The small but important region of Dahomey (now the People's Republic of Benin) has played an active role in the world economy throughout the era of mercantile and industrial capitalism, beginning as an exporter of slaves and becoming an exporter of plain oil and palm kernels. This book covers a span of three centuries, integrating into a single framework the pre-colonial, colonial and post-colonial economic history of Dahomey. Mr Manning has pieced together an extensive body of new evidence and new interpretations: he has combined descriptive evidence with quantitative data on foreign trade, slave demography and colonial government finance, and has used both Marxian and Neoclassical techniques of economic analysis. He argues that, despite the severe strain on population and economic growth caused by the slave trade, the economy continued to expand from the seventeenth to the nineteenth century, and the colonial state acted as an economic depressant rather than a stimulant.

Maize (Zea mays L.) production in the Midsouthern USA has increased dramatically in recent years, primarily as a function of growing nematode pressure in cotton (Gossypium hirsutum L.) and soybean [Glycine max (L.) Merr.] fields as well as the increasing yield potential of maize hybrids. Traditionally, 112-to 120-d maturity hybrids (full season) have been grown using 76-cm row spacing at population densities of »6 to 8 plants m 22 . These hybrids, however, reach the reproductive phase of development during the period of a typical midseason drought. Shorterseason (,110-d maturity) hybrids, by contrast, avoid a large portion of this drought and require substantially less irrigation. The yield potentials of short-season hybrids are similar to those of full-season hybrids, but they require substantially narrower rows (50 cm) and increased populations (10 to 12 plants m 22 ). In this report, economic trade-offs among irrigation, seeding rates, yield potential, and seasonal market price trends for production of short-season hybrids are evaluated. Shorter-season hybrids were comparable to longer-season hybrids in terms of yield potential and partial returns. In general, profit-maximizing seeding rates were higher for shorter-season hybrids, and higher seasonal prices were insufficient to offset higher seeding costs and thereby change optimal hybrid choice. While irrigation use was curtailed with shorter-season hybrids, irrigation savings, at current irrigation costs, were insufficient to offset higher seeding costs. Finally, using a simple decision rule of picking maize hybrid by selecting top-yielding hybrids is challenged in this study as lower-yielding hybrids with lower seeding requirements exhibited higher comparative returns than the highestyielding hybrids at one of the locations.

With increased emphasis on risk management in agriculture and a lack of disaggregated or farm-level yield time series, decision makers are often faced with having to make adjustments to temporal yield risk measures obtained from readily available but aggregated yield data. This paper provides some empirical evidence on what type of aggregation bias to expect when measuring temporal yield risk using yield observations averaged across a region relative to yield risk estimated from quarter-section yield time series in wheat. This study highlights some of the challenges faced when estimating aggregation distortions in measuring yield risk defined by temporal variance, especially given the nature of the empirical data set used. Cluster analysis, visual examination of relative frequency distributions and mapping of yield risk clusters suggest that using a readily available, aggregate temporal yield risk measure has the tendency to underestimate yield risk observed at the quarter-section level and that clear, geographic yield risk boundaries do not exist in municipalities or across larger areas in this study. Further research on crops more risky than wheat appears promising.Avec un plus grand inte'ret sur la gestion du risk dans 1 'agriculture et un manque de donne'es de'taillees OM bien de collections de se'ries temporelles sur les rendements, les de'cideurs sont souvent tenus d'apporter des correct$ aux measures du risk obtenues a partir des donne'es de rendements qui sont disponibles. Cet artcle apporte une preuve empirique du type de biais lie a l'agre'gation qui peut &re prsent dans le calcul du risk de rendement temporel obtenu a partir de rendements moyens de ble' observis au niveau regional en comparaison du risk de rendement qui est estime' a partir de donnies base'es sur des quart-de-sections.Cette e'tude met en exergue quelques uns des obstacles qui se pre'sentent dans l'estimation de distosions lie'es a 1 'aggre'gation dans le calcul du risk de rendement ddfini par la variance temporelle, speciallement itant donne la charactkre empirique des donne'es utiliskes. L'analyse de groupe, l'examen visual de la distribution des fre'quences relatives, et la cartographie de classes de risk de rendement sugg2rent que l'utilisation de la measure du risk de rendement base'e sur des donne'es disponibles de risk aggr2ge temporel a tendence a sousestimer le risk de rendement observe au niveau des quart-desections et qu'il n'y a pas de fronti2res de risk de rendement certaines, ge'ographiques qui existent entre les municipalite's OM bien a travers les zones plus larges examine'es dans cette etude.

This article analyses the patterns and dynamics of the global social insurance movement since the 1880s through the framework of 'interactive diffusion'. It argues that two principal models of social insurance -the German capitalist and Soviet socialist -diffused around the world throughout the twentieth century. It contends that global forces conveyed basic ideas while national forces determined the timing and specifics of the adoption of global models. From the 1980s, however, a new global model of privatization emerged with the rise of neo-liberalism and support from the World Bank. Privatization partially replaced public pension systems in Latin America, then in the former socialist countries in Europe and in a few other countries. Nevertheless, national compulsory social insurance has remained the predominant form for social protection in the world. ÃThe authors wish to extend their warmest thanks to Adam McKeown for his insightful comments on earlier versions of this article.

"A researcher interested in crop yield risk analysis often has to contend with a lack of field- or farm-level data. While spatially aggregated yield data are often readily available from various agencies, aggregation distortions for farm-level analysis may exist. This paper addresses how much aggregation distortion might be expected and whether findings are robust across wheat, canola and flax grown in two central Canadian production regions, differing mainly by rainfall, frost-free growing days and soil type. Using Manitoba Crop Insurance Corporation data from 1980 to 1990, this research, regardless of crop or region analyzed, indicates that (i) spatial patterns in risk are absent; (ii) use of aggregate data overwhelmingly under-estimates field-level yield risk; and (iii) use of a relative risk measure compared to an absolute risk measure leads to slightly less aggregation distortion. Analysts interested in conducting farm-level analysis using aggregate data are offered a range of adjustment factors to adjust for potential bias." Copyright 2005 Canadian Agricultural Economics Society.

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soil. Planting of the crop over this low density slot is critical. These soils occur in the USA, primarily in the Using deep tillage to alleviate the adverse effects of deleterious soil Coastal Plains, and in other regions to a minor extent physical properties has been tried many times. Consistent economic returns have been reported for in-the-row subsoiling of loamy sand (Buol, 1973). and coarser soils and for deep loamy soils where the subsoil slit bisectsIn the Mississippi River alluvium region, for example, the water flow channel during rainfall events where there is runoff. yield responses to deep tillage were found for cotton Recent reports of yield responses on clayey soils and silt loams led to (Gossypium hirsutum L.) on deep silt loam or sandy a reassessment of subsoiling of these soils in Arkansas. A randomized loam soils (Spurgeon et al., 1978; Tupper and Spurgeon, complete block design was conducted at four locations with tillage 1981). This response differed from that of nonplastic treatments of conventional shallow, deep chisel, subsoil dry, subsoil soils in that no response was obtained from in-the-row wet, subsoil at 45؇ to planting direction, and paratill. Plots were harsubsoiling. The best results were obtained from deep vested for grain. Economic analysis was performed using the Missistillage in the fall, which left low-density slits that geometsippi State Budget Generator (MSBG). The machinery complement was commensurate with that found on farms in the region. Net returns rically intersected the low points between old seedling above total specified costs (NRAT) rather than above direct costs rows. The low points concentrate runoff water during were calculated to reflect the decision framework of a producer. A high intensity rainfall events. Thus, it appears that deep profitable yield response was obtained from subsoiling in dry soil on tillage here was promoting infiltration and subsequent deep alluvial clayey and silt loam soils but not on the thin loessial soil water storage in these deep silt or sandy loam soils. silt loams. Net returns to subsoiling wet were not significantly higher More recent studies (Keisling et al., 1998) using a paratill than those to conventional shallow tillage. Tillage with a chisel plow on a bedded system tended to provide consistently as deep as it could be operated (approximately 15 cm) was not a higher cotton yields than conventional tillage practices. substitute for subsoiling because yield responses from deeper tillage were not comparable. The 45؇ subsoiling in dry soil tended to be No consistent soybean [Glycine max (L.) Merr.] or superior to all other tillage treatments.

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