Population Trends in Metropolitan and Nonmetropolitan America: Selective Deconcentration and the Rural Rebound

This study uses revised annual population estimates that incorporate adjustments from the 2000 Census to backcast demographic change for U.S. counties during the 1990s. These data are supplemented with new post-censal population estimates for 2001–2003. We use these data to examine demographic trends in the late 1990s and first years of the new century. Our findings are consistent with a model suggesting that a selective deconcentration of the U.S. population is underway. Our findings also confirm the occurrence of the rural rebound in the first half of the 1990s and a waning of this rebound in the late 1990s. Post-censal data also suggest a modest upturn in nonmetropolitan population growth rates in 2001–2003.     

Gendering a Language,Liberating a People: Women Writing in Afrikaans and the 'New' South Africa

I discuss contem porary South African women's writing in Afrikaans, particularly as produced by white women. Long overlooked, this body of work has quickly become the new avant garde of South African writing, reflecting (upon) as it presages dramatic transformations in the South African social fabric. Mapping the contributions of this writing in Afrikaans, I contrast them with the absence of engagement in South African writing in English with narrative techniques concerned with the nuances and ironies, the boundary and border transgressions of women's writing in Afrikaans- of traditional styles and themes, standard subjects and narrative technologies, of the gendered formation of language itself.     

Trends,Age Patterns and Differentials in Childhood Mortality in Haiti (1960–1987)

This paper examines the trends, patterns and differentials in childhood mortality in Haiti between 1960 and 1987 with data from three surveys and one census. Data comparability is maximized by a series of adjustments, and both direct and indirect techniques are applied. The results indicate that a slow decline in childhood mortality has occurred since 1960 for the country as a whole. Neonatal survival has shown impressive gains, especially in rural Haiti. Post-neonatal mortality has not, however, declined at the same rate. Mortality between the ages of one and five years has declined at about the same pace as infant mortality, maintaining consistency with model patterns of mortality change. The overall national decline in child mortality appears to have consisted of two phases. The first occurred in rural Haiti during the late 1960s and early 1970s and was due largely to a fall in neonatal mortality. The second phase of the decline was concentrated in Port-au-Prince, and seems to have affected all ages of childhood.     

Economic Swings and Demographic Changes in the History of Latin America

In this paper we study the effects of short-term fluctuations in indicators of economic well-being on selected demographic response such as births, marriages and deaths at age intervals in eleven Latin American countries between 1910 and 1990. We use conventional distributed lag models to assess the magnitude and direction of effects and test a variety of hypotheses some of which have been posed to hold in Western Europe and others that are more specific and tailored to the Latin American context. We also compare the magnitude and direction of effects obtained among these countries with those obtained for pre-industrial Europe and uncover the existence of broadly similar patterns.     

Spatial and temporal residential density patterns from 1940 to 2000 in and around the Northern Forest of the Northeastern United States

Over the past 60 years, housing growth has outpaced population growth in the United States. Conservationists are concerned about the far-reaching environmental impacts of housing development, particularly in rural areas. We use clustering analysis to examine the pattern and distribution of housing development since 1940 in and around the Northern Forest, a heavily forested region with high amenity and recreation use in the Northeastern United States. We find that both proximity to urban areas and an abundance of natural amenities are associated with housing growth at the neighborhood level in this region. In the 1970s, counterurbanization led to higher rates of growth across rural areas. The Northern Forest now has extensive interface between forest vegetation and residential development, which has the potential to profoundly alter the ecological and social benefits of these forests.     

Methods for combining ancillary data in stochastic compartment models of cancer mortality: Generalization of heterogeneity models∗

In analyzing mortality data there may be available information from survey and other sources that describe the marginal distribution of risk factors. We present a mortality model where nationally representative survey data on risk factor distributions are combined with data on cohort mortality rates to increase information, i.e., a fixed marginal risk factor distribution is combined with a cohort model representing unobserved individual risk heterogeneity. The model is applied to lung cancer mortality in nine U.S. white male cohorts aged 30 to 70 in 1950 and followed 38 years. Estimates of the cohort specific proportions of smokers were made from the National Health Interview Survey. Comparisons are made for models with different patterns of changes with age of individual heterogeneity.     

