Title Child Quality Over Quantity

Title Child Quality Over Quantity

Title Child Quality over Quantity


This study focuses on the “quantity-quality tradeoff” hypothesis of child-bearing and child–raising: that when parents have the ability to limit fertility, the result may be not only smaller numbers of children but also higher investment in each child’s human capital. We investigate whether and to what extent fertility decline and smaller family sizes globally and in Vietnam are making it possible for households to invest more in their children’s education—not only through leaving them in school longer, but also by increasing direct outlays on private tutoring and schooling generally.

Contact information

F. Halsey Rogers ()

Lead institution

World Bank

Countries where the research will take place

Global and Vietnam

How does the research describe the impact of population/reproductive health on poverty reduction and/or economic growth?

This study was motivated by a desire to assess the quantity-quality tradeoff, both globally and in the case of Vietnam, to understand whether in fact fertility-related policies might affect education outcomes. Specific questions to be answered include the following:

1. Does lower fertility correlate with higher expenditures on private tutoring (and private education in general) in a broad cross-section, after controlling for other factors?

2. Is there a causal relationship running from lower fertility to higher investment in tutoring (and private education more generally)?

We chose to focus on Vietnam because during that country’s two decades of rapid economic growth, its fertility rate has fallen sharply at the same time that the average educational attainment of its people has risen rapidly. We explore whether the coincidence of these two trends could be explained by parents making a tradeoff between quantity and quality of children, and whether government policies to control family size may therefore have accelerated progress in education and poverty reduction.

How will the research address a policy need, and what kind of policy lesson is expected?

A key policy need is to understand whether there is a causal relationship between a couple’s fertility choices and the level of investment in their children’s human capital. A number of studies have tried to measure the quantity-quality tradeoff as it shows up in investment in different types of human capital, including both health and education. In recent years, this literature has moved beyond establishing correlations to assessing the causal claim that parents are investing more in human capital because they can limit fertility. An alternative hypothesis is that the correlations simply reflect the fact that certain types of families are more likely to have larger numbers of children and to invest less in each child. Getting around this endogeneity problem is a major challenge in the literature, and one that we try to address through instrumenting for fertility levels. Whether the relationship is causal or not has important implications for family-planning and population policy, as it sheds light on the effects of policies like provision of health care and government-imposed restrictions on family size.

Another contribution that this study makes is to explore families’ financial investment in their children’s education, including through private tutoring. Few studies have examined this relationship, even through financial investments may be a more direct measure of investment than a child’s school enrollment. Especially given the importance of private tutoring as a parallel education sector in Vietnam and through much of East Asia, this is a major gap in our understanding.

Methods used

1) The first paper, published in the World Bank Research Observer, was a literature review that offered a critical assessment of the numerous studies on the determinants and effects of tutoring, and discussed the welfare and distributional effects of this kind of investment in human capital by parents. It paid particular attention to identifying methodologies that dealt seriously with identification issues, to establish the causal link from fertility to investment in education.

(2) The second paper, presented at the PAA meetings, used an instrumental variables approach that combined micro data from three sources, including a new survey focused on private tutoring expenditures. (See below for description.) In the analysis, the authors instrument for number of children in the household using several different instruments, including proximity and frequency of access to family planning services. The goal is to identify the effects of exogenous variation in fertility on educational investment, and particularly investment in private tutoring.

Data used

For the second (Vietnam-focused) paper, the authors helped design and implement a new survey focused on private tutoring expenditures in Vietnam. The survey was designed in collaboration with other Bank staff and academics, leveraging other funding sources. The funding from the Hewlett grant helped ensure that: (1) the survey had a sample size large enough to allow more reliable inferences about the relationship between family size and fertility; and (2) the survey could add questions to collect data on factors that could be used as possible instruments for fertility (to get around the endogeneity problems). These new data were combined with data from two other sources: the larger Vietnam Household Living Standards Survey 2006 (which includes some data on education choices but limited information on demographics, fertility, or private tutoring), and the Vietnam Demographic and Health Survey 2002 (which is smaller but includes more detailed demographic data, although no data on education expenditures).

Research results

(1) Private tutoring and its links with family size globally (first paper): Private tutoring is now a major component of the educationsector in many developing countries, yet education policy too seldom acknowledgesor makes use of it. Household income, parental education, and urban location are all associated with higher levels of tutoring in a number of countries, and that in three countries where it has been looked at, having a larger number of children in the household predicts lower levels of private tutoring expenditure. Private tutoring appears to improve student performance, in most settings, and we argue that even taking equityconcerns into account, tutoring can raise the effectiveness of the education system undercertain reasonable assumptions. We recommend ways in which government policy can maximize the benefits of private tutoring, including poor-governance environments.

(2) Causal relationship between family size and investment in tutoring and educational investment by families in Vietnam (second paper): We find that families in Vietnam do indeed invest less in the education of school-age children who have larger numbers of (minor) siblings, and that this effect holds for several different indicators of educational investment—including the child’s school enrolment, his or her attendance at private tutoring, and both the money and time spent on tutoring for that child. We are still exploring the extent to which this relationship is a causal one, through instrumenting for number of siblings using different instruments. But assuming these preliminary results are confirmed, they would imply that family planning policies in Vietnam have affected not only the number of children a family has, but also the amount invested in the education of each child and the child’s level of education attainment.

Research products

Published and unpublished papers:

  • "The Growing Phenomenon of Private Tutoring: Does It Deepen Human Capital, Increase Inequality, or Waste Resources?" (2008, with Hai anh Dang), World Bank Research Observer, 23:2, pp. 161-200.
  • “The decision to invest in child quality over quantity: Has declining fertility increased household investment in education in Vietnam?” (2009, with Hai anh Dang)

Conferences and workshops at which papers have been presented

  • 2010 PopPov Research Conference, Cape Town
  • 2009 PAA Annual Meetings, Detroit
  • Hewlett Foundation-World Bank workshop on “Fertility, Reproductive Health, and Socioeconomic Outcomes,” April 2008
  • Other internal World Bank workshops