تجارت بین المللی و پویایی های اقتصاد کلان : مورد تجارت دو جانبه آمریکا با کشورهای G-7

The short- and long-run effects of exchange rates, income, interest rates and government spending on U.S. bilateral trade with the other G-7 countries are investigated using an autoregressive distributed lag (ARDL) model. The primary contribution of this study is to consider separating the analysis of exports and imports in an integrated model that empirically encompasses four major schools of thoughts – elasticity, Keynesian income, absorption and monetary approaches – in order to identify macroeconomic linkages to U.S. bilateral trade with the other G-7 countries accurately. Results suggest that, in both the short- and long-run, U.S. imports and exports are highly sensitive to changes in U.S. and foreign income, while U.S. imports and exports are relatively insensitive to changes in bilateral exchange rate. It is also found that both exports and imports are more responsive to changes in government spending than changes in interest rates in both the short- and long-run.

The theories analyzing the relationship between macroeconomic variables and the trade balance generally can be classified into four approaches: (1) elasticity approach; (2) Keynesian income approach; (3) absorption approach; and (4) (international) monetary approach (Whitman, 1975, Dornbusch, 1975 and Frenkel and Johnson, 1977). The elasticity approach argues that the exchange rate plays a key role in determining the trade balance. The Keynesian income approach claims that the growth in domestic income relative to foreign income causes deterioration in the trade balance. The absorption approach, on the other hand, suggests that, since the trade balance is equal to the difference between the GDP (how much is produced) and the domestic absorption (how much is consumed domestically), an increase (decrease) in GDP (domestic absorption) improves the trade balance. Both monetary and fiscal policy directly influences the domestic absorption. Finally, given the belief that the trade balance is essentially a monetary phenomenon, the monetary approach claims that the rapid growth of money supply relative to that of the rest of the world is a major culprit behind the trade balance deficit. A number of studies have examined the effects of macroeconomic variables on bilateral trade between the United States and its major trading partners (for example, Rose and Yellen, 1989, Backus, 1993, Bahmani-Oskooee and Brooks, 1999, Blonigen, 2001, Breuer and Clements, 2003, Bahmani-Oskooee and Ratha, 2004, Bahmani-Oskooee and Hegerty, 2008, Bahmani-Oskooee and Wang, 2009 and Kim, 2009). Until recently, however, studies tackling this issue have typically relied on a trade model in which a country's trade balance is only related to a measure of (domestic and foreign) income and exchange rates; hence, they generally fall into the first two approaches. Backus (1993), for example, examines the effects of changes in exchange rates and income on the trade balance between the U.S. and Japan; he finds that real depreciation of the U.S. dollar improves the trade balance. Recently, Bahmani-Oskooee and Wang (2009) use disaggregated trade data to identify the dynamics of exchange rates and income on the composition of bilateral trade between the U.S. and Australia; they conclude that both U.S. exports and imports response to exchange rate changes. Accordingly, relatively little effort has been made to construct an empirical model in which the trade balance is related to other relevant macroeconomics factors such as fiscal and monetary policy related variables in addition to exchange rates and income. In other words, no study has empirically modeled all four major schools of thought in examining macroeconomic linkages to the trade balance between the U.S. and its major trading partners. In this study, therefore, we attempt to extend the scope of previous work by examining the effects of macroeconomic variables on U.S. bilateral trade in an integrated model that encompasses all four schools of thought together. The empirical focus is on identifying the short- and long-run effects of exchange rates, income, interest rates and government spending on bilateral trade of aggregated commodity groups (e.g., agricultural goods, chemicals and materials, machinery and transport equipment and manufactured goods) between the U.S. and each of the other 6 members of the group of seven industrialized countries (G-7)—Canada, Japan, France, Germany, Italy and the United Kingdom (UK). For this purpose, an autoregressive distributed lag (ARDL) approach to cointegration (ARDL) (Pesaran et al., 2001) is applied to quarterly data for 1989–2011. The remaining section presents the empirical model, data, empirical results, and concluding remarks.

The primary contribution of this study is to examine macroeconomic linkages to U.S. bilateral trade in an integrated model that empirically encompasses all four major schools of thought—that is, elasticity, Keynesian income, absorption and monetary approaches. The empirical focus has been on identifying the short- and long-run effects of exchange rates, income, interest rates and government spending on bilateral trade of four commodity groups – agricultural goods, chemicals & materials, machinery & transportation equipment and manufactured goods – between the U.S. and each of the other 6 members of the G-7 – Canada, Japan, France, Germany, Italy and the UK. For this purpose, the ARDL is applied to exports and imports separately in order to measure the effects of macroeconomic variables on the trade balance accurately. The results show that U.S. imports and exports are highly responsive to changes in income in the U.S. and the other G-7 countries in both short- and long-run, while U.S. imports and exports are relatively insensitive to changes in bilateral exchange rate in both the short- and long-run. We also find that both U.S. exports and imports seem to be relatively more responsive to changes in government spending than changes in interest rates in both the short- and long-run.