Extended Analysis and Evidence Integration of Chloroprene as a Human Carcinogen

β-Chloroprene is used in the production of polychloroprene, a synthetic rubber. In 2010, Environmental Protection Agency (EPA) published the Integrated Risk Information System “Toxicological Review of Chloroprene,” concluding that chloroprene was “likely to be carcinogenic to humans.” This was based on findings from a 1998 National Toxicology Program (NTP) study showing multiple tumors within and across animal species; results from occupational epidemiological studies; a proposed mutagenic mode of action; and structural similarities with 1,3-butadiene and vinyl chloride. Using mouse data from the NTP study and assuming a mutagenic mode of action, EPA calculated an inhalation unit risk (IUR) for chloroprene of 5 × 10⁻⁴ per µg/m³. This is among the highest IURs for chemicals classified by IARC or EPA as known or probable human carcinogens and orders of magnitude higher than the IURs for carcinogens such as vinyl chloride, benzene, and 1,3-butadiene. Due to differences in pharmacokinetics, mice appear to be uniquely responsive to chloroprene exposure compared to other animals, including humans, which is consistent with the lack of evidence of carcinogenicity in robust occupational epidemiological studies. We evaluated and integrated all lines of evidence for chloroprene carcinogenicity to assess whether the 2010 EPA IUR could be scientifically substantiated. Due to clear interspecies differences in carcinogenic response to chloroprene, we applied a physiologically based pharmacokinetic model for chloroprene to calculate a species-specific internal dose (amount metabolized/gram of lung tissue) and derived an IUR that is over 100-fold lower than the 2010 EPA IUR. Therefore, we recommend that EPA's IUR be updated.     

Wealth Accumulation across the Adult Life Course: Stability and Change in Sociodemographic Covariate Structures of Net Worth Data in the Survey of Income and Program Participation, 1984–1991

This paper reports microlevel Tobit regression analyses of sociodemographic covariates of the life course accumulation of total household net worth data in eight waves of five distinct panels—spanning over 6 years from late 1984 through early 1991—of the Survey of Income and Program Participation (SIPP). It is found that the quadratic age–wealth relationship predicted by Modigliani's Life Cycle Hypothesis is evident in aggregate age–median wealth profiles as well as in the micro data for households with positive net worth. However, when adult status attainment variables are entered into the regression models either by themselves or in combination with marital/family status variables, the age of household head at which net worth begins to decline is far beyond the typical retirement age. In addition, the traditional criterion variables of sociological status attainment theory—educational attainment, occupational status, and earnings—are found to be positively associated with household net worth, although the net effect of occupational status generally is not statistically significant and the earnings effect is nonlinear. Further, consistent with status attainment theory, householder minority status (black, Hispanic) is negatively associated with the accumulation of net worth. It is found that both single male and single female householder status are negatively associated with the accumulation of household net worth (relative to married couple households) as is the size of the household (measured by the number of children under age 18 present). Separate logistic regression analyses show that households with zero and negative net worth are more likely than households with positive net worth to be black and have low earnings. Higher levels of educational and occupational status attainment reduce the probability of zero net worth but not the probability of negative net worth. Male- and female-headed households and households headed by Hispanics also are more likely to have zero net worth, but not negative net worth. The estimated sociodemographic covariate structures of household net worth are found to exhibit substantial stability across both waves and panels in the SIPP—although effects of the 1990–1991 recession are detectable in estimates for the 1990 panel. Possible applications of the estimated models in demographic projections of household net worth are suggested.     

Strategies for Appointment Policy Design with Patient Unpunctuality

Appointment policy design is complicated by patients who arrive earlier or later than their scheduled appointment time. This article considers the design of scheduling rules in the presence of patient unpunctuality and how they are impacted by various environmental factors. A simulation optimization framework is used to determine how to improve performance by adjusting the schedule of appointments. Prior studies (that did not include patient unpunctuality) have found that a scheduling policy with relatively consistent appointment interval lengths in the form of a dome or plateau dome rule to perform well in a variety of clinic environments. These rules still perform reasonably well here, but it is shown that a combination of variable‐length intervals and block scheduling are better at mitigating the effects of patient unpunctuality. In addition, performance improves if the use of this policy increases toward the end of the scheduling session. Survey and observational data collected at multiple outpatient clinics are used to add realism to the input parameters and develop practical guidelines for appointment policy decision making.