Geographic Unit Of Analysis Research Articles

A PAISAGEM E OS ALUNOS DE GRADUAÇÃO DO DEPARTAMENTO DE GEOGRAFIA DA FACULDADE DE FILOSOFIA, LETRAS E CIÊNCIAS HUMANAS (FFLCH), DA UNIVERSIDADE DE SÃO PAULO (USP)

In geography, the study of spatial arrangements can be made by various categories or geographic units of analysis, such as: space, region, territory, place, and landscape. The adoption of these categories generated different lines of geographical thought, providing theoretical and methodological approaches that were very important for geographical science and its thought lines, including the approach that adopts the landscape as a geographic unit of analysis. Aiming to understand the knowledge about landscape that students of the Bachelor of Geography from the Department of Geography/FFLCH/USP have before attending elective discipline Landscape Geographic Theory, they answered questionnaires from 2006 to 2011. Analysis of the results allowed the comparison of: a) the curricular structure of the undergraduate major in Geography among the Sao Paulo State Universities; b) verify among the universities the existence of disciplines about landscape; c) investigate the main definition about landscape elaborated by the students; d) investigate the authors and literature’s sources previously known by students; e) and finally suggest changes that can increase the value of landscape as a category of analysis in the education of the students majoring in Geography at the Department of Geography, University of Sao Paulo.

Location, Location, Location: Geographic Clustering of Lower-Extremity Amputation Among Medicare Beneficiaries With Diabetes

OBJECTIVELower-extremity amputation (LEA) is common among persons with diabetes. The goal of this study was to identify geographic variation and the influence of location on the incidence of LEA among U.S. Medicare beneficiaries with diabetes.RESEARCH DESIGN AND METHODSWe conducted a cohort study of beneficiaries of Medicare. The geographic unit of analysis was hospital referral regions (HRRs). Tests of spatial autocorrelation and geographically weighted regression were used to evaluate the incidence of LEA by HRRs as a function of geographic location in the U.S. Evaluated covariates covered sociodemographic factors, risk factors for LEA, diabetes severity, provider access, and cost of care.RESULTSAmong persons with diabetes, the annual incidence per 1,000 of LEA was 5.0 in 2006, 4.6 in 2007, and 4.5 in 2008 and varied by the HRR. The incidence of LEA was highly concentrated in neighboring HRRs. High rates of LEA clustered in contiguous portions of Texas, Oklahoma, Louisiana, Arkansas, and Mississippi. Accounting for geographic location greatly improved our ability to understand the variability in LEA. Additionally, covariates associated with LEA per HRR included socioeconomic status, prevalence of African Americans, age, diabetes, and mortality rate associated with having a foot ulcer.CONCLUSIONSThere is profound “region-correlated” variation in the rate of LEA among Medicare beneficiaries with diabetes. In other words, location matters and whereas the likelihood of an amputation varies dramatically across the U.S. overall, neighboring locations have unexpectedly similar amputation rates, some being uniformly high and others uniformly low.

Neighborhood Poverty Rate and Mortality in Patients Receiving Critical Care in the Academic Medical Center Setting

Poverty is associated with increased risk of chronic illness but its contribution to critical care outcome is not well defined. We performed a multicenter observational study of 38,917 patients, aged ≥ 18 years, who received critical care between 1997 and 2007. The patients were treated in two academic medical centers in Boston, Massachusetts. Data sources included 1990 US census and hospital administrative data. The exposure of interest was neighborhood poverty rate, categorized as < 5%, 5% to 10%, 10% to 20%, 20% to 40% and > 40%. Neighborhood poverty rate is the percentage of residents below the federal poverty line. Census tracts were used as the geographic units of analysis. Logistic regression examined death by days 30, 90, and 365 post-critical care initiation and in-hospital mortality. Adjusted ORs were estimated by multivariable logistic regression models. Sensitivity analysis was performed for 1-year postdischarge mortality among patients discharged to home. Following multivariable adjustment, neighborhood poverty rate was not associated with all-cause 30-day mortality: 5% to 10% OR, 1.05 (95% CI, 0.98-1.14; P = .2); 10% to 20% OR, 0.96 (95% CI, 0.87-1.06; P = .5); 20% to 40% OR, 1.08 (95% CI, 0.96-1.22; P = .2); > 40% OR, 1.20 (95% CI, 0.90-1.60; P = .2); referent in each is < 5%. Similar nonsignificant associations were noted at 90-day and 365-day mortality post-critical care initiation and in-hospital mortality. Among patients discharged to home, neighborhood poverty rate was not associated with 1-year-postdischarge mortality. Our study suggests that there is no relationship between the neighborhood poverty rate and mortality up to 1 year following critical care at academic medical centers.

