An Economic Analysis of the Gap Between Desired and Actual Fertility: The Case of Spain

Family size is the outcome of sequential decisions influenced both by preferences and by ongoing changes in the environment where a family lives. During the last two decades, the gap between the number of children women prefer and their actual fertility has widened in Spain. The paper uses the 1985 and 1999 Spanish Fertility Surveys to study whether the tightening of the labor market and worsening of economic conditions in Spain during the last 20 years are important determinants of this change. I find that women facing high unemployment rates in their mid-twenties tend to restrict their fertility below their ideal level. Among women in the labor force, the stability of a public sector job lessens the difficulties of balancing employment and family and of achieving preferred fertility. Temporary contracts work in the opposite direction. Findings are robust to the inclusion of controls for within-couple discrepancies in either preferences or religious affiliation.

数字“七”在中俄两国文化中象征意义的对比

通过数字“七”在汉俄两国文化中象征意义的对比 ,反映出两国文化的巨大差异 ,强调外语学习过程中了解外国社会文化知识的重要性。     

Lot Sampling Distributions for Bounded Number of Nonconformities

Attributes sampling is an important inspection tool in areas like product quality control, service quality control or auditing. The classical item quality scheme of attributes sampling distinguishes between conforming and nonconforming items, and measures lot quality by the lot fraction nonconforming. A more refined quality scheme rates item quality by the number of nonconformities occurring on the item, e.g., the number of defective components in a composite product or the number of erroneous entries in an accounting record, where lot quality is measured by the average number of nonconformities occurring on items in the lot. Statistical models of sampling for nonconformities rest on the idealizing assumption that the number of nonconformities on an item is unbounded. In most real cases, however, the number of nonconformities on an item has an upper bound, e.g., the number of product components or the number of entries in an accounting record. The present study develops two statistical models of sampling lots for nonconformities in the presence of an upper bound a for the number of nonconformities on each single item. For both models, the statistical properties of the sample statistics and the operating characteristics of single sampling plans are investigated. A broad numerical study compares single sampling plans with prescribed statistical properties under the bounded and unbounded quality schemes. In a large number of cases, the sample sizes for the realistic bounded models are smaller than the sample sizes for the idealizing unbounded model.     

The generalized Poisson-binomial distribution and the computation of its distribution function

The Poisson-binomial distribution is useful in many applied problems in engineering, actuarial science and data mining. The Poisson-binomial distribution models the distribution of the sum of independent but non-identically distributed random indicators whose success probabilities vary. In this paper, we extend the Poisson-binomial distribution to a generalized Poisson-binomial (GPB) distribution. The GPB distribution corresponds to the case where the random indicators are replaced by two-point random variables, which can take two arbitrary values instead of 0 and 1 as in the case of random indicators. The GPB distribution has found applications in many areas such as voting theory, actuarial science, warranty prediction and probability theory. As the GPB distribution has not been studied in detail so far, we introduce this distribution first and then derive its theoretical properties. We develop an efficient algorithm for the computation of its distribution function, using the fast Fourier transform. We test the accuracy of the developed algorithm by comparing it with enumeration-based exact method and the results from the binomial distribution. We also study the computational time of the algorithm under various parameter settings. Finally, we discuss the factors affecting the computational efficiency of the proposed algorithm and illustrate the use of the software package.     

On Exact K-optimal Designs Minimizing the Condition Number

A new design criterion based on the condition number of an information matrix is proposed to construct optimal designs for linear models, and the resulting designs are called K-optimal designs. The relationship between exact and asymptotic K-optimal designs is derived. Since it is usually hard to find exact optimal designs analytically, we apply a simulated annealing algorithm to compute K-optimal design points on continuous design spaces. Specific issues are addressed to make the algorithm effective. Through exact designs, we can examine some properties of the K-optimal designs such as symmetry and the number of support points. Examples and results are given for polynomial regression models and linear models for fractional factorial experiments. In addition, K-optimal designs are compared with A-optimal and D-optimal designs for polynomial regression models, showing that K-optimal designs are quite similar to A-optimal designs.     

NO ROOM FOR ABUSE

In Canada, media reports on health care tend to focus on the high costs of the health care system; reporting privileges the economic aspects of this social service. In the Canadian system, long-term care or chronic care is a type of service that is situated within the health care system. Long-term care institutions typically house older individuals who have lost a significant amount of autonomy and require constant care. Until recently, the services dispensed within these institutions were unseen by the media, and thus the public did not reflect much on these services. The publication of the Report of the Royal Commission on the Future on Health Care in Canada in 2002 has fostered a growing public awareness of the vulnerability of older individuals and those with chronic illnesses, and their relationship with their care-givers. Although it may be the case that the typical care for such persons in these situations is now emerging from a zone of invisibility, it is uncertain that the media coverage accurately portrays the realities of institutionalized care-giving. This essay examines the care practices in long-term care institutions in order to understand the processes at work in an environment in which care is commodified. The ‘area’ in which this caring labour is located is an area where constant moral compromise can create a climate where abuse can become endemic. This paper considers these environments and the potential for abuse in them in relation to the concept of ‘grey zone’, first formulated by Primo Levi and later adapted by Giorgio Agamben and Claudia Card, as well as in relation to the related concept ‘bare life’, also formulated by Agamben. The author argues that the ‘greyness’ produced by care practices that are bound to a cost-effective and task-oriented framework create an environment that is not conducive to proper moral behaviour.     

煤矿企业人因事故影响因素的灰色关联分析

针对煤炭企业人因事故多发问题,采用聚类分析法把人因事故原因归结为6大因素,而这6大因素通过灰色关联度计算后得出以矿工素质因素、矿工心理因素和管理因素为主,提出预防人因事故的＂意识——学习——环境＂相结合的安全管理模式。研究结果为减少煤炭企业人因事故的发生有指导意义。     

完全模糊线性系统的非正模糊近似解

针对完全模糊线性系统A~x=~b,其中A~,~x和b~分别为模糊数矩阵和模糊数向量,利用广义LR-模糊数及其近似算法,讨论了完全模糊线性系统的非正模糊近似解.     

灰色马尔可夫模型在房价指数预测中的应用

灰色马尔可夫模型预测兼有灰色预测和马尔可夫链预测的优点,并能对较短的时间序列数据进行建模计算。文章尝试将该模型应用于房价指数的预测分析,并对2003年7月到2005年7月间的中房上海住宅指数和办公楼指数进行了实证分析,结果表明模型的拟合精度较高,在房价指数的预测中有较强的适用性。     

A Generalization to Bivariate Mittag–Leffler and Bivariate Discrete Mittag–Leffler Autoregressive Processes

A generalization of the Gaver and Lewis (1980 Gaver , D. P. , Lewis , P. A. W. ( 1980 ). First order autoregressive gamma sequences and point processes . Adv. Appl. Probab. 12 : 727 – 745 .[Crossref], [Web of Science ®] , [Google Scholar]) model of first-order autoregressive process with marginals as bivariate Mittag–Leffler distribution is obtained. A necessary and sufficient condition for stationarity of the process is established. Autoregressive process with marginals follow bivariate discrete Mittag–Leffler distribution is also developed. The unknown parameters of the processes are estimated and some numerical results of the estimations are given.