rder
rors
(in
pare
nthe
ses)
clus
tere
dat
the
stat
eby
birt
hye
arle
vel.
3*
p<
0.05
,**
p<
0.01
,***
p<
0.00
1
27
Table 4: Effect on 1940 income
(1) (2) (3) (4)Income, 1940 Income, 1940 Income, 1940 Income, 1940
Minimum labor age -8.432∗ -8.344∗ -5.992 -6.143(4.057) (4.187) (4.272) (4.402)
Compulsory schooling years 5.456 6.934 4.973 6.744(3.480) (3.648) (3.643) (3.875)
1910 County urban % 287.9∗∗∗ 288.0∗∗∗
(15.51) (15.51)
1910 county farm % 528.4∗∗∗ 528.0∗∗∗
(24.35) (24.35)
Birth registration law 270.8∗ 222.5(129.0) (123.7)
Birth registration X -35.94∗ -28.73∗
minimum labor age (14.32) (13.82)
Birth registration X 26.29∗ 19.76compulsory schooling years (11.38) (11.13)
Constant 1420.0∗∗∗ 750.8∗∗∗ 1406.5∗∗∗ 736.6∗∗∗
(46.12) (48.38) (49.67) (53.23)N 726,737 715,777 726,737 715,777
1 All specifications include state and birth year fixed effects.2 Standard errors (in parentheses) clustered at the state by birth year level.3 * p < 0.05, ** p < 0.01, *** p < 0.001
28
Table 5: Effect on logged 1940 income
(1) (2) (3) (4)Log(income) Log(income) Log(income) Log(income)
Minimum labor age -0.0104∗∗∗ -0.0104∗∗∗ -0.00978∗∗∗ -0.0101∗∗∗
(0.00270) (0.00280) (0.00286) (0.00296)
Compulsory schooling years 0.00596∗ 0.00726∗∗ 0.00521∗ 0.00679∗
(0.00244) (0.00258) (0.00252) (0.00271)
1910 County urban % 0.236∗∗∗ 0.236∗∗∗
(0.0121) (0.0121)
1910 County farm % 0.310∗∗∗ 0.310∗∗∗
(0.0224) (0.0224)
Birth registration law 0.110 0.0709(0.0916) (0.0900)
Birth registration law X -0.0169 -0.0115minimum labor age (0.00999) (0.00988)
Birth registration law X 0.0155∗ 0.0107compulsory schooling years (0.00775) (0.00774)
Constant 7.266∗∗∗ 6.828∗∗∗ 7.268∗∗∗ 6.832∗∗∗
(0.0304) (0.0334) (0.0332) (0.0367)N 544,413 536,916 544,413 536,916
1 All specifications include state and birth year fixed effects.2 Standard errors (in parentheses) clustered at the state by birth year level.3 * p < 0.05, ** p < 0.01, *** p < 0.001
29