Appendix C: Gravity Model Variables and Supplementary Results | RDP 2010-08: Sources of Chinese Demand for Resource Commodities

RDP 2010-08: Sources of Chinese Demand for Resource Commodities Appendix C: Gravity Model Variables and Supplementary Results

Ivan Roberts and Anthony Rush

November 2010

Table C1: List of Variables Used in Regressions
Coefficient	Description
	volume of bilateral resource imports by country i from country j
α_t	time dummy intercept, specific to year t and common to all trading partners
α_ij	country-pair fixed effect, a dummy variable for each pair of trading partners in all years (note that α_ij ≠ α_ji)
GDP_it	real GDP of country i at time t
pop_it	population of country i at time t
X_it	real exports of country i at time t
(GNE–M)_it	real gross national expenditure less imports of country i at time t
M_it	total real imports of country i at time t
(GNE+X)_it	real gross national expenditure plus exports of country i at time t
I_it	real gross capital formation of country i at time t
(GDP–I)_it	real GDP less gross capital formation of country i at time t

Table C2: Gravity Model Results for Resource Imports
	Baseline			Developing country effect
	(1)	(2)	(3)	(1A)	(2A)	(3A)
GDP_jt	0.71^***	0.78^***	0.72^***	0.71^***	0.78^***	0.72^***
GDP_it	1.67^***			1.48^***
GDP_it ×Developing_i^(a)				0.24^**
X_it		0.98^***			0.96^***
X_it ×Developing_i^(a)					−0.05
(GNE–M)_it		0.13^***			0.01
(GNE–M)_it ×Developing_i^(a)					0.33^***
I_it			0.52^***			0.28^***
I_it ×Developing_i^(a)						0.39^***
(GDP–I)_it			0.98^***			1.07^***
(GDP–I)_it ×Developing_i^(a)						−0.22^*
pop_jt	0.00	−0.08	0.02	0.02	−0.09	0.03
pop_it	0.08	0.88^***	0.24	0.00	0.79^***	0.20
Adjusted R²	0.75	0.76	0.75	0.75	0.76	0.75
Observations	85,025	79,867	85,006	85,025	79,867	85,006
Notes: Model estimated with robust standard errors. , , ** represent statistical significance at the 10, 5 and 1 per cent levels respectively. Data cover bilateral trade between 180 economies over the period 1980–2008. Country-pair fixed effects and time-fixed effects are included in all regressions, but omitted from this table. Resource imports are excluded from aggregate imports (M). (a) An economy is classified as developing if it does not appear on the World Bank's list of ‘high-income economies’. Note that the list of developed and developing economies does not change over the sample.

Table C3: Gravity Model Results for Resource Imports
Alternative decomposition of GDP into *GNE*+X and M
	Baseline		China effect
	(1)	(2)	(1A)	(2A)
GDP_jt	0.71^***	0.71^***	0.72^***	0.72^***
GDP_it	1.67^***		1.40^***
GDP_it×Chinai			0.88^***
M_it		0.18*		0.20**
M_it×China_i				0.34
(GNE+X)_it		1.24^***		1.00^***
(GNE+X)_it×China_i				0.43
pop_jt	0.00	0.01	−0.01	−0.02
pop_it	0.08	0.57^***	0.86^***	0.70^***
Adjusted R²	0.75	0.75	0.75	0.75
Observations	85,025	85,025	85,025	85,025
Notes: Model estimated with robust standard errors. , , ** represent statistical significance at the 10, 5 and 1 per cent levels respectively. Data cover bilateral trade between 180 economies over the period 1980–2008. Country-pair fixed effects and time-fixed effects are included in all regressions, but omitted from this table. Resource imports are excluded from aggregate imports (M).