Major obstacles to control of irregular migrations: prerequisites to policy

This paper examines 3 basic obstacles thwarting all attempts to reduce irregular migration. The 1st, rather well known and analyzed, underscores the dependency of all regulation of migratory flows on the system of economic and political relations between developed and developing countries. The 2nd obstacle resides in the persistance and growth of subsequent dependent irregular migration. This obstacle also reveals the relative autonomy of population movements compared with the employment situation in the labor market. The 3rd generally ignored obstacle is the role played by migration itself, particularly the discriminatory status of foreign workers in the labor market, in producing irregular migration.     

Perceived morbidity, utilisation of health services and factors affecting it in a rural area

A survey of perceived morbidity was carried out in rural population in eight villages and four wards of Saoner town, covering a total population of 8,876. The nature of illness was assessed by weekly visits to the families. History regarding treatment taken for disease and its source was taken. The overall incidence of perceived morbidity was 176.35 spells of sickness per 1000 population per month. Health care agency was contacted for 36.7 per cent spells of sickness. Utilisation of health services was found to be affected significantly by factors like age (chi 2 = 138.36), literacy (chi 2 = 14.123), type of occupation (chi 2 = 433.74), nature of illness (chi 2 = 83.578) and accessibility of health services. A health behaviour model of the population has also been discussed in this paper.     

On some characteristics of China's population--analysis of the ten percent sampling tabulation of the 1982 third national population census

Advance results from the 1982 census of China are presented based on a 10 percent sample. Sections are included on age distribution, centenarians, marriage patterns, educational status, and the labor force. Several characteristics of China's population are described in this article, based on a 10% sampling tabulation of the production teams and resident groups of the whole country. Data are included for 100,380,000 people. The proportion of the population aged 0-14 is 33.60%, which marks a decline from figures in the 1964 census (40%). This decline is attributed to family planning and population control efforts. The median age is 22.91 years, which is 2.71 years older than that in the 1964 census. The % of the population aged 15-64 rose from 55.7% in 1964 to 61.5%. The dependency ratio dropped from 79.4% (1964) to 62.6%. There were 3,765 centenarians as of July, 1982; the overwhelming majority live in villages, and most (94.77%) are illiterate or semiliterate. The number of female centenarians is 2.4 times that of males. Marriages are comparatively stable in China. 63.6% of the population aged 15 and over are married, and .59% are divorced. The % of the population remaining single after age 50 is .21% for females, 2.97% for males. The average 1st marriage age is 22.80 years for females and 25.49 years for males. 60.35% of the people have had primary education or above; .44% are college graduates. In 1964, 33.58% of the population illiterate or semiliterate. At present, among people aged 12 and over, 31.90% are illiterate or semiliterate. The rural illiteracy rate is more than twice the urban rate. 51.94% of the total population is employed. Of these, 92.08% are engaged in manual labor. Males exceed females in all professions and occupations. The median age of the employed population is 30.84 years. The level of education among the employed is relatively low: 28.26% are illiterate or semiliterate, and 34.35% have had primary education only.     

Solving the part families problem in discrete-parts manufacture by simulated annealing

In the production planning and control of discrete-parts manufacture, aggregation of parts into families, on the basis of similarity, is carried out to ease both long-horizon planning and short-horizon scheduling. Additional advantages are related to those of group technology (GT), such as simplifying the flow of parts and tools and reducing both set-up and production costs. The problem of formally forming part families is presented and discussed. Previous work is reviewed and assessed. Two solution approaches, one based on a location model, the other on simulated annealing, are presented and compared along with test results. The location formulation, which results in an integer programming model solved by Lagrangian relaxation, proved capable of producing solutions of excellent quality, but only for relatively small problem instances. In contrast, simulated annealing, which is a general heuristic approach to combinatorial optimization, produced solutions of comparable quality and could handle realistically large problem instances. However, careful design of the simulated annealing algorithm is crucially important. An effective design is presented.     

分析师利益与投资建议的信息含量

 内容提要:本文分析了证券分析师的利益和我国证券分析师投资建议的信息含量。本文发现,证券分析师投资建议大多为“买入”或“中性”建议,而“卖出”建议却很少。通过对投资建议发布日附近股票超额回报率和超常交易量的研究,本文发现“买入”、“卖出”建议分别会引起股价的永久性上涨和下跌,而“中性”建议不会对股价产生显著影响。此外,被建议“买入”和“卖出”的股票的交易量也会明显地增加,特别是在建议发布的当日。这些现象说明,投资者认为分析师的建议包含了有价值的信息,因而相应地调整了对未来收益的预期以及当前最优的持股数量。股票交易的活跃给证券公司带来了佣金收入,作为对他们向市场传递有价值信息的回报。     

当代印度政坛中的雅利安人入侵理论争议初探

长期以来,由于受西方知识界对印欧文化百年研究积累的影响,＂雅利安人入侵理论＂始终位居学界主流,并进入印度与世界各国的教科书中,成为我们诠释印度古代历史的重要基础;时至今日,在后殖民学术批判风潮与印度教民族主义的推波助澜之下,此一理论却俨然成为具有高度政治争议性的论题。影响所及,不光是在印度国内的学界,更波及全世界的印度学研究社群。究竟对于＂雅利安人入侵理论＂的争论如何影响当代印度政治发展？此一理论为什么又能引起如此惊人的政治效应？各方对于此一理论的基本立场差异又是如何？透过本文的讨论,我们希望能针对这些问题提出回答。     

Cox regression analysis in presence of collinearity: an application to assessment of health risks associated with occupational radiation exposure

This paper considers the analysis of time to event data in the presence of collinearity between covariates. In linear and logistic regression models, the ridge regression estimator has been applied as an alternative to the maximum likelihood estimator in the presence of collinearity. The advantage of the ridge regression estimator over the usual maximum likelihood estimator is that the former often has a smaller total mean square error and is thus more precise. In this paper, we generalized this approach for addressing collinearity to the Cox proportional hazards model. Simulation studies were conducted to evaluate the performance of the ridge regression estimator. Our approach was motivated by an occupational radiation study conducted at Oak Ridge National Laboratory to evaluate health risks associated with occupational radiation exposure in which the exposure tends to be correlated with possible confounders such as years of exposure and attained age. We applied the proposed methods to this study to evaluate the association of radiation exposure with all-cause mortality.     

Estimating population sizes by catch-effort methods

Estimating population sizes by the catch-effort methods is of enormous importance, in particular to harvest animal populations. A unified mixture model is introduced for different catchability functions to account for heterogeneous catchabilities among individual animals. A sequence of lower bounds to the odds that a single animal is not caught are proposed and used to define pseudo maximum likelihood estimators for the population size. The one-sided nature of confidence intervals is discussed. The proposed estimation methods are presented and illustrated by numerical studies.