Empirical findings on socioeconomic determinants of fertility differentials in Costa Rica

"This paper seeks to (1) identify socioeconomic variables that are expected to generate fertility differentials; (2) hypothesize the direction and magnitude of the effect of each variable by reference to a demand-for-children model; and (3) test empirically the model using evidence from Costa Rica. The estimates are obtained from a ten-percent systematic random sample of all Costa Rican individual-family households. There are 15,924 families in the sample...." The authors specifically seek "to capture the effects of changing relative prices and available income and time constraints on parental preferences for children. Least-squares estimates show statistically significant relationships between household fertility and opportunity cost of time, parental education, occurrence of an extended family, medical care, household sanitation, economic sector of employment, and household stock of nonhuman capital."     

The labour market experiences of Canadian immigrants

The economic adaptation of immigrants to Canada is analyzed using government data on the labor force and landed immigrants. In particular, the labor force experience of a sample of immigrants in Canada is examined and compared with that of a Canadian cohort with regard to length of unemployment and income. "Differences in unemployment and insurable earnings are examined by age, sex, immigrant category..., world area of last permanent residence, official language abilities, education, and region of residence." (summary in FRE, SPA)     

Individual behavior under risk and under uncertainty: An experimental study

These experiments are concerned with individual behavior under risk and under uncertainty. By exploiting the isolation effect the experiments were able to offer to 134 subjects the possibility of actually gaining or losing an important sum of money.The experimental data show that under risk as well as under complete ignorance the subjects' attitudes towards prospects of gains and towards prospects of losses are totally unrelated.The data also show that when facing prospects of gains, the subjects generally take the exact probabilities of the events into account, whereas, when facing prospects of losses many of then have only recourse to coarser categories of plausibility, or even no longer use their information at all.     

THE PERSISTENCE OF POLITICAL ATTITUDES AMONG 1960s CIVIL RIGHTS ACTIVISTS

A scattering of recent research has studied the current politicalbeliefs and attitudes of individuals identified as "1960s activists."In contrast to much of the treatment accorded such people inthe popular media, this research tends to find most of theseactivists currently liberal on a wide variety of political topics.However, in the absence of panel data, most of this researchhas had to assess any change in the activists' attitudes eitherby assuming the activists' past positions or by trusting totheir retrospective reports. In this paper we report on panel data from a large group ofwhite activists, mostly students, who spent the summer of 1965organizing voter registration drives in Southern black communities.In some specific areas on which the activists tended to holdrather extreme positions in 1965, they may have moderated by1984. However, their overall pattern of response on a wide varietyof issues is basically stable over this twenty-year period.     

The employment effects of immigration: a balance sheet approach

The impact of immigration on unemployment in Canada is examined for the period 1983-1985. The authors attempt to construct a balance sheet of immigration in terms of labor supply and demand. They conclude that immigrants create more jobs than they fill, and that their net effect on the employment situation is positive. (SUMMARY IN FRE AND SPA)     

New sources on the demographic history of the Southern Andes (sixteenth to eighteenth centuries)

The author describes and evaluates some little-known sources of data on the Southern Andes for the period from the sixteenth to the eighteenth century.     

基于交通量风险的PPP交通项目再融资产品设计

交通PPP项目的投资大、风险高。政府作为发起方,需要为项目提供担保以吸引社会资本方的参与,但过度依赖政府担保意味着：一旦发生数额较大的债务违约将会给财政造成巨大的负担,因此有必要谋求适宜的市场化融资渠道。为了协调PPP项目相关者的利益,本文在项目收益债的基础上嵌入了与项目未来收益挂钩的或有条款,并运用结构化方法中的Merton模型在风险中性情景下对融资产品进行了定价。最后,以某PPP交通项目为例,进行了具体的融资产品设计,计算了相应的产品价格和风险价差,并对某些关键条款进行了敏感性分析,结果表明该产品能够在有效减轻政府担保的基础上降低融资成本。     

The new treatment mode research of hepatitis B based on ant colony algorithm

Hepatitis B (HB) is a deadly disease that has a severe impact on infected individuals. In China, not only are the incidence and infection rates of HB very high, but also many HB patients suffer from mental illness associated with anxiety and fear because of HB-associated symptoms. This exacerbates the patients’ condition, potentially increasing the risk of mortality. In this paper, we propose a new treatment mode to improve the therapeutic efficiency and patients’ satisfaction with their healthcare. In a single process of this new treatment, several patients with similar disease symptoms are treated by one doctor at the same time. This new treatment mode can not only relieve the anxiety and fear of HB patients, and improve patients’ cognition rate of HB, but also reduce the HB infection rate, slow down the progression of disease symptoms, and shorten the course. If patients with similar disease symptoms are to be grouped together, there is a need to determine the optimal patient batch combination, which can be solved in the new mode, called patient combined problem (PCP). We also constructed a mathematical model of PCP, and present the ant colony (AC) algorithm and Enhanced AC with a P-3-exchange operator for PCP in the new treatment mode in this paper. We also performed an experiment that showed that our proposed algorithms are very fast and effective for solving this problem.

     

我国各民族交往交流交融的空间生产与实践路径

各民族交往交流交融是铸牢中华民族共同体意识的路径选择。民族社会结构的存在和发展为各民族交往交流交融提供了可实现的行动空间及空间生产基础,运用空间生产理论对民族交往交流交融的空间生产与空间结构进行分析,即各民族交往的物质空间生产是基于共同利益与互惠发展的经济交往、各民族交流的符号空间生产是注重共有价值和情感寄托的文化交流、各民族交融的精神空间生产是强调生活互嵌和共生体验的精神交融。基于此,加强各民族交往交流交融的实践路径应是推动民族地区经济交往,构建以平衡互惠为原则的多民族经济圈;促进民族乡土文化交流,发展以情感共鸣为重心的乡村文化中心;深化各族群众生活交融,规划以结构互嵌为内核的社区公共空间。通过上述路径,达成铸牢中华民族共同体意识的根本目标。