U.S. births and limit cycle Models

Lee's (1974) formal demographic feedback models summarize the implications for births and age-structure of neo-Malthusian theories of baby booms such as those of Easterlin. For some parameter values, such models imply sustained cycles, so-called "limit cycles", in births. Frauenthal and Swick recently reestimated a continuous-age version of Lee's basic cohort model with U.S. series and, contrary to Lee's original findings, concluded that "limit cycles oscillations have been occurring in U.S. births." This article disputes their conclusion, ascribing it to an inconsistency in detrending procedures. Furthermore, it corrects Lee's original conclusion by showing that his alternative period labor-force feedback model, estimated from U.S. series, leads to cycles of implausibly long period. This article thus reopens the question of whether any feedback model could account for the observed cycles in U.S. births.     

Evaluating the Slavonian census of 1698. Part I: Structure and meaning

Microsimulation, other demographic tools, and evidence of history and ethnography are used to evaluate an important 17th century household census. Linguistic, ethnographic, and internal evidence allow adjustment of anomalies in census categories. Microsimulation based on historically and ethnographically plausible rates and household formation scenarios produces simulated households in accord with those of the adjusted census. Results permit estimation of the true population of the region, of the kinship and age composition of households under frontier conditions, and the probable future composition of households as the frontier stabilized and land shortage began to exert pressure for greater density and household complexity. Part I concentrates on historical, ethnographic, and linguistic evidence.On utilise ici les techniques de microsimulation, divers outils démographiques et les témoignages de l'histoire et de l'ethnographie pour évaluer un important recensement des ménages réalisé au XVII^e siècle. Des preuves linguistiques, ethnographiques et internes permettent de corriger des anomalies dans les catégories recensées. Une microsimulation basée sur des taux que l'histoire et l'ethnographie rendent plausibles, et des scénarios de formation des ménages donnent des nombres de ménages en accord avec ceux obtenus par le recensement corrigé. Les résultats permettent de fournir une estimation de la population réelle de la région, de la composition par âge et par parenté des ménages, sous des conditions de frontières. Ils donnent également la composition probable des ménages à venir tandis que les frontières se stabilisent et que le manque de terres commence à exercer une pression en vue d'une plus forte densité et d'une plus grande complexité des ménages. La première partie se concentre sur les témoignages historiques, ethnographiques et linguistiques.     

Aids and the elderly of thailand: projecting familial impacts

We apply aggregate demographic analysis and computer microsimulation to project the number of older Thais who will lose children to AIDS during their own lifetimes and to assess their involvement with ill children through caregiving and coresidence. Parental bereavements from AIDS are predicted to peak at around 80,000 per year between 2003 and 2007. Despite an HIV prevalence of only 2%, 13% of Thais who were over age 50 as of 1995 are likely to experience the loss of at least one adult child to AIDS, and 12% of them will lose multiple children. The chance of losing an adult child during one's lifetime will be 70% higher than if there were no AIDS epidemic.     

Cohort Succession in the Timing of Marriage Among the Children of Turkish and Moroccan Immigrants

European Journal of Population - In this paper, we introduce cohort succession in the study of marriage behaviour among the children of immigrants. Research among majority populations in developed...     

The cohort feedback model with symmetric net maternity

"In this paper we consider the simplest and most widely used demographic feedback model, the birth-response cohort feedback model. In the case of symmetric net maternity, we put the model into a form in which one of the rare global bifurcation theorems in the mathematical literature can be brought to bear. As a consequence, we prove that the model has solutions with period exactly twice the mean age of net maternity for at least a specified range of parameter values which include cycles of non-infinitesimal amplitude." (SUMMARY IN FRE)     

Grade of membership models in low dimensions

Grade of Membership (GoM) Models have always been presented by their inventors as statistical applications of fuzzy set theory. This paper develops an alternative formulation, recasting GoM as a geometric dimensionality-reduction technique in terms of an underlying family of metrics, exposing a close relationship with Principal Components. The geometric viewpoint facilitates intuitive understanding and guides an investigation into the robustness of GoM estimates to violations of assumption, with test cases drawn from the National Survey of Families and Households. Analysis is restricted to visualizable, low-dimensional cases with two pure types and 3 to 9 dichotomous variables, and to “conditional” GoM, the version more commonly used but less commonly studied. In these low-dimensional settings, I find GoM to be a successful technique for recovering an underlying gradient among individuals when such a gradient is actually present. GoM is only moderately sensitive to moderate violations in its assumptions. In the cases studied, GoM solutions turn out to be remarkably close to Principal Component solutions. This research has been supported by Grant R01 AG09781 from the Demography and Population Epidemiology Section of the U.S. National Institute on Aging under Richard Suzman's direction. I am grateful to Burton Singer for early suggestions and provision of the GoM3 program, and to Bryan Lincoln of the Berkeley NIA Center for the Economics and Demography of Aging.     

Career Counseling for Women Preparing to Leave Abusive Relationships: A Social Cognitive Career Theory Approach

Career counselors work with people from varied segments of society. For battered women, some of the challenges they face from intimate partner violence may significantly influence their career exploration and decision making. Social cognitive career theory (SCCT; R. W. Lent, S. D. Brown, & G. Hackett, 1994) is a framework that has important implications for working with these women. In this article, the authors present the unique career needs of battered women terminating abusive relationships, the relevance of SCCT to this population, strategies for using SCCT when working with these women, and a case study illustrating effective use of SCCT.     

Relationships between period and cohort life expectancy: gaps and lags

This paper offers an empirical and analytic foundation for regarding period life expectancy as a lagged indicator of the experience of real cohorts in populations experiencing steady improvement in mortality. We find that current period life expectancy in the industrialized world applies to cohorts born some 40-50 years ago. Lags track an average age at which future years of life are being gained, in a sense that we make precise. Our findings augment Ryder's classic results on period-cohort translation.     

The Sisters’ Riddle And The Importance Of Variance When Guessing Demographic Rates From Kin Counts

Goldman (1978) has proposed a formula derived from stable population theory for estimating growth rates from certain counts of younger and older sisters in a population. Computer microsimulation outputs show extraordinarily large statistical errors for estimation when stable population assumptions are modified to allow for random variability such as would be encountered with field work on small populations. A derivation of Goldman’s formula on more interpretable lines than that in Goldman (1978) identifies a source of variance special to this particular formula so that the large statistical errors for this example need not count in general against the feasibility of estimating demographic rates from counts of kin.