Who moves and who stays? Rural out-migration in Nigeria

Data from the nationally representative 1993 Migration and Urbanization Survey of Nigeria are used to simultaneously examine the patterns of rural-rural and rural-urban migration in Nigeria. A multinomial logistic regression model predicts the independent and collective association between individual, household, and regional variables and migration from rural areas to rural and urban destinations. Associations between education, religion and ethnicity and migration propensities exist at the national level. The Kanuri-Shua Arabs are generally non-migrants, the Hausa-Fulani and Yoruba are predominantly rural-rural migrants and the Igbo-Ibibio and Urhobo-Isoko-Edo are predominantly ruralurban migrants. Christians are significantly more mobile than Muslims. While the highly educated are most likely to choose an urban destination, a significant proportion migrate to other rural areas. Concern over population concentration is not supported, as rural migrants move to all regions and to urban and rural areas.     

Life and death in the sixteenth century in the City of York

Abstract Birth data obtained from the parish records of the City of York show a markedly bi-modal seasonal distribution in the sixteenth century. It appeared interesting to compare the expectation of life of individuals born during this period, during the two minimal and two maximal seasons, to determine if there was any adaptive significance in the annual variation of birth rate. No such effect could be established by this study. However, certain conclusions of considerable interest can be drawn. The survivorship functions for either sex, grouped by birth season or on the whole group, are of a rectilinear diagonal type more reminiscent of an avian population rather than man. However the York data were treated, no statistically significant difference appeared between the sexes when their expectation of life was compared, and the female death rate at all times until the end of life was somewhat higher than the male. It appeared that sixteenth-century York tended to care better for their sons than for their daughters, which also appears to be the case in some modern societies of low to moderate living standard.     

管理者关系特性对海外子公司知识获取及公司绩效的影响研究

基于组织学习理论和社会资本理论,考察了管理者关系特性对海外子公司内外部网络知识获取和企业绩效的影响。研究结果显示,母子公司管理者之间的信任和沟通频率对获取母公司知识有正向影响,海外子公司管理者和本地重要企业管理者之间的信任对获取本地商务知识有正向影响,海外子公司管理者和本地政府主要负责人之间的私人关系对获取本地制度知识有显著影响。此外,本地制度知识在母公司知识对海外子公司绩效的影响中起正向调节作用,本地商务知识起负向调节作用。     

Statistical software packages for PCs — A market survey

The increase of statistical software applications for PCs is caused by decreasing hardware costs and dramatically enhanced PC performance. Whereas in the past the domain of statistical computing has been reserved to mainframe solutions, a great number of new software packages for PCs have come out in the last five years. Therefore, the producers of established mainframe software were also forced to offer PC-based solutions. By limiting a market analysis to products with a medium set of well known statistical methods, the immense number of available products is reduced to about fifty systems. We ordered an evaluation copy of these systems to test the numerical quality, the system speed, and the performance of several procedures. Seventeen packages were made available for an extensive examination. This paper will (1) discuss the problems and the solutions of obtaining a complete and correct datamatrix that describes the entire market and (2) present the results of a comparative market analysis.     

Innovations to Make Markets More Inclusive for the Poor

Market failures, government failures and some of the characteristics of both the poor and business actors as well as their environment can act as barriers preventing the poor from participating more actively in markets, both as consumers and as producers. Private actors ‐ including for‐profit and not‐for‐profit entities, often in partnership with the public sector ‐ have been able to mitigate some of these constraints through innovations that have helped to make markets more inclusive for the poor, enabling them not just to gain access, but also to participate in ways that enhance their economic empowerment and human development. This article identifies the strategies and innovations used and devises a possible typology for them.     

Correlated linear models for the analysis of familial correlations

The problems of estimation and hypotheses testing on the parameters of two correlated linear models are discussed. Such models are known to have direct applications in epidemiologic research, particularly in the field of family studies. When the data are unbalanced, the maximum-likelihood estimation of the parameters is achieved by adopting a fairly simple numerical algorithm. The asymptotic variances and covariances of the estimators are derived, and the procedures are illustrated on arterial-blood-pressure data from the literature.     

Measurement of inequality: An attempt at unification and generalization

This paper reviews and extends the theory of ethical inequality indices. It presents a novel axiom (strict separability of social welfare orderings in rank-ordered subspaces). This axiom allows to provide joint characterizations of the most important inequality measures (Atkinson family, Kolm-Pollak family and Generalized Ginis) and of some new more general classes of indices. The whole derivation is based on weak assumptions. In an ordinal framework only continuity of the underlying ordering is required and no cardinal properties are employed.I thank two anonymous referees for helpful comments and suggestions.     

Healthy lower backs in the construction industry in Sweden

This corss-sectional study exmaines the relationship between healthy lower and psychosocial and physical factors in a random sample of 1773 male construction workers. Infoamtion on lower back status, lifestyle habits, stress, psychosomatic and psychological symptoms, psychosocizal demands and resoruces and physical workload were collected by means of a postal questionnaire. Measures of psycholocial and physical factors were based on factor analysis of the data. The criterion variable 'healthy lower back' (HLB)—no lifetime history of low back pain—proved to be valid compared with an interview and a physical examination. A total of 216 workers (12%) reported HLB. The prevalance rate decreased significantly with increasing age. The prevalence rate of HLB was 6% among workers reporting high stress levels. It was postively influenced when there was a balance between demands and resoruces. A low level of physical workload also increased the prevalence rate of HLB. When age, lifestyle and physical factors were kept constant in a multivariate analysis high scores on the discretions index and low scores on eh psychosomatic, psychological and stress indices cosntributed significantly to an increase prevalence rate of HLB.     

Sampling properties of estimators of the log-logistic distribution with application to Canadian precipitation data

We consider the probability-weighted moment and the maximum-likelihood estimators of two parameters in the log-logistic distribution. Quantile estimators are obtained using both methods. The distributional properties of these estimators are studied in large samples, via asymptotic theory, and in small and moderate samples, via Monte Carlo simulation. The distribution is shown to be appropriate for a wide variety of meteorological data.     

Head movement during listening turns in conversation

In five subjects, head movement during conversation was monitored by polarised light goniometry, and recorded alongside speech and a signal proportional to peak amplitude of sound waves (peak loudness). Kinematic properties of listeners' head movements, such as amplitude, frequency and cyclicity, differentiated various conversational functions. That is, they were function-specific: symmetrical, cyclic movements were employed to signal yes, no or equivalents; linear, wide movements anticipated claims for speaking; narrow linear movements occurred in phase with stressed syllables in the other's speech (ynchrony movements); and wide, linear movements occurred during pauses in the other's speech. That, it is argued, bears upon the relation between thesignalling of communicative intentions and the synchronisation of interactional rhythm. Thus, the former appears to determine the timing and tempo of responses such as yes and no, while the latter determines the regulation of synchrony movements. The manner in which these factors interact in other conversational functions and their theoretical implications are discussed.