Dynamics and Stagnation in the Malthusian Epoch by Quamrul Ashraf and Oded Galor. Published in volume , issue 5, pages of American Economic. This paper empirically tests the predictions of the Malthusian theory with respect to both population dynamics and income per capita stagnation. This paper examines the central hypothesis of the influential Malthusian theory, according to which improvements in the technological environment during the.
|Published (Last):||16 December 2007|
|PDF File Size:||7.38 Mb|
|ePub File Size:||16.37 Mb|
|Price:||Free* [*Free Regsitration Required]|
Census Bureau finds that their aggregate estimates indeed compare favorably with those obtained from other studies. National Center for Biotechnology InformationU.
Dynamics and Stagnation in the Malthusian Epoch
Indeed, the conditional correlation between technology and income per capita is not statistically different from zero at conventional levels of significance. Thus, while proximity to the equator has been found to be detrimental in the industrial stage of development, it appears to have been beneficial during the agricultural stage. Interestingly, in contrast to the relationship between absolute latitude and contemporary income per capita, the estimated elasticity of population density in CE with respect to absolute latitude suggests that economic development during this period was on average higher at latitudinal bands closer to the equator.
These findings lend credence to the empirical strategy employed by this research to test the Malthusian theory. A Simple Unified Growth Theory. First, it establishes that the onset of the Neolithic Revolution, which marked the transition of societies from hunting and gathering to agriculture as early as 10, years ago, triggered a sequence of technological advancements that had a significant effect on the level of technology in the Middle Ages.
EconPapers: Dynamics and Stagnation in the Malthusian Epoch
In line with this assertion, Table 1 reveals preliminary results indicating that an earlier onset of the Neolithic Revolution is indeed positively and significantly correlated with the level of technological sophistication in non-agricultural sectors of the economy in the years CE and 1 CE.
Specifically, in a world with perfect labor mobility, regions with higher aggregate productivity would have experienced labor inflows until regional wage rates were equalized, implying that technology should be positively associated with population density but should not be correlated with income per capita.
The Malthusian theory, inspired by Thomas R. Specifically, the level regression results may be explained by the following non-Malthusian theory. This section establishes 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 CE. The effects of these explanatory channels on income per capita in the corresponding periods, however, are not ghe different from zero, a result that fully complies with Malthusian priors.
Finally, turning attention to the differences in coefficient estimates obtained for the three periods, it is interesting to note that, while the positive effect of land productivity on population density remains rather stable, that of the number of dynqmics elapsed since the onset of agriculture declines over staagnation. To summarize the main findings of the analysis thus far, the results indicate that more productive societies sustained higher population densities, as opposed to higher standards of living, during the time period 1— CE.
Similarly, in the income per capita data-restricted samples employed in Section 4.
The lower carrying capacities of these environments would, in turn, imply lower levels of human population density. From Stagnation to Growth: The Conditions of Agricultural Growth: In addition, the strength and credibility of the numbers of domesticable plant and animal species as instruments continue to be supported by their explanatory power in the first-stage regressions and by the results of the overidentifying restrictions tests.
Table 9 reveals the results of this analysis where, as in Table 7the measure of technology employed is the overall index that incorporates information on the prevalence of sedentary agriculture along with malthusjan level of advancement in non-agricultural technologies. These variables are constructed by the authors based on information reported by the CIA in The World Factbook online resource.
Population, Technology, and Growth: Thus, the error terms in equations 17 and 18 represent the changes over time in the aforementioned country-year-specific disturbance terms, i.
The Galor-Weil Model Revisited: Specifically, although reverse causality is not a source of concern, given that the vast majority of countries underwent the Neolithic transition prior to the Common Era, the OLS estimates of the effect of the time elapsed since the transition to agriculture may suffer from omitted variable bias, reflecting spurious correlations with the outcome variable being examined.
Olsson Ola, Hibbs Douglas A. The IV regressions in Column 6, however, once again reflect the pattern that the causal effect of transition timing on population density in each period is stronger than its corresponding reduced-form effect, while the effect of land productivity remains rather stable across the OLS and IV specifications.
PrescottRobert E. The Physiological Foundations of the Wealth of Nations. The regressions in Table 7 therefore omit the timing of the Neolithic Revolution as an explanatory variable for both population density and income per capita in the two periods examined.
However, unlike the overall index, the non-agricultural counterpart incorporates data on the sector-specific technology indices for only the communications, industrial i. Hence, individuals will be able to afford more children. Thus, the analysis adopts an instrumental variables strategy, exploiting variation in the numbers of prehistoric domesticable species of plants and animals that were native to a region prior to the onset of sedentary agricultural practices as exogenous sources of variation for the number of years elapsed since the Neolithic Revolution to demonstrate its causal effect on population density in the Common Era.
Periods marked by the absence of changes in the level of technology or in the availability of land, were characterized by a stable population size as well as a constant income per capita, whereas periods characterized by improvements in the technological environment or in the availability of land generated only temporary gains in income per capita, eventually leading to a larger but not richer population.
Insights from Unified Growth Theory.
The effect of anv land-productivity channel, controlling for absolute latitude and continental fixed effects, is reported in Column 2. Thus, for a given year, the x- and y-axes plot the residuals obtained from regressing the technology index and population density, ,althusian, for that year on the aforementioned set of covariates. Given that historical population estimates are also available from Maddisonalbeit for a smaller set of countries than McEvedy and JonesTable D.
Across countries, those characterized by superior land productivity or a superior level of technology would have, all else equal, higher population densities in the long run, but their standards of living would not reflect the degree of their technological advancement.
For the CE analysis, the additional sampling bias introduced on OLS estimates by moving to the IV-restricted subsample in Column 5 is similar to that observed earlier in Table 2whereas the bias appears somewhat larger for the analysis in 1 CE.
Finally, in order to ensure that the results from the level regressions are not driven by unobserved time-invariant country fixed effects, this research also employs a first-difference estimation strategy with a lagged explanatory variable.
To account for the technology-diffusion channel, the current analysis employs as a control variable the great-circle distance from the capital city of a country to the closest of eight worldwide regional technological frontiers. Specifically, the relationship reported by Putterman disappears i.