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71.
Commercial aquaculture in India has come under attack for having caused negative agricultural and environmental impacts. This paper formulates an interactive model of non-renewable and renewable resources to characterize land allocations between aquaculture and agriculture in ecologically and economically sustainable fashion. Through an empirical application, various economic and policy circumstances that affect the optimal land allocation mix are evaluated. The aquaculture industry must address two economic effects: off-site negative effects on renewable food and other coastal resources, and on-site self-pollution of shrimp ponds. Current regulatory and land-use policies are inadequate to address these effects.  相似文献   
72.
英特尔和美光投资50亿美元共建NAND闪存制造合资企业 2005年11月22日,通过与美光科技公司联盟共同投资50亿美元巨资兴建一家新的合资制造公司,英特尔突然高调进入火爆的NAND闪存市场。英特尔公司进入这一市场的时机  相似文献   
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北极冰川融化将使跨北极通航成为可能,运输公司可减少40%的航运距离。马六甲海峡也将不再垄断国际通运。国际经济将进一步融合。  相似文献   
76.
This paper considers a two‐party election with a single‐dimensional policy space. We assume that each voter has a higher probability of observing the position of the party he is affiliated with than the position of the other party, an assumption that is consistent with the National Election Studies (NES) electoral data set. In equilibrium, the two parties locate away from the median, because the voters who dislike a party's platform observe its policy choice with a lower probability, and its own audience like policy choices that cater to its taste. As the asymmetry in voter information or the cost of voting increases, the parties adopt more extreme platforms, while if there are fewer extreme voters the opposite effect occurs. Making voters more symmetrically informed about the two parties' platforms increases the welfare of society, while asymmetric information acquisition by the voters is worse than no information acquisition at all.  相似文献   
77.
On Conditional Density Estimation   总被引:1,自引:0,他引:1  
With the aim of mitigating the possible problem of negativity in the estimation of the conditional density function, we introduce a so-called re-weighted Nadaraya-Watson (RNW) estimator. The proposed RNW estimator is constructed by a slight modification of the well-known Nadaraya-Watson smoother. With a detailed asymptotic analysis, we demonstrate that the RNW smoother preserves the superior large-sample bias property of the local linear smoother of the conditional density recently proposed in the literature. As a matter of independent statistical interest, the limit distribution of the RNW estimator is also derived.  相似文献   
78.
In 1983, the Greater London Council adopted a policy of 'Contract Compliance' designed to ensure that firms selling goods and services to the Council complied with its equal opportunity requirements. The initiative aroused wide interest and many other local authorities - 40 are known of to date - have been considering introducing such a policy. Although simple in essence, its execution can be complex and difficult. In April 1986, the Inner London Education Authority, a partner in the GLC policy, took over the Contract Compliance Unit following the GLCs abolition. Linda Smith explains the background to contract compliance, how the GLC, now ILEA, operates the policy; assesses its achievements and its significance and explores some of the lessons learnt in its three years of operation.  相似文献   
79.
This study analyzes the effects of an important postderegulation innovation on rail freight productivity: the elimination of cabooses and related crew members. It also analyzes the overall growth of productivity in rail freight between 1983 and 1997 (using a translog rail cost function estimated over a sample of Class I railroads between 1983 and 1997). The results indicate that elimination of cabooses and associated crew members from freight trains reduced costs by 5-8% on the typical Class I railroad in 1997, equivalent to an annual cost saving of $2 billion to $3.3 billion for all Class I railroads. Moreover, if Class I railroads had no other technological advances since 1983, their 1997 costs (with 1997 factor prices) would have been 36-43% higher than they in fact were. Finally, the results show that overall productivity growth in rail freight did not decelerate between 1983 and 1997; if anything, it accelerated slightly.  相似文献   
80.
Two of the main forces driving European emigration in the late nineteenth century were real wage gaps between sending and receiving regions and demographic booms in the low‐wage sending regions. Our new estimates of net migration for the countries of sub‐Saharan Africa show that exactly the same forces driving African across‐border migration are at work today. The results suggest that rapid growth in the cohort of potential young emigrants, population pressure on the resource base, and slow economic growth are likely to intensify the pressure for migration out of Africa and into high‐wage OECD countries over the next two decades.  相似文献   
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