Biology, Diseases, and Economics: An Epidemiological History of Slavery in the American South

The economic history of antebellum southern slavery has been and is the subject of ongoing debates among scholars. The literature includes assessments about the efficiency of slavery as well as about the adequacy of slave living standards and diets. Yet this literature under appreciates the important biologic and historical role that parasitic diseases played in the history of slavery. Recognizing the role of parasitic diseases calls into question some prevailing interpretations of slavery. Lacking direct evidence on slave diets, scholars turned to anthropometric evidence as proxies for the living standards of slaves, leading to the prevailing view that adult slaves were given adequate sustenance, but slave infants and children were severely malnourished. We argue it was not slave diets, but the combination of the plantation system and diseases that caused abnormally small slave children. The diseases that concern us, primarily hookworm and malaria, affected slaves ('blacks') and free labor ('whites') differently. Many slaves were concentrated on large plantations with infants and younger children crowded into 'nurseries.' This system allowed the maintenance and spread of diseases that adversely affected younger slaves. Southern white children however were less likely to be raised in conditions so conductive to parasitic diseases. The disease ecology of the antebellum South has implications for the prevailing view that slavery was more efficient than free labor. Biologic evidence indicates that people of tropical West African ancestry are more resilient to the effects of hookworm and malaria than European descendents. Thus when whites did contract these diseases, they were more afflicted than blacks. When slaves entered the adult work force they were taken from disease breeding grounds (slave nurseries) and sent into relatively (for blacks) healthy fields, while whites that went into the fields found a disease environment that was typically worse than that of their childhood. If black adults were more productive than were white adults because of a greater resilience to parasitic diseases, then part of any measured difference in productivity between slave and free farms should be attributed to the disease resistance of African descendents, rather than to any inherent efficiencies of slavery.     

The relative efficiency of slave agriculture: a reply

Professors Hofler and Folland have written a very interesting paper, which brings out several interesting ideas and is a contribution to the literature. They argue that their results contradict those of our original paper concerning the relative efficiency of small versus large slave farms. Specifically they find that large slave farms are relatively more efficient. However, they have missed that main point of the original paper which was to compare the relative efficiency of slave and non-slave farms. On this issue, the Holfer and Folland comment provides no additional insight. Thus their paper, while interesting, is not a comment on our original work.     

The legacy of slavery on hate crime in the United States

Does slavery play a role in explaining why some areas are more prone to hate crimes? Using county-level data on slavery in 1860, I find evidence that U.S. counties with a higher share of slaves in the population more than 150 years ago are more likely to observe hate crime incidents today. One percentage point increase in the share of slaves in the population in 1860 is associated with 0.018 more hate crime incidents per 100,000 population directed at blacks today. Additionally, there is evidence that slavery is associated with more hate crime incidents directed towards Jews and LGBT population. This result supports previous studies which find persistence in cultural norms and racial attitudes.     

Determinants of technical efficiency of crop and livestock farms in Poland

Poland, one of the candidate countries for European Union membership, is currently experiencing acute structural problems within its agriculture sector. This article analyses technical efficiency and its determinants for a panel of individual farms in Poland specialized in crop and livestock production in 2000. Technical efficiency is estimated with stochastic frontier analysis (SFA) and confidence intervals are constructed. Determinants of inefficiency are also evaluated. The SFA results are compared with results using Data Envelopment Analysis (DEA). On average, livestock farms are more technically efficient than crop farms. For both specializations, the size–efficiency relationship is positive, that is large farms are more efficient. The SFA findings are generally supported by the DEA results. Soil quality and the degree of integration with downstream markets are highly important determinants of efficiency. The use of factor markets (land and labour) is important for crop farms, while livestock farms can rely on family labour and own land. Also, education is a constraint to efficiency particularly for crop farms.     

