Spatio-Temporal Dimensions of Child Poverty in America, 1990-2010.

The persistence of childhood poverty in the United States, a wealthy and developed country, continues to pose both an analytical dilemma and public policy challenge, despite many decades of research and remedial policy implementation. In this paper, our goals are twofold, though our primary focus is methodological. We attempt both to examine the relationship between space, time, and previously established factors correlated with childhood poverty at the county level in the continental United States as well as to provide an empirical case study to demonstrate an underutilized methodological approach. We analyze a spatially consistent dataset built from the 1990 and 2000 U.S. Censuses, and the 2006-2010 American Community Survey. Our analytic approach includes cross-sectional spatial models to estimate the reproduction of poverty for each of the reference years as well as a fixed effects panel data model, to analyze change in child poverty over time. In addition, we estimate a full space-time interaction model, which adjusts for spatial and temporal variation in these data. These models reinforce our understanding of the strong regional persistence of childhood poverty in the U.S. over time and suggest that the factors impacting childhood poverty remain much the same today as they have in past decades.

Primary care availability and emergency department use by older adults: a population-based analysis.

OBJECTIVES: To assess the relationship between the number of primary care providers (PCPs) in an area and emergency department (ED) visits by older adults. DESIGN: Population-based cross-sectional observational study. SETTING: Nonfederal EDs in North Carolina in 2010. PARTICIPANTS: All older adults (n = 640,086) presenting to a nonfederal ED in North Carolina in 2010. MEASUREMENTS: The primary outcome was the number of ED visits by older adults in each ZIP code per 100 adults aged 65 and older living in that ZIP code. A secondary outcome was the number of ED visits not resulting in hospital admission per 100 older adults. The primary predictor variable was the number of PCPs per 100 older residents for each ZIP code. Covariates included those representing healthcare need (Medicare hospitalizations, nursing home beds), predisposing factors for healthcare use (race, education, population density of older adults), and enabling factors (distance to the nearest ED). RESULTS: In a multivariable regression model corrected for spatial clustering, ZIP code characteristics associated with ED visits included more hospitalizations by Medicare beneficiaries, more nursing home beds, and closer proximity to an ED. Number of PCPs per 100 older adult residents in each ZIP code was not associated with ED use, and the 95% confidence limit indicates at most a small effect of PCP availability on ED use. CONCLUSION: These findings suggest that primary care availability has at most a limited effect on ED use by older adults in North Carolina.

Spatial variation in poverty-generating processes: Child poverty in the United States.

This study builds on research demonstrating that sub-regions within the United States have different processes that abet poverty and that child poverty is spatially differentiated. We focus on the social attributes of the local area to assess what the geographic place represents in terms of social characteristics, namely racial/ethnic composition and economic structure, and to resolve apparent inconsistencies in poverty research. Using spatial regime and spatial error regression techniques to analyze county census data, we examine spatial differentiation in the relationships that generate child poverty. Our approach addresses the conceptual and technical aspects of spatial inequality. Results show that local-area processes are at play with implications for more nuanced theoretical models and anti-poverty policies that consider systematic differences in factors contributing to child poverty according to the racial/ethnic and economic contexts.

Temporal and spatial variation in age-specific net migration in the United States.

As fertility differences in the United States diminish, population redistribution trends are increasingly dependent on migration. This research used newly developed county-level age-specific net migration estimates for the 1990s, supplemented with longitudinal age-specific migration data spanning the prior 40 years, to ascertain whether there are clear longitudinal trends in age-specific net migration and to determine if there is spatial clustering in the migration patterns. The analysis confirmed the continuation into the 1990s of distinct net migration "signature patterns" for most types of counties, although there was temporal variation in the overall volume of migration across the five decades. A spatial autocorrelation analysis revealed large, geographically contiguous regions of net in-migration (in particular, Florida and the Southwest) and geographically contiguous regions of net out-migration (the Great Plains, in particular) that persisted over time. Yet the patterns of spatial concentration and fragmentation over time in these migration data demonstrate the relevance of this "neighborhood" approach to understanding spatiotemporal change in migration.

Explaining human settlement patterns in a recreational lake district: Vilas County, Wisconsin, USA.

Lakeshore development in Vilas County, northern Wisconsin (USA) is heterogeneous, ranging from lakes that are surrounded by homes and commercial establishments to lakes that have no buildings on their shorelines. Development in this recreational area has increased, and since the 1960s over half of new homes have been built on the lakeshore. We examined building density around lakes in relationship to 11 variables, including in-lake, shoreline, and social characteristics. Buildings in many parts of northern Wisconsin tend to be concentrated around shorelines; in Vilas County 61% of all medium-sized buildings (our proxy for residential development) on private land were < or =100 m of a lake. The probability of development on a lake was largely related to lake surface area, with larger, more accessible lakes showing a higher probability of development. Building density along shorelines varied with travel cost, lake surface area, presence of wetlands, and extent of public land ownership. Building density was greater on larger, more accessible lakes that were surrounded by forest (as opposed to wetlands) and public lands. Gaining a more precise understanding of human settlement patterns can help direct planning and resource protection efforts to lakes most likely to experience future development.