Community-Level Correlates of Hospitalizations for Persons With Schizophrenia

Community-Level Correlates of Hospitalizations for Persons With Schizophrenia

A model of foreign direct investment flows at the municipal level in South Africa

PurposeThe purpose of this paper is to assess the relationship between South Africa's foreign direct investment (FDI) and economic fundamentals at the municipal level.Design/methodology/approachThe paper develops a data set and an econometric model to analyze FDI flows at the municipal level in South Africa.FindingsThe empirical results derived from municipal level data support the findings in some of the established literature (which for the most part uses country‐level data) and indicates: that FDI tends to flow to areas with high factor (capital, labour and land) productivity; and that increases in higher labour productivity lead to higher investment.Research limitations/implicationsThis paper has used a cross‐section of municipalities. A further area of research would be to carry out a similar exercise with panel data.Practical implicationsThese findings indicate that FDI flows can be considered at the municipal level and this justifies the need for careful selection of the geographic basis for economic policy and development planning.Originality/valueWhereas most studies on FDI use country‐level data as standard geographic units of analysis, this paper analyzes FDI flows at the municipal level.

Risk‐Focused Policing at Places: An Experimental Evaluation

Drawing upon literature from developmental criminology and place‐based policing, the Redlands, California Police Department developed the Risk‐Focused Policing at Places (RFPP) approach to preventing and reducing juvenile delinquency. The RFPP program is a community‐oriented policing and problem‐solving strategy that targets risk and protective factors related to delinquency and problem behaviors of youths living in census block group areas. We used a matched block randomized experimental design to evaluate the effects of the program on youths living in 26 census block groups in Redlands. We find that the RFPP program did not influence self‐reported delinquency, or perceptions of risk and protective factors and police legitimacy. We argue that the primary explanation for the absence of a program effect centers on the unit of analysis used for the program. The census block group is too large a geographic unit of analysis to achieve the kind of targeted and focused interventions that lead to positive crime‐prevention outcomes.

Neighborhood poverty and racial differences in ESRD incidence.

Poverty is associated with increased risk of ESRD, but its contribution to observed racial differences in disease incidence is not well-defined. To explore the contribution of neighborhood poverty to racial disparity in ESRD incidence, we analyzed a combination of US Census and ESRD Network 6 data comprising 34,767 patients that initiated dialysis in Georgia, North Carolina, or South Carolina between January 1998 and December 2002. Census tracts were used as the geographic units of analysis, and the proportion of the census tract population living below the poverty level was our measure of neighborhood poverty. Incident ESRD rates were modeled using two-level Poisson regression, where race, age and gender were individual covariates (level 1), and census tract poverty was a neighborhood covariate (level 2). Neighborhood poverty was strongly associated with higher ESRD incidence for both blacks and whites. Increasing poverty was associated with a greater disparity in ESRD rates between blacks and whites, with the former at greater risk. This raises the possibility that blacks may suffer more from lower socioeconomic conditions than whites. The disparity persisted across all poverty levels. The reasons for increasingly higher ESRD incidence among US blacks as neighborhood poverty increases remain to be explained.

Environmental Justice Analysis

This research focuses on three major challenges of incorporating environmental justice into metropolitan transportation planning. The data needed are compared with the data currently available on the spatial distributions of race and income, the spatial distributions of trip ends, trip tables, network performance, and cost estimates of improvements. Several conflicting definitions of equity are offered, as are applications for each within the context of environmental justice. The importance of choosing a correct unit of analysis is discussed, with particular emphasis on how the geographic unit of analysis is a poor proxy for the group unit, which is theoretically required, as the analysis's purpose is to compare performance measures across groups. The primary goal of this paper is to explore challenging topics such as these raising questions and concerns. The answers to the questions raised will differ depending on each implementing agency's objectives and resources.

The relationship between land use and intrazonal trip making behaviors: Evidence and implications

This paper addresses the relationship between land use, destination selection, and travel mode choice. Specifically, it focuses on intrazonal trips, a sub-category of trip making where both trip origin and trip destination are contained in the same geographic unit of analysis, using data from the 1994 Household Activity and Travel Diary Survey conducted by Portland Metro. Using multinomial logit and binary logistic models to measure travel mode choice and decision to internalize trips, the evidence supports the conclusions that (1) intrazonal trips characteristics suggest mode choice for these trips might be influenced by urban form, which in turn affects regional trip distribution; (2) there is a threshold effect in the ability of economic diversity/mixed use to alter travel behavior; and (3) greater emphasis to destinations within the area where an individual’s home is located needs to be given in trip distribution models.