“This One Is 400 Libyan Dinars,This One Is 500”: Insights from Cognitive Human Capital and Slave Trade

One of the most disturbing contemporary episodes in human history that has been decried globally is the recent Libyan experience of slave trade, where migrants captured end-up being sold as slaves. We contribute to the understanding of this phenomenon by investigating the role of cognitive human capital on slave trade. To this end, we use the historic intelligence and slave trade variables, respectively, as the independent and outcome variables of interest. Our findings show a negative relationship between slave trade and cognitive human capital. Hence, the slave trade is more apparent when cognitive human capital is low. The Ordinary Least Squares findings are robust to the control for outliers, uncertainty about the model and Tobit regressions. We substantiate why from the perspective of massive sensitization and education, the non-contemporary relationship between cognitive ability and slave trade established in this study has contemporary practical policy relevance in efforts to stem the tide of clandestine travel to Europe through countries in which clandestine migrants are captured and sold as slaves.     

Droughts,conflict, and the African slave trade

Historians have frequently suggested that droughts helped facilitate the African slave trade. By introducing a previously unused dataset on 19th century rainfall levels in Africa, I provide the first empirical examination of this hypothesis. I find a strong negative relationship between rainfall shocks and the number of slaves exported from a given region. I also find that extreme temperature shocks in either direction increase slave exports. Building on the detailed qualitative work of Dias (1981), Miller (1982), and others, I provide quantitative evidence for interethnic group conflict and more localized forms of violence being likely mechanisms through which these additional slaves were acquired. These results contribute to our understanding of the underlying economic conditions of the African slave trade.     

Measuring technical efficiency in the Greek agricultural sector

This paper measures the degree of technical efficiency of Greek farms at discrete points in time. Stochastic frontier production functions are estimated from four annual Farm Accountancy Data Network (FADN) surveys of the 1992–1995 period. From the results, a measure of technical efficiency is calculated for each farm for each year. The four distributions of technical efficiency values are examined and compared. All four samples show a wide range of farm-specific technical efficiency but efficiency is improving over the period. The paper also presents frontier estimates for small and large farms classified according to economic size. In that case, technical efficiency measures are calculated and their distributions are examined and compared. The results show that large farms are more efficient than small farms. However, efficiency is improving in both size farms over the period. In general, the results of this study indicate that there is substantial scope for improving technical efficiency of Greek farms.     

A comparative study of slave societies

This essay focuses both on theoretical issues and empirical evidence concerning the inevitability of slavery as an economic stage over the course of development. Different types of slavery are described and a number of common hypotheses about the determinants of slave societies and/or slavery are discussed. Several new hypotheses are also proposed which focus upon family and social-structural variables and also upon political factors. The major hypotheses are tested, using a worldwide sample of 60 primitive and peasant societies arranged according to level of economic development. The various older theories are found to explain poorly the presence of slavery while the data give some support to the newly proposed causal relationships.     

Evaluating the technical efficiency of large US law firms

We conduct a performance evaluation in terms of technical efficiency of large law firms based on a unique sample of 163 large law firms in the USA in 1994. To estimate technical efficiency for individual firms, we use the stochastic frontier production function with composed errors where output (measured in terms of revenue) is a function of various labour and human capital inputs. Based on the sample, the average level of technical efficiency in the production of legal service in large US law firms is estimated at 82.20%. More than 87% of the firms attained 75% or higher level of technical efficiency. The estimation results also indicate that the number of lawyers, the number of paralegals, and the number of associates per partner, have a positive and statistically significant effect on the production of legal service.     

Asymmetric Information and Adverse Selection in Mauritian Slave Auctions

Information asymmetry is a necessary prerequisite for testing adverse selection. This paper applies this sequence of tests to Mauritian slave auctions. The theory of dynamic auctions with private and common values suggests that when an informed participant is known to be active, uninformed bidders will be more aggressive and the selling price will be higher. We conjecture that observable family links between buyer and seller entailed superior information and find a strong price premium when a related buyer purchased a slave, indicative of information asymmetry. We then test for adverse selection using sale motivation. Our results indicate large discounts on voluntary as compared to involuntary sales. Consistent with adverse selection, the market anticipated that predominantly low-productivity slaves would be brought to the market in voluntary sales.     

