A comparative study of correlation coefficients in spatially MRSI-observed neurochemicals from multiple sclerosis patients

In measuring the association between magnetic resonance spectroscopic imaging (MRSI)-observed neurochemicals from multiple sclerosis (MS) patients, the classic correlation coefficients such as the Pearson's r, Spearman's ρand Kendall's τdo not take into account the spatial dependence of the observations. This paper reports a comparative study on these classic correlation coefficients (Pearson's r, Spearman's ρand Kendall's τ) and some more recent correlation coefficients (Tjostheim's a, the modified t) that take into account the spatial dependence of the intensities of the concentrations of several neurochemicals in MS patients. Our study indicates that the use of the classic correlation coefficients that ignores the spatial dependence of the observations may overestimate the statistical significance of the results.     

Corporate planning in domestic airlines— An Indian case study

In this article the author considers the problems of planning in the airline industry, drawing specifically on experience in the domestic Indian airline. The article seeks to examine some of the strategic issues relevant to domestic airlines which, while related here to the Indian environment, may be seen to be pertinent in most developing countries.     

Mortality differentials among immigrant populations in Canada

Mortality among different groups of migrants to Canada is compared with that of native-born Canadians and with trends in the migrants' countries of origin, using data for the period 1981-1985. Results show that life expectancy at birth among migrants in Canada is generally higher than that of the populations at place of origin and destination. (SUMMARY IN FRE AND SPA)     

Place and Child Health: The Interaction of Population Density and Sanitation in Developing Countries

A long literature in demography has debated the importance of place for health, especially children’s health. In this study, we assess whether the importance of dense settlement for infant mortality and child height is moderated by exposure to local sanitation behavior. Is open defecation (i.e., without a toilet or latrine) worse for infant mortality and child height where population density is greater? Is poor sanitation is an important mechanism by which population density influences child health outcomes? We present two complementary analyses using newly assembled data sets, which represent two points in a trade-off between external and internal validity. First, we concentrate on external validity by studying infant mortality and child height in a large, international child-level data set of 172 Demographic and Health Surveys, matched to census population density data for 1,800 subnational regions. Second, we concentrate on internal validity by studying child height in Bangladeshi districts, using a new data set constructed with GIS techniques that allows us to control for fixed effects at a high level of geographic resolution. We find a statistically robust and quantitatively comparable interaction between sanitation and population density with both approaches: open defecation externalities are more important for child health outcomes where people live more closely together.     

Some issues for cooperative learning and intercultural education

This article connects the two fields of cooperative learning and intercultural education. We argue that cooperative learning strategies need to be equipped with intercultural understandings. Two key points that are raised here are: (1) that issues of competitiveness amongst learners and students must be dealt with head on rather than treating it from the sidelines or by brushing them aside; and (2) for learning to take place in a truly cooperative manner, there must be an emphasis on an intercultural focus within the curriculum; the content of knowledge within the curriculum needs to be non-centric. This article emphasizes that cooperative learning strategies are effective when the curricular knowledge taught in the school is drawn from all groups (dominant, subordinate or minority groups).     

The Effects of Participation and Resources on Democratic Attitudes: Role of Social Capital in Four Latin and South American Countries

ABSTRACT

Social capital research in Latin and South American countries has been gravely limited by the absence of valid measures of social capital. This study seeks to create a scale for measuring social capital in the Latin and South American context using exploratory and confirmatory statistical procedures. It also seeks to test the effect of social capital on democratic attitudes in Latin America through structural equation modeling methods. Analysis of four countries in Latin and South America suggests that social capital is positively related to democratic attitudes. Recommendations for future studies are highlighted, and scale properties and outcomes are discussed.     

A mathematical model of a population genetics: Effects of genetic variation on homosexuality

This study deals with simple mathematical models for the purpose of generating testable prediction in genetics. The genetic effects in human population are because of the following four factors, (i) paternal, (ii) maternal, (iii) environmental and (iv) idiopathic. For the measurement of genetic characteristics, the environment also plays an important role. In the present paper we analyze this linkage for homosexuality for the first three factors because the fourth one affects a very little population. This study provides genetics and evolutionary basis for making generating testable predictions specifically where the environmental factors affect the characteristics of genes which also influence homosexuality. The effect of environment on homosexuality is highlighted because earlier studies confined only up to the paternal and maternal linkages. We consider two types of selections (i) direct selection with environmental effects (ii) combined selection with direct, maternal and environmental effects. The objective of this investigation is to provide the conditions for the maintenance of genetic variation of genotype of male and female. We concentrate on highlighting homosexuality as a result of variation in genes. Numerical results are obtained by taking illustration. The sensitivity analysis is carried out to explore homosexuality in terms of fitness loss and fitness gain.