On Improving the Conceptual Foundations of International Marketing Research

International marketing research plays a vital role as firms expand globally. Yet limited attention has been paid to the conceptual underpinnings of research needed to guide expansion. This article focuses on these issues and specifically examines the conceptual framework that guides research, the geographic units of analysis, and the constructs. The authors suggest two alternative approaches to organizing cross-cultural research: the adapted etic and the linked emic.

Implementation of an Internet-based Geographic Information System

Increasingly, Web-based data dissemination systems are being used to provide public health information. This article describes Florida's experience in augmenting a Web-based data query system, Florida CHARTS, with a geographic information system component. As with any systems development, users' needs guide the product. With a focus on community health assessment and improvement planning, several methods of data display have been established. A variety of issues are explored including the impact of small numbers of events on data display and data confidentiality, the selection of geographic units of analysis, and techniques for geographically coding data.

On the use of ZIP codes and ZIP code tabulation areas (ZCTAs) for the spatial analysis of epidemiological data

BackgroundWhile the use of spatially referenced data for the analysis of epidemiological data is growing, issues associated with selecting the appropriate geographic unit of analysis are also emerging. A particularly problematic unit is the ZIP code. Lacking standardization and highly dynamic in structure, the use of ZIP codes and ZIP code tabulation areas (ZCTA) for the spatial analysis of disease present a unique challenge to researchers. Problems associated with these units for detecting spatial patterns of disease are explored.ResultsA brief review of ZIP codes and their spatial representation is conducted. Though frequently represented as polygons to facilitate analysis, ZIP codes are actually defined at a narrower spatial resolution reflecting the street addresses they serve. This research shows that their generalization as continuous regions is an imposed structure that can have serious implications in the interpretation of research results. ZIP codes areas and Census defined ZCTAs, two commonly used polygonal representations of ZIP code address ranges, are examined in an effort to identify the spatial statistical sensitivities that emerge given differences in how these representations are defined. Here, comparative analysis focuses on the detection of patterns of prostate cancer in New York State. Of particular interest for studies utilizing local, spatial statistical tests, is that differences in the topological structures of ZIP code areas and ZCTAs give rise to different spatial patterns of disease. These differences are related to the different methodologies used in the generalization of ZIP code information. Given the difficulty associated with generating ZIP code boundaries, both ZIP code areas and ZCTAs contain numerous representational errors which can have a significant impact on spatial analysis. While the use of ZIP code polygons for spatial analysis is relatively straightforward, ZCTA representations contain additional topological features (e.g. lakes and rivers) and contain fragmented polygons that can hinder spatial analysis.ConclusionCaution must be exercised when using spatially referenced data, particularly that which is attributed to ZIP codes and ZCTAs, for epidemiological analysis. Researchers should be cognizant of representational errors associated with both geographies and their resulting spatial mismatch, especially when comparing the results obtained using different topological representations. While ZCTAs can be problematic, topological corrections are easily implemented in a geographic information system to remedy erroneous aggregation effects.

Is Region of Country a Useful Variable for Child Health Studies?

In their article “The Health Status of Southern Children: A Neglected Regional Disparity” (in this month's Pediatrics electronic pages ), Goldhagen et al1 have raised the intriguing question of whether US region is a significant factor for child health outcomes. Although much attention has been given to contextual influences on health,2–4 most studies have considered local contextual effects such as neighborhood characteristics.5 Few have considered region as a contextual level.2,6 Therefore, Goldhagen et al's conclusion that region is a stronger predictor of poor outcomes than other variables commonly used is quite remarkable. A careful examination of their methods is in order before their recommended research agenda is undertaken. We have 2 levels of concern: the general approach to the definition of health regions and a specific concern about the geographic unit of analysis. The definition of geographic regions for health studies can be achieved either by an impartial exploration of the geographic distribution of health statistics or through historical, sociocultural, or policy-relevant considerations. Goldhagen et al frame their article as an examination of the South, which suggests a preference for the latter approach. This focus might stem from an interest in the legacies of slavery or in current-day clustering of state policies and funding for public health and health care. Yet their methods are primarily an exploration of health statistics. They mapped the child health index (CHI) and identified the Deep South based on the revealed geographic distribution. Their methods for selecting member states are not precisely explained, but it seems that state selection was influenced somewhat by a desire to achieve a contiguous Deep South. Nevertheless, the CHI and its components were the variables used to define regions. To confirm the validity of the CHI-defined Deep South, they contrasted it with other … Address correspondence to Mark F. Guagliardo, PhD, Center for Health Services and Community Research, Children's National Medical Center, 111 Michigan Ave NW, Washington, DC 20010. E-mail: mguaglia{at}cnmc.org

