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71.
72.
Abstract. In this paper, we extend the partial equilibrium urban model of DeSalvo (1985) to include mode choice. DeSalvo demonstrated that the urban model of Muth (1969) was robust to the extension to leisure choice. We show that the model is robust to mode choice as well. In addition, we derive the comparative static results that commuters choose higher speed modes for longer commutes, at higher wage rates, with greater tastes for housing, and with lower housing prices. Also, for a given distance commuted, we derive the comparative static result that commuters chose shorter duration commutes at higher wage rates. Whereas it is typically assumed that marginal commuting cost is positive and non‐increasing with distance, we derive these results. Moreover, we derive the results that marginal commuting cost rises with an exogenous increase in housing price and falls with increased tastes for housing. We also explore the effects of exogenous commuting‐cost changes on the endogenous variables of the model. The remaining comparative static results on housing consumption and location are qualitatively the same as in DeSalvo.  相似文献   
73.
Whose Burden?     
Book reviewed in this article:
Allan Megill, Karl Marx: The Burden of Reason (Why Marx Rejected Politics and The Market)  相似文献   
74.
Although sickle blades gloss is known to form during the harvest, which is a dynamic process and although it is known to be a type of wear which is the outcome of the repetitive encounters between the sickle blades working edges and plant stems; there is no common way to quantify its intensity. Since there is no consensus over a specific scale that will enable the estimation of the amount of wear, based on the quantification of gloss brightness intensity. In this paper we propose a new measurement system which is based on the projection of laser (He–Ne) beam on glossed sickle blades and an analysis of the reflected images. The results form a relative scale from which it is possible to infer on the sickle blades level of wear, and to create discard models.  相似文献   
75.
The role of raw material quality in Oldowan technology has not been fully explored. There are numerous studies suggesting Oldowan hominins preferred certain types of stone for artifact manufacture. Previous studies of the artifact assemblage from the early Pliocene Oldowan locality of Kanjera South (South Rachuonyo District, Kenya) show that raw material selection and transport was an important aspect of Late Pliocene hominin adaptations. Yet the exact properties of stones that hominins were selecting remain enigmatic. Two potentially important features of artifact raw material are durability and fracture predictability. We investigate fracture predictability through mechanical tests of stone and investigations of the affect of stone properties on fracture patterns in archaeological collections. We investigate stone durability with actualistic studies of edge attrition combined with further mechanical tests of various lithologies. Oldowan hominins at Kanjera appear to have selected raw materials based on their durability. The ability for a stone to fracture consistently does not appear to be as important in hominin toolstone preference as previously assumed. Hominins that produced the assemblages at Kanjera South appear to have incorporated an extensive understanding of various attributes of raw material in the transport and production of stone artifacts. When combined with previous research on the transport patterns at Kanjera, the results of this study provide evidence for a more complex raw material acquisition strategy than has previously been suggested for Late Pliocene Oldowan hominins.  相似文献   
76.
Among peace researchers and practitioners, it is generally accepted that efforts to prevent violence can be instrumental in its mitigation. So, it was distressing to read the research findings of Meier, Bond, and Bond (2007) that mitigation was positively related to organized raids in the Horn of Africa where there is pastoralist–pastoralist and pastoralist–agriculturalist violence. This article seeks to build on their research. It uses a ‘de-trending’ approach for time-series analysis that is commonly used in economics and financial studies. It reports an opposite statistically significant finding. When the data used by Meier et al. are de-trended, violence associated with organized raids is negatively correlated with mitigation. This negative correlation is similar when data on mitigation and organized raids are de-trended with time as a predictor, on the one hand, and with seasonality over time as a predictor, on the other. Implications regarding the temporal dimension of peace research and practice are presented.  相似文献   
77.
78.
ABSTRACT On a sample of U.S. urbanized areas in 2000, we test theoretical hypotheses of the effect of land‐use controls on the spatial size of urban areas. We find that minimum lot‐size zoning and maximum FAR restrictions expand the urban area, while maximum lot‐size zoning, urban growth boundaries, minimum square footage limits, maximum building permit restrictions, minimum person per room controls, and impact fees contract the urban area. All of these findings are consistent with theoretical predictions although the effect of urban growth boundaries and minimum square footage limits are not statistically significant.  相似文献   
79.
Despite rapid economic growth and massive inflows of aid, rural poverty in Mozambique is worsening. Agricultural production and productivity have not increased in the last decade. Use of chemical fertilizers and other modern technology is at a low level and decreasing. The present development model emphasizes that the role of government and donors is to provide human capital and infrastructure, while the private sector is responsible for economic development and ending poverty. The most recent national surveys confirm what is being seen elsewhere in Africa — that this non‐interventionist strategy does not raise agricultural productivity or reduce poverty. While 80 per cent of Mozambique's population is engaged in agriculture, this sector contributes only 20 per cent of GDP. This suggests that investments in agriculture are likely to generate pro‐poor growth, both to rural and urban dwellers. This policy failure is increasingly recognized, but donors and government have invested too much political capital in the current policy to change easily.  相似文献   
80.
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