Table 7.
Robustness to Direct Measures of Technological Sophistication
| (1) | (2) | (3) | (4) | (5) | (6) | |
|---|---|---|---|---|---|---|
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| OLS | OLS | OLS | OLS | OLS | OLS | |
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| Full Sample | Full Sample | Income Sample | Income Sample | Income Sample | Income Sample | |
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| Dependent Variable is: | ||||||
| Log Population Density in: | Log Income per Capita in: | Log Population Density in: | ||||
| 1000 CE | 1 CE | 1000 CE | 1 CE | 1000 CE | 1 CE | |
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| Log Technology Index in Relevant Period | 4.315*** (0.850) | 4.216*** (0.745) | 0.064 (0.230) | 0.678 (0.432) | 12.762*** (0.918) | 7.461** (3.181) |
| Log Land Productivity | 0.449*** (0.056) | 0.379*** (0.082) | −0.016 (0.030) | 0.004 (0.033) | 0.429** (0.182) | 0.725** (0.303) |
| Log Absolute Latitude | −0.283** (0.120) | −0.051 (0.127) | 0.036 (0.161) | −0.198 (0.176) | −1.919*** (0.576) | −2.350*** (0.784) |
| Mean Distance to Nearest Coast or River | −0.638*** (0.188) | −0.782*** (0.198) | −0.092 (0.144) | 0.114 (0.164) | 0.609 (0.469) | 0.886 (0.904) |
| Percentage of Land within 100 km of Coast or River | 0.385 (0.313) | 0.237 (0.329) | −0.156 (0.139) | 0.092 (0.136) | 1.265** (0.555) | 0.788 (0.934) |
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| Continent Dummies | Yes | Yes | Yes | Yes | Yes | Yes |
| Observations | 140 | 129 | 26 | 29 | 26 | 29 |
| R-squared | 0.61 | 0.62 | 0.64 | 0.30 | 0.97 | 0.88 |
Summary – This table demonstrates that the relatively small effect of the level of technological advancement on income per capita in the years 1000 CE and 1 CE, but its significantly larger effect on population density in the same time periods, remains qualitatively robust when direct measures of technological sophistication for the corresponding years are used in lieu of the timing of the Neolithic Revolution.
Notes – (i) the technology index for a given time period reflects the average degree of technological sophistication across communications, transportation, industrial, and agricultural sectors in that period; (ii) the almost perfect collinearity between the degree of technological sophistication in the agricultural sector and the timing of the Neolithic transition does not permit the use of the latter as a covariate in these regressions; (iii) 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; (iv) a single continent dummy is used to represent the Americas, which is natural given the historical period examined; (v) regressions (3)–(6) do not employ the Oceania dummy due to a single observation for this continent in the corresponding regression samples, restricted by the availability of income per capita data; (vi) robust standard error estimates are reported in parentheses; (vii) *** 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.