Age patterns of marital fertility: revising the Coale-Trussell method

"This article revises the Coale-Trussell method for analyzing data from the World Fertility Survey by proposing and testing alternative log-linear and log-multiplicative models. The models, in one form or another, represent the structural constraint underlying the Coale-Trussell method on the variation in the age pattern of human fertility. With a Poisson distribution assumption for the number of births, several parameters of the models are simultaneously estimated via maximum likelihood. It is shown that the new approach can be adopted whenever fertility limitation is compared across multiple populations or subpopulations."     

Exploring Nonnormative Coresidence in Urban China: Living With Wives’ Parents

We model histories between two cohorts of urban Chinese couples (N = 1,191) of a rarely studied living arrangement—coresidence with the wife's parents—using a dynamic life history analysis in contrast to previous cross‐sectional studies of coresidence. We examine patterns of entry into and exit from coresidence with the wife's parents, comparing the predictive power of modernization theory to the effect of demographic change and the resources and needs of each generation. Given China's well‐known patrilineal family system, we find a surprisingly high number of couples ever residing nonnormatively, and significant differences between cohorts in what determines the pattern of coresidence. Resources and needs that reflect conscious choices to coreside most strongly influence nonnormative coresidence. Its importance may increase as the children of the One‐Child Family Policy grow up and marry.     

Analysis of accelerated life tests with weibull failure distribution via generalized linear models

Efficient industrial experiments for reliability analysis of manufactured goods may consist in subjecting the units to higher stress levels than those of the usual working conditions. This results in the so called "accelerated life tests" where, for each pre-fixed stress level, the experiment ends after the failure of a certain pre-fixed proportion of units or a certain test time is reached. The aim of this paper is to determine estimates of the mean lifetime of the units under usual working conditions from censored failure data obtained under stress conditions. This problem is approached through generalized linear modelling and related inferential techniques, considering a Weibull failure distribution and a log-linear stress-response relationship. The general framework considered has as particular cases, the Inverse Power Law model, the Eyring model, the Arrhenius model and the generalized Eyring model. In order to illustrate the proposed methodology, a numerical example is provided.     

Book Review: The Skeptical Environmentalist: Measuring the Real State of the World. Bjorn Lomborg. Cambridge U.K.: Cambridge University Press

Population and Environment -     

Searching again and again. Inclusion, heterogeneity and social work research

Summary Once upon a time there was a society of priests who built aCelestial City with gates secured by word combination locks.The priests were masters of the Word and, within the City, ascendinglevels of power and treasure became accessible to those whocould learn ascendingly intricate levels of Word Magic. At thevery top level, the priests became gods; and because they thenhad nothing left to seek, they engaged in games with which topass the long hours of eternity. In particular, they liked toride their strong, sure-footed steeds around and around theperimeter of heaven: now jumping word hurdles, now playing polowith concepts of the moon and the stars, now reaching up totouch that pinnacle, that Splinter of Refined Understandingcalled Superunderstanding, which was the brass ring of theirmerry-go-round (Williams, 1991, p. 1)     

An Optimum Population for North and Latin America

The population of North America, which now stands at nearly 300 million people, is projected to double in about 60 years, while the population of nearly 500 million people in South America is projected to double in less than 40 years. Both of these populations obtain more than 99% of their food from the land, and this percentage will increase as these populations grow. Maintaining fertile and ample land is critical if these large populations are to be fed. Soil degradation by soil erosion is a serious problem on both continents. In addition, agricultural land is being lost to urbanization and highways because of rapid population growth. Nearly a half hectare of land is needed for urbanization for each person added to the North American population; this is already causing serious problems with agriculture in some states in the United States. The land resources that are critical for food production will be especially so if the populations of both continents double to nearly 2 billion. Land resources will also be critical when both continents deplete their fossil fuels in less than 100 years and have to turn to renewable energy sources. With about 2 billion people, there will be serious shortages of food, water, and energy resources and the standard of living will significantly decline. Our assessment suggests that for a relatively high standard of living in North and South America each continent should have no more than about 200 million people, or a total of 400 million.     

Just How Do I Love Thee?: Marital Relations in Urban China

Marriage quality is much studied, but mostly in the West. This study applies such research to a large, representative sample of couples from urban China using a multidimensional measure of marriage quality. Characteristics unique to Chinese families—the importance of parental approval of mates and the importance of marriage type—continue to exert a strong influence on the pattern of marriage quality. However, results also support Western feminist arguments that egalitarian behaviors—division of chores and decision making—and attitudes strongly impact marriage quality, but in sometimes unique ways for each gender. As in the West, children are associated with lower marriage quality, partly through increasing domestic inequality, but only in certain types of marriages.     

Impact of Population Growth on Food Supplies and Environment

Population and Environment -     

Multivariate survival mixed models for genetic analysis of longevity traits

A class of multivariate mixed survival models for continuous and discrete time with a complex covariance structure is introduced in a context of quantitative genetic applications. The methods introduced can be used in many applications in quantitative genetics although the discussion presented concentrates on longevity studies. The framework presented allows to combine models based on continuous time with models based on discrete time in a joint analysis. The continuous time models are approximations of the frailty model in which the baseline hazard function will be assumed to be piece-wise constant. The discrete time models used are multivariate variants of the discrete relative risk models. These models allow for regular parametric likelihood-based inference by exploring a coincidence of their likelihood functions and the likelihood functions of suitably defined multivariate generalized linear mixed models. The models include a dispersion parameter, which is essential for obtaining a decomposition of the variance of the trait of interest as a sum of parcels representing the additive genetic effects, environmental effects and unspecified sources of variability; as required in quantitative genetic applications. The methods presented are implemented in such a way that large and complex quantitative genetic data can be analyzed. Some key model control techniques are discussed in a supplementary online material.     

Ethnic Bias in California Courts: A Case Study of Chicano and Anglo Felony Defendants

This paper reports the results of a study designed to examine the possibility that Mexican-Americans charged with felonies receive biased treatment in California courts. Using data from superior courts in Fresno, California, it is shown that, when charged with similar crimes, Chicanos and Anglos in this district are given quite similar treatment–there is no observable judicial bias. In addition, this study shows a much stronger relationship between seriousness of charge and length of sentence (if guilty) than other earlier studies have. This is attributed to California's determinate sentencing law, which, it appears, forces the courts to give heavy and relatively uniform weight to legally relevant variables in sentencing.