經濟多元化與生產力差距決定因素:中美洲各國 1990–2010之實證研究

Abstract

Central American (CA) countries are considered to be part of the developing world. Their small and open economies have historically relied on the production and exports of agricultural products. In the last two decades, even though the share of agriculture in the GPD has declined significantly facing the surge in shares of manufacturing and service sectors, agriculture remains as one of the major economic activities in the CA countries. Agricultural sector employs a large portion of the economically active population and is an important source of income, particularly for rural and unskilled labor force. Significantly diversified economic performance has been observed among the seven CA countries during the past decades. Among them, Costa Rica and Panama are the most developed in terms of per capita GDP and outperformed the other five countries in various social-economic indicators, whereas Honduras and Nicaragua are the least developed. Identifying the sources contributing to observed differences among the CA countries has important implications for policy makers in their pursuit of economic growth. Therefore, this thesis attempts to examine two important issues for the seven CA countries – economic diversification and its link to economic growth as well as sectoral productivity differences – during the period 1990-2010. We first examine the economic diversification and its possible relation to economic growth. In the second part of the thesis, we then move to analyze the factors leading to differences in the labor productivity of industrial and agriculture sectors. According to Esanov (2012), economic diversification can be categorized into the product or export diversification. Both these two types of diversification are considered to enhance economic growth. To measure diversification, the trend of GDP composition by sector is used as a measure of product diversification while Herfindahl-Hirschman Index (HHI) is calculated to measure export diversification. The empirical results in this study suggest that the diversification strategy in the CA region is country-specific, Costa Rica and Panama experienced significant achievements while the other five countries seem to be lagged. Export diversification has been achieved mostly within the same agricultural sector but not among sectors; CA countries have introduced new export products into their export basket, but those new products mainly come from agricultural sector. In addition, the levels of diversification experienced by the CA countries are significantly lower compared to the developed economies. Based on regression analysis controlling for year and country specific unobserved characteristics, this study provides empirical evidence supporting the positive association of export diversification and per-capita-GDP growth. In the second part of the thesis, determinants contributing to observed differences in labor productivity between the industrial and agriculture sectors are analyzed through a two-stage regression model. The data collected indicates that, during 1990-2010, the level of labor productivity in the industrial sector has been higher and growing at a greater speed in comparison with the agricultural sector. A systematic review of the literature suggests that this sectoral productivity gap can be explained by variables such as physical capital investment, openness of the economy, foreign direct investment (FDI) as well as education (human capital). To test the hypothesis that those variables have a greater effect in industrial sector than in agricultural sector, which consequently implies a wider gap in labor productivity, a structural equation model is constructed. The specification in our econometric model explicitly considers possible problem of endogenous explanatory variable. The regression results suggest physical capital investments, openness and education are the major drivers to widen up the gap of labor productivity in the industrial and agriculture sectors. As a reasonable proxy for knowledge spilled into the CA countries from the developed countries, FDI is found to have a diminishing effect on productivity differences; it is a determinant of productivity differences at low level of FDI, but it reduces the productivity differences at large enough level of FDI inflow. Study sectoral labor productivity differences is of special significance in Central America, because these countries have labor-intensive economies and both agricultural and industry sectors together employ a large share of the economically active population. Due to its small share in the world economy, Central America has often been left out in researches on topics related to economic growth. To the best of our knowledge, there has not been previous literature on economic diversification and sectoral productivity differences in the CA countries as a whole. In this regard, this thesis fills in the gap and thus represents a significant complement to literature on the region.