A play-the-winner-type urn design with reduced variability

We propose a new adaptive allocation rule, the drop-the-loser, that randomizes subjects in the course of a trial comparing treatments with dichotomous outcomes. The rule tends to assign more patients to better treatments with the same limiting proportion as the randomized play-the-winner rule. The new design has significantly less variable allocation proportion than the randomized play-the-winner rule. Decrease in variability translates into a gain in statistical power. For some values of success probabilities the drop-the-loser rule has a double advantage over conventional equal allocation in that it has better power and assigns more subjects to the better treatment. Acknowledgments. I thank Stephen Durham, the associate editor, and the referees for their helpful suggestions.     

The costs of non-tariff barriers to trade: Evidence from New Zealand

The Costs of Non-Tariff Barriers to Trade: Evidence from New Zealand. — Recent work on trade policy with imperfect competition indicates that the adverse effects of non-tariff barriers to trade exceed those suggested by traditional theory. With market power in foreign supply, setting a restrictive non-tariff barrier will induce foreign exporters to raise their supply prices. The authors use the experiment provided by the comprehensive New Zealand economic reforms of the mid-1980s. Using panel data on export unit values from Germany and the United States to several destinations including New Zealand, they find some evidence for decreased export prices to New Zealand as a result of the dismantling of non-tariff barriers to trade.     

高校女生体育课堂教学的现状及对策

调查发现女生中只有33．97％对体育课有兴趣，原因是：体育意识不成熟、教材存在重复现象、有严重的心理障碍、没有突破传统的教学方法、课外活动缺乏行之有效的组织管理等。应采取的措施有：明确高校体育教育理念、加强思想教育、改革体育教学模式、合理选择教学内容和方法等。     

Risk preferences in multi-period consumption models, the equity premium puzzle, and habit formation utility

The relationship between the relative risk aversion measure for the utility function for consumption and that for the value function for wealth is a derived relationship whose properties depend on how consumption and wealth are defined and measured. This fact together with information concerning estimates for these two relative risk aversion measures is used to give another perspective on the equity premium puzzle, and to explain why it is that the habit formation utility function is effective in eliminating that puzzle. A time separable utility function that can serve as an alternative to the assumption of habit formation is also presented.     

Income and substitution effects of fiscal policy on work effort

The focus of this paper is twofold. First, it examines the impact on work effort of changes in government purchases financed with lump‐sum taxes, in a neoclassical framework, with respect to four industrialised countries. Second, it reconsiders the expenditure–work effort relationship in a broader conceptual context that allows for distortionary taxation and a disaggregation of the income and substitution effects. Our findings are shown to cast doubt on the empirical plausibility of the prevailing (neoclassical and New Keynesian) models which seem to rely heavily on the lump‐sum tax notion, thus ignoring the substitution effects of distortionary taxation.     

Competitive equilibria with limited enforcement

We show how to decentralize constrained efficient allocations that arise from enforcement constraints between sovereign nations. In a pure exchange economy these allocations can be decentralized with private agents acting competitively and taking as given government default decisions on foreign debt. In an economy with capital these allocations can be decentralized if the government can tax capital income as well as default on foreign debt. The tax on capital income is needed to make private agents internalize a subtle externality. The decisions of the government can arise as an equilibrium of a dynamic game between governments.     

Allocating an advertising budget to international travel markets

Deciding on advertising appropriations is a common problem to all National Tourist Offices. The Austrian National Tourist Office now employs a decision support model allowing for inclusion of managerial judgments. In tourism, like elsewhere, application of standard optimization routines to marketing decision making is straight- forward, once the relationship linking market response to input has been modeled adequately. A tailor-made decision calculus procedure eliciting managerial judgments on the relative importance of the factors determining a receiving country's travel market share provides the weights otherwise inaccessible by objective parameter estimation. A tourism manager thus can evaluate countries as tourism generators and allocate an advertising budget accordingly.     

Cities under stress

This paper studies the effect of terrorist attacks on the internal structure of cities. We develop an urban framework with capital structures suitable for the study of this question and analyze the long and short term implications of this type of events. In the long run, the analysis shows that a terrorist attack will affect urban structure only modestly, relative to the potentially large decrease in the level of economic activity in the city. Land rents will not decline at all locations. In the short run, agglomeration forces will amplify the effect of the original destruction and will reduce urban economic activity temporarily.