Modeling Conditional Yield Densities

Given the increasing interest in agricultural risk, many have sought improved methods to characterize conditional crop-yield densities. While most have postulated the Beta as a flexible alternative to the Normal, others have chosen nonparametric methods. Unfortunately, yield data tends not to be sufficiently abundant to invalidate many reasonable parametric models. This is problematic because conclusions from economic analyses, which require estimated conditional yield densities, tend not to be invariant to the modeling assumption. We propose a semiparametric estimator that, because of its theoretical properties and our simulation results, enables one to empirically proceed with a higher degree of confidence.     

Stochastic Technology, Risk Preferences, and Adoption of Site-Specific Technologies

A model of farmer decision making is developed to determine the extent to which uncertainties about soil fertility and weather affect the value of site-specific technologies (SSTs) using jointly estimated risk and technology parameters. Uncertainty can lead risk-averse farmers to apply more fertilizers and generate more pollution than in the certainty case. Ignoring uncertainty and risk aversion would overestimate the economic and environmental benefits of SSTs and underestimate the subsidy required to induce adoption. Accounting for uncertainties and risk preferences might explain the low observed adoption rates of SSTs. Improving the accuracy of SSTs would increase the incentives for adoption.     

对《形状和位置公差》新标准的理解和应用

通过对《形状和位置公差》新、旧国际的对比，综述了新、旧标准间的不同之处、便于迅速了解和应用新标准。     

Price rigidities and institutional variations in markets with posted prices

Summary Standard laboratory posted-offer markets respond slowly and incompletely to demand shocks. In these one-sided markets, where sellers control the setting of prices, very little information is transmitted via the process of exchange. For this reason, traders have trouble distinguishing randomness in their own experience from changes in market fundamentals. This paper reports the results of twelve laboratory markets conducted to assess whether some common variants to standard posted-offer rules can correct the adjustment deficiences. Although discounting, multiple postings and excess demand information all improve performance, we find that response remains poor, and efficiencies low.Support for this research was provided by the National Science Foundation (SBR 9319842 and SBR 9320044), and the University of Virginia Bankard Fund. Data are archived at FTP address: fido.econlab.arizona.edu. We wish to thank Charles Plott and Shyam Sunder for useful comments on an earlier draft of this paper. The usual disclaimer applies.     

论军服式样对服装文化的影响

该文认为．在人类服饰文化的悠久历史中．不同时期各领风骚的流行服装式样或多或少地都受到了军队服装的影响．军队服装已经渗入到人类服饰文化的方方面面．对推动服饰变革起着重要的作用．     

China’s Labor Market on Crossroad

I.IntroductionSincethelate1990s,China’slabor market has comeundergreat pressure,asreflected by anincreasing unemployment rate,and adeclining labor force participation rate.The causesofthe severe unemployment are threefold.First,due to the macro-economic downturn andrapid industrial structural change in the late1990s,state-owned enterprises(SOEs),whichlost their comparative advantage and competitiveness,have been unable to fully utilizetheir production capacity,and have become loss-makers.Se…     

Adjustment, Stabilisation and the Analysis of the Employment Structure in Turkey: An Input- Output Approach

The aim of the paper is to examine the effects on employment of the large-scale structural adjustment programme undertaken by Turkey from the early 1980s onwards. In this respect, we particularly analyse how appropriate the choices of factor intensity after structural adjustment programme have been in the domestic production in comparison with the availability of domestic factor endowment. Our findings show that foreign trade in intermediate goods creates extra use of domestic labour, which can be considered as the labour cost of importing intermediate goods. This is the case in the majority of industries in the pre- and post-liberalisation period in Turkey. However, the capacity of using extra labour as a result of importing intermediate goods appeared to have decreased in the post-liberalisation period.     

基于SyncML协议的移动数据库同步冲突处理策略

在移动数据库中,通过同步处理保证了数据的一致性。文章针对移动数据库的断接性、资源有限性等特点,在分析SyncML协议的同步框架基础上,提出一种基于SyncML协议的冲突检测及处理方法,并进行深入研究和实现,进一步完善了基于SyncML协议的移动数据库同步功能。