Three (marginal?) questions regarding convergence

This paper focuses on three (marginal?) questions surrounding the analysis of economic convergence and uses Spanish provinces as a means of illustration. The three questions in hand are as follows. Given that the geographical units of analysis are usually quite different in economic size, is the weighting of economic units relevant in convergence analysis? The average per capita income of a given region, or country, is the first moment in the distribution of income, but what about the second moment, inequality, have we converged in inequality? An aggregate welfare index must take into account, at least, the evolution of the first two moments of the distribution of income, and so does the adjustment for inequality make important differences in the evolution of average per capita income? The answer to the first two questions is yes, but to the third it is clearly no.

Examining geographic patterns of mortality: The Atlas of mortality in small areas in Spain (1987-1995)

Small-area mortality atlases have been demonstrated to be a useful tool for both showing general geographical patterns in mortality data and identifying specific high-risk locations. In Spain no study has so far systematically examined geographic patterns of small-area mortality for the main causes of death. This paper presents the main features, contents and potential uses of the Spanish Atlas of Mortality in small areas (1987-1995). Population data for 2,218 small areas were drawn from the 1991 Census. Aggregated mortality data for 14 specific causes of death for the period 1987-1995 were obtained for each small area. Empirical Bayes-model-based estimates of age-adjusted relative risk were displayed in small-area maps for each cause/gender/age group (0-64 or 65 and over) combination using the same range of values (i.e. septiles) and colour schemes. The 'Spanish Atlas of Mortality' includes multiple choropleth (area-shaded) small-area maps and graphs to answer different questions about the data. The atlas is divided into three main sections. Section 1 includes the methods and comments on the main maps. Section 2 presents a two-page layout for each leading cause of death by gender including 1) a large map with relative risk estimates, 2) a map that indicates high- and low-risk small areas, 3) a graph with median and interquartile range of relative risk estimates for 17 large regions of Spain, and 4) relative-risk maps for two age groups. Section 3 provides specific information on the geographical units of analysis, statistical methods and other supplemental maps. The 'Spanish Atlas of Mortality' is a useful tool for examining geographical patterns of mortality risk and identifying specific high-risk areas. Mortality patterns displayed in the atlas may have important implications for research and social/health policy planning purposes.

Outlets, drinking and driving: a multilevel analysis of availability.

This study examines the degree to which the physical availability of alcohol as measured by outlet densities is related to self-reported individual drinking patterns, preferred drinking location, as well as both driving after drinking (DAD) and driving while intoxicated (DWI). Data from 7,826 drinkers were obtained from a general-population telephone survey of 1,353 zip code areas in California. Measures of individual alcohol consumption included drinking frequency, drinks per occasion and variance in quantities consumed per occasion. Preferred drinking locations included bars, restaurants and the homes of drinkers and of their friends. DAD was defined as driving a motor vehicle within 4 hours of having one or more alcoholic drinks, and DWI was defined as driving after having too much to drink and drive safely. Geographic measures of outlet densities were obtained for bars, restaurants and off-premises establishments, using zip codes as geographic units of analysis. Hierarchical linear modeling was used to relate outlet densities within and surrounding respondents' area of residence to respondents' drinking and to respondents' drinking and driving. Whereas restaurant densities were directly related to greater drinking frequencies and DAD, bar densities were inversely related to DAD. There were no direct effects of drinking patterns on drinking and driving. Drinking and driving was strongly related to drinking location preference (e.g., bars and restaurants) only when considered simultaneously with individual drinking patterns, particularly drinking frequency. Increased restaurant density is strongly related to higher rates of both self-reported driving after drinking and drinking frequency. The strongest influence on both driving after drinking and driving while intoxicated is preferred drinking location considered together with individual drinking patterns. Outlet density and preferred drinking location when considered together with individual drinking patterns support driving after drinking and thereby increase the potential for alcohol-related accidents.

Geo-Additive Models of Childhood Undernutrition in Three Sub-Saharan African Countries

We investigate the geographical and socioeconomic determinants of childhood undernutrