Table 4.
Explaining Population Density in 1 CE
| (1) | (2) | (3) | (4) | (5) | (6) | |
|---|---|---|---|---|---|---|
|
| ||||||
| OLS | OLS | OLS | OLS | OLS | IV | |
|
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| Dependent Variable is Log Population Density in 1 CE
|
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| Log Years since Neolithic Transition | 1.560*** (0.326) | 1.903*** (0.312) | 1.930*** (0.272) | 2.561*** (0.369) | 3.459*** (0.437) | |
| Log Land Productivity | 0.404*** (0.106) | 0.556*** (0.081) | 0.394*** (0.067) | 0.421*** (0.094) | 0.479*** (0.089) | |
| Log Absolute Latitude | −0.080 (0.161) | −0.030 (0.120) | 0.057 (0.101) | 0.116 (0.121) | 0.113 (0.113) | |
| Mean Distance to Nearest Coast or River | −0.685*** (0.155) | −0.418 (0.273) | −0.320 (0.306) | |||
| Percentage of Land within 100 km of Coast or River | 0.857** (0.351) | 1.108*** (0.412) | 1.360*** (0.488) | |||
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| Continent Dummies | Yes | Yes | Yes | Yes | Yes | Yes |
| Observations | 128 | 128 | 128 | 128 | 83 | 83 |
| R-squared | 0.47 | 0.41 | 0.59 | 0.69 | 0.75 | 0.72 |
|
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| First-stage F-statistic | – | – | – | – | – | 10.85 |
| Overid. p-value | – | – | – | – | – | 0.590 |
Summary – This table establishes, consistently with Malthusian predictions, the significant positive effects of land productivity and the level of technological advancement, as proxied by the timing of the Neolithic Revolution, on population density in the year 1 CE, while controlling for access to navigable waterways, absolute latitude, and unobserved continental fixed effects.
Notes – (i) log land productivity is the first principal component of the log of the percentage of arable land and the log of an agricultural suitability index; (ii) the IV regression employs the numbers of prehistoric domesticable species of plants and animals as instruments for log transition timing; (iii) the statistic for the first-stage F-test of these instruments is significant at the 1 percent level; (iv) the p-value for the overidentifying restrictions test corresponds to Hansen’s J statistic, distributed in this case as chi-square with one degree of freedom; (v) a single continent dummy is used to represent the Americas, which is natural given the historical period examined; (vi) regressions (5)-(6) do not employ the Oceania dummy due to a single observation for this continent in the IV data-restricted sample; (vii) robust standard error estimates are reported in parentheses; (viii) *** denotes statistical significance at the 1 percent level, ** at the 5 percent level, and * at the 10 percent level, all for two-sided hypothesis tests.