SLAVERY,FREEDOM, AND SEN

Amartya Sen's Development as Freedom argues that the ability to make choices is fundamental to economic development, and that the evaluation of outcomes can provide misleading answers. He uses the example of the high material consumption of US slaves relative to some free whites to illustrate this contrast. This paper discusses some of the implications of such comparisons and the problem of evaluating what might be regarded as favorable outcomes which come from unfavorable institutions (e.g., slavery). It appears that all good things do not necessarily go together. The past relation of enslavement to the need for subsistence is discussed. Differences in gender roles under slavery and after emancipation are also examined.     

The myth of large farm superiority: Lessons from agricultural transition in poland

In Poland, larger farms are often actively promoted over small farms. This policy is based on the perception that there are economies of scale that favor large farms; however, this is contrary to international evidence, which generally indicates that larger farms are less efficient and use less labor than smallscale family farms.

Using both total factor productivity measures and data envelopment analysis, empirical findings from Poland suggest that larger farms are no more efficient than smaller farms, and smaller farms are relatively more labor-intensive. These results have important policy implications for farm restructuring in Poland and other transition economies.     

Economic efficiency and downside risk

This article investigates the impact of downside risk on cost and revenue efficiency (RE) for a sample of farms. Downside risk or loss below a certain level of return is a concern regardless of producer risk preferences and thus a suitable measure of risk to use. Downside risk was measured as the weighted summation of net farm income below the amount needed for unpaid labour during the previous 10 years. Cost and RE were estimated using traditional input and output measures, and then re-estimated including each farm’s downside risk. Comparisons were made between the efficient farms with and without downside risk and the average for all farms. As expected, downside risk plays an important role in explaining farm inefficiency. Failure to account for downside risk overstates inefficiency and can lead to unrealistic expectations in potential efficiency improvements.     

Effects of the Australian New Tax System on Income Tax and Benefits with and without Labour Supply Responses

This article uses the Melbourne Institute Tax and Transfer Simulator to examine the effects of changes to the social security and income tax system as introduced by the Australian New Tax System in July 2000. First this whole set of changes is studied, followed by a separate discussion of some of its components. From the results it is clear that the change in income tax rates and thresholds had the largest effect, because it affected a large proportion of the population whereas the changes to the benefit system were only relevant to smaller groups. Small labour supply responses are predicted to result from the reform, which lower the increase in expenditure (for singles the expectation is that the increase may even turn into a decrease) and lower the decrease in revenue. Overall, the labour supply responses are expected to reduce the cost of the reform.     

Analysis of environmental efficiency variations: A nutrient balance approach

Recent literature has argued that environmental efficiency (EE), which is built on the materials balance (MB) principle, is more suitable than other EE measures in situations where the law of mass conversation regulates production processes. In addition, the MB-based EE method is particularly useful in analysing possible trade-offs between cost and environmental performance. Identifying determinants of MB-based EE can provide useful information to decision makers but there are very few empirical investigations into this issue. This article proposes the use of data envelopment analysis and stochastic frontier analysis techniques to analyse variation in MB-based EE. Specifically, the article develops a stochastic nutrient frontier and nutrient inefficiency model to analyse determinants of MB-based EE. The empirical study applies both techniques to investigate MB-based EE of 96 rice farms in South Korea. The size of land, fertiliser consumption intensity, cost allocative efficiency, and the share of owned land out of total land are found to be correlated with MB-based EE. The results confirm the presence of a trade-off between MB-based EE and cost allocative efficiency and this finding, favouring policy interventions to help farms simultaneously achieve cost efficiency and MP-based EE.     

