Empirical likelihood confidence intervals for the mean of a population containing many zero values

If a population contains many zero values and the sample size is not very large, the traditional normal approximation‐based confidence intervals for the population mean may have poor coverage probabilities. This problem is substantially reduced by constructing parametric likelihood ratio intervals when an appropriate mixture model can be found. In the context of survey sampling, however, there is a general preference for making minimal assumptions about the population under study. The authors have therefore investigated the coverage properties of nonparametric empirical likelihood confidence intervals for the population mean. They show that under a variety of hypothetical populations, these intervals often outperformed parametric likelihood intervals by having more balanced coverage rates and larger lower bounds. The authors illustrate their methodology using data from the Canadian Labour Force Survey for the year 2000.     

数学教学中渗透创造性思维训练的尝试

通过对联想思维、求异思维、逆向思维、求通求变思维训练的分析,阐述了培养创造性思维的具体方法.     

从交流和传播的视角解读越文化

本组讨论以越文化研究为例,探索地域文化研究的方法与视角。朱文斌一文检讨了当前越文化研究范式的局限,提出了范式转换的问题;陈越、梁涌两文分别从空间与时间的存在与发展上对越文化作了动态描述。其中,陈文从文化模式的角度,把越文化概括为“剑—书”文化;梁文则从交流与传播的角度,揭示了越文化的形成与发展。     

心中的牵挂

午后,沿着熟悉的小路,我慢慢走着。走进了这座城镇,便走进了我心中的牵挂……路两旁仍然是那一排排高高的梧桐树,树干那么直,那么粗,树冠那么大,它的叶子像一个个大手掌,它的果实像一粒粒小青豆。在夏季,梧桐树枝繁叶茂,张开着“大手掌”为我遮挡炎炎烈日。我喜欢行走在这些树荫里,微笑着看人们安静或嘈杂地从我身边走过。有如轻风吹过时,心神一爽。现在,两旁的梧桐树叶已变黄,秋天即至。眼前景色一片灿然。阳光从树中透出,细细碎碎的洒满一路,晃着人的眼睛。很美,但无可奈何地透着说不出的凄凉。一阵风吹过,凉凉地夹杂着几片梧桐树叶,…     

International Tax Competition: A Case for International Cooperation in Globalization

The liberalization of international financial flows and foreign direct investment has induced countries to use diverse measures to attract inflow of foreign capital and foreign direct investment, which is expected to have a positive effect on the growth of GDP and thus a positive effect on social welfare. Tax exemption, reduction of tax rate, tax holiday, or diverse subsidies are some of the most important measures used. In this paper we study international tax cooperation, i.e., countries change and especially reduce tax rate for corporate income or for asset revenues to attract inflow of foreign direct investment. Both theoretical and empirical studies have shown the sensibility of foreign direct investment decision with respect to tax rate differences between home countries and host countries. In general, more inflow of foreign direct investment can be expected if the tax rate of the home country is lower than that of foreign countries. This is the main reason for international tax cooperation. In this paper we propose a simple model to prove the sub-optimal Nash non cooperative solution in a two-country tax-competition game. The model shows that international tax cooperation can improve welfare of the participating countries. How to reach a cooperative solution for an international tax competition game (ITCG) is therefore an important issue for further discussions and studies. International institutions can play a crucial role to reach international tax cooperation or international tax harmonization.     

Block external bootstrap in partially linear models with nonstationary strong mixing error terms

The authors extend the block external bootstrap to partially linear regression models with strongly mixing, nonstationary error terms. In addition to providing an approximate distribution for the semiparametric least square estimator of the parametric component, they propose a consistent estimator of the co‐variance matrix of this estimator.     

伊拉克战争后的中东战略格局

美国发动的伊拉克战争是美国试图建立美国控制下的单极世界的第一场战争．美国在取得战争的胜利后，将在中东建立美国主导下的中东格局，并加紧实施其全球战略．中东政治力量在战后纷纷重组，尤以伊朗的海湾安全战略和以色列的中东超级大国地位确立最为典型。美国主导下的中东虽不会发生大的战争，但中东依旧是动荡之源，未来走势充满变数．     

Demographic crisis: The impact of the Bangladesh civil war (1971) on births and deaths in a rural area of Bangladesh

Summary In Matlab Bazaar Thana the Cholera Research Laboratory has registered the births, deaths and migrations in a population of approximately 125,000 since 1966. Although this rural area was not the scene of any significant armed encounters, striking changes in birth and death rates were registered during and after the conflict. Birth rates did not change during the relatively brief period of the civil war, but a small decline was registered for one year after the war. Fertility rates which had been declining slightly and irregularly in the pre-war baseline period may have increased slightly during the war and fell substantially in all age groups in the year following the war. The crude death rate, which rose by 37 per cent during the war, was a very sensitive reflection of the administrative and economic problems. Overall infant mortality rose by only 15 per cent over pre-war levels because all of the increase was observed in the post-neo-natal component, which traditionally accounts for less than one-third of the total infant mortality in Bangladesh. Children and older adults accounted for the majority of excess deaths which were largely attributed to acute diarrhoeas and other gastro-intestinal causes. The death rate at ages 1-4 rose by 43 per cent and at ages 5-9 soared to 208 per cent above pre-war baseline rates. All increases in age-specific mortality rates fell to baseline levels during the year following the war, except the 5-9-year age group, in which rates continued to be high largely because of deaths due to dysentery.