The Long-Term Effects of Africa's Slave Trades - Social Sciences ...

Table 10: Robustness and Sensitivity Checks. Dependent variable is ln real
per capita GDP in 2000.
Without colonizer fixed effects With colonizer fixed effects
Omitted Observations coef s.e. N R 2 coef s.e. N R 2
None −.108 ∗∗∗ (.025) 52 .27 −.108 ∗∗∗ (.024) 52 .49
South Africa −.105 ∗∗∗ (.025) 51 .26 −.104 ∗∗∗ (.024) 51 .49
North African countries −.097 ∗∗∗ (.027) 47 .23 −.096 ∗∗∗ (.025) 47 .47
Island countries −.104 ∗∗∗ (.026) 47 .26 −.110 ∗∗∗ (.025) 47 .55
All of the above −.078 ∗∗∗ (.028) 41 .17 −.079 ∗∗∗ (.027) 41 .53
Zero export countries −.139 ∗∗∗ (.037) 39 .28 −.087 ∗∗ (.043) 39 .51
|ê i| > 2.0 −.103 ∗∗∗ (.022) 47 .33 −.109 ∗∗∗ (.021) 48 .56
|ê i| > 1.8 −.106 ∗∗∗ (.021) 46 .36 −.109 ∗∗∗ (.027) 48 .56
|ê i| > 1.5 −.096 ∗∗∗ (.021) 45 .33 −.101 ∗∗∗ (.020) 46 .58
|ê i| > 1.0 −.099 ∗∗∗ (.018) 35 .48 −.102 ∗∗∗ (.016) 35 .79
dffits −.105 ∗∗∗ (.021) 44 .37 −.108 ∗∗∗ (.022) 49 .53
Cook’s Distance −.108 ∗∗∗ (.023) 48 .32 −.108 ∗∗∗ (.024) 51 .47
Welsch Distance −.088 ∗∗∗ (.024) 50 .22 −.108 ∗∗∗ (.024) 51 .47
Notes: The dependent variable is the natural log of real per capita GDP in 2000. The
colonizer fixed effects are indicator variables for the identity of the colonizer at the time
of independence. Coefficients are reported with standard errors in brackets. ∗∗∗ , ∗∗ , and ∗
indicate significance at the 1, 5, and 10 percent levels. Influential variables were omitted
using the following standard rules. dffits: omit if dffits i > 2 √ k/n. Cook’s distance:
omit if Cook’s distance > 4/n. Welsch distance: omit if Welsch distance > 3 √ k. n is the
number of observations and k is the number of independent variables.
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