Task-Based Segmentation of Rural Labour Contracts: Theory and Evidence

The paper examines the theoretical and empirical validity of task-based segmentation of rural labour contracts in seasonal agriculture. Regular labour is hired to perform tasks that are difficult to supervise for which casual labour is not incentive-compatible, and a regular wage above the reservation wage ensures no shirking in these tasks. It is argued that there is a hoarding cost of regular labour which is the cost when productivity is low during the slack season. This implies that minimization of supervision costs necessitates the employment of regular labour in certain tasks, but enhances hoarding cost. Results from the ICRISAT villages in India suggests that daily regular wages are lower than daily casual wages, adjusted by the probability of unemployment. Estimates of a tobit selection model suggest that (a) task characteristics are not significant even among the farms hiring regular labour, (b) larger employment-intensive farms tend to hire more regular labour irrespective of the choice of crop, and (c) there is a significant substitutability between regular and family labour. These results seem to question the very basis of task-based segmentation and strengthen the hoarding cost argument: farms hiring regular labour use it indiscriminately in both non-monitorable and monitorable tasks and, if possible, they may substitute family labour for regular labour with a view to minimizing hoarding cost.     

A limited-dependent analysis of the choice of regular labour contract in seasonal agriculture

The paper examines both theoretically and empirically the factors determining the demand for regular labour in seasonal agriculture. In an implicit contract framework it is argued that there are ‘hoarding costs’ of regular labour in the slack period when there is not much work to be done. Consequently, the number of regular labour employed is constrained by the hoarding cost where larger employment-intensive farms tend to hire more regular labour. Evidence from the ICRISAT villages in India, too, show that though the marginal costs of regular labour are zero, there are significant hoarding costs of regular labour among small farms so that larger farmers are the major demanders of regular labour. Estimates of the double-hurdle model jointly determining the probability of hiring regular labour and demand for regular labour-hours (if a regular labour is hired) are shown to be an improvement over univariate tobit estimates of the demand for regular labour-hours only.     

Factor complementarity and labour market dynamics

We propose and estimate a dynamic stochastic general equilibrium model featuring search and matching frictions, deep habits and a CES production function. The model successfully replicates the cyclical properties of labour market variables in the US economy for three main reasons. First, two of the endogenous mechanisms of the model – factor complementarity and unemployment benefits – play a key role for explaining the amplification in unemployment and vacancies. Second, deep habits have a smaller but significant role as an endogenous mechanism. Third, capital-augmenting productivity, investment-specific and matching efficiency innovations explain large part of the variation in labour market variables.     

规模化养殖对我国肉鸡生产效率的影响——基于随机前沿生产函数的实证分析

采用随机前沿方法,利用2004—2010年我国24个省份的肉鸡生产数据,实证分析了规模化养殖对我国肉鸡生产效率的影响,并对不同养殖规模的肉鸡生产效率进行了测度和比较。结果显示:规模化养殖很大程度上提高了我国肉鸡生产效率,中规模养殖使肉鸡生产效率提高了16.89%,大规模养殖使肉鸡生产效率提高了57.62%;我国肉鸡生产效率的地区差异较大,且南方地区不同养殖规模的肉鸡生产效率存在显著差异,而北方地区的这种差异较小;标准化规模养殖程度不高是南方地区的肉鸡生产效率总体偏低且不同养殖规模的肉鸡生产效率存在较大差异的主要原因。     

The Impact of Climate Change on Agriculture: Findings from Households in Vietnam

This paper examines farm household-level impacts of climate change by examining the relationship between climatic variables and Vietnamese agricultural output. The Ricardian technique is applied with panel data which accounts for both adaptation strategies and household characteristics. This study proposes a two-stage Hsiao model to correct for collinearity between climatic variables and individual effects. The results show that in the dry season, increases in temperatures are beneficial to all farms in the warmer southern regions, while increases in precipitation will damage only irrigated farms in the Central and South regions. The impact of higher temperature in the wet season is similar, except that it will negatively affect net revenue of irrigated farms in the long run. More rainfall in the wet season will increase net revenue in the North region only. Finally, this study combines the estimated results with future climate scenarios to predict how future changes in climate will affect farmers on aggregate.