A REEVALUATION OF THE EFFECT OF HUMAN CAPITAL ACCUMULATION ON ECONOMIC GROWTH: USING NATURAL DISASTERS AS AN INSTRUMENT
Abstract
This study is a reevaluation of the effect of human capital accumulation on economic growth using natural disasters as an instrument. The total population for the study is 200 staff of ministry of economic development, Abuja. The researcher used questionnaires as the instrument for the data collection. Descriptive Survey research design was adopted for this study. A total of 133 respondents made economic advisers, economic analysts, senior staff and junior staff were used for the study. The data collected were presented in tables and analyzed using simple percentages and frequencies
CHAPTER ONE
INTRODUCTION
1.1 Background of the study
Theoretic models of economic growth suggest that human capital accumulation is a significant determinant of rising per capita income. Microeconomic evidence of the positive relationship between schooling and wages supports this prediction. Estimates using macroeconomic data demonstrate that the initial stock of human capital is an important determinant of economic growth, but empirical estimates of the effects of changes in human capital (human capital accumulation) poorly match theoretic predictions (Barro and Sala-i-Martin (1995) and Benhabib and Spiegel (1994)). Most studies approach this poor match as a measurement error problem (Temple (1999a), Mankiw, Romer, and Weil (1992), Krueger and Lindahl (2001)), including correcting for imperfect measures of quality (Hanushek and Kimko (2000), Wossmann (2003)). Other studies have focused on the effects of outliers (Temple 1999b) or the use of incorrect specifications (Englander and Gurney (1994) Gemmel (1996), Bassanini and Scarpetta (2002), Engelbrecht (2003)). These studies suggest that restricting the sample to OECD countries can generate a generally positive effect of changes in schooling or school enrollments on growth that is similar in magnitude to those found in microeconomic estimates based on survey data, but tell us little about the experience of countries outside the OECD, which are often considered to be the developing countries. Our contribution to the literature is based on the possibility that the poor match between theory and empirical work results not from how we measure human capital, but from the potentially endogenous relationship between changes in human capital and economic growth. Using data from developed and developing countries, we present evidence suggesting that human capital is, in fact, endogenously determined and therefore empirical analysis requires an instrumental variable approach. Of course, we are not the first to introduce instrumental variables to this literature. Pritchett (2001) and Krueger and Lindahl (2001) apply an instrumental variables technique to estimate the effect of changes in average years of schooling on growth, using Nehru, Swanson, and Dubey (1995) and Kyriacou’s (1991) schooling data as instruments, respectively.2 Their purpose in using the instrumental variables method is to overcome the measurement error issue, and not necessarily to address endogeneity per se. Indeed, the Nehru, Swanson, and Dubey and Kyriacou schooling variables are not appropriate instruments if one is trying to address endogeneity. A valid instrument in this context is one that determines changes in schooling but is not a direct determinant of economic growth; alternative measures of schooling are arguably just as important a determinant to growth as is the Barro and Lee measure of schooling. Furthermore, researchers like Glewwe and Hanan (2004) have shown that demand for education is positively correlated with increases in household income and wealth, thus emphasizing the two-way relationship between economic growth and human capital accumulation. It appears that a key reason that researchers have not yet addressed the endogeneity issue is because of the lack of valid instruments. To our knowledge, no studies exist in which the endogeneity of human capital accumulation is tested, and if found to be present, the instrumental variables method is used to estimate the effects of changes in human capital on growth. Skidmore and Toya (2002) demonstrate that climatic natural disasters affect growth through human capital accumulation, indicating that a climatic disaster variable may be an appropriate instrument. In the aftermath of the 2004 Southeast Asian Tsunami that killed more than 280,000 and affected millions, it is not unreasonable for economists to consider how the threat of natural disasters might affect human and physical capital decisions. Skidmore and Toya (2002) suggest that due to relatively recent advances in forecasting, climatic disasters (as opposed to geologic disasters) are primarily a threat to immobile physical capital but not mobile forms of capital such as human capital. The relative increase in exposure to risk of physical capital provides an incentive for economic agents to invest relatively more heavily in human capital. The correlation between exogenous natural disasters and endogenous investment decisions over time suggest that disasters are a valid instrument for factors that affect growth. In this paper, we use measures of the propensity for natural disasters to test for the endogeneity of schooling enrollment and changes in average years of schooling over the 1960-1990 period. We find evidence of endogeneity. We therefore employ instrumental variables techniques to estimate the effects of changes in human capital on economic growth. The instrumental variables estimation procedure yields a coefficient on human capital accumulation that is larger in magnitude than found in our OLS estimates and in most previous studies that use data from a wide range of countries and is closer to theoretic predictions. Bils and Klenow (2000) attempt to determine the causal relationship between schooling and economic growth. They point out that a common belief is that “reverse causality” or simultaneity is likely to lead to an over-estimate of the effect of human capital accumulation on growth because anticipated increases in future economic growth could cause schooling to increase.
STATEMENT OF THE PROBLEM
To our knowledge, no studies exist in which the endogeneity of human capital accumulation is tested, and if found to be present, the instrumental variables method is used to estimate the effects of changes in human capital on growth. Skidmore and Toya (2002) demonstrate that climatic natural disasters affect growth through human capital accumulation, indicating that a climatic disaster variable may be an appropriate instrument. In this background the researcher wants to investigate the reevaluation of the effect of human capital accumulation on economic growth using natural disasters as an instrument.
OBJECTIVE OF THE STUDY
The objectives of the study are;
1. To ascertain the effect of human capital accumulation on economic growth using natural disaster
2. To ascertain the relationship between human capital accumulation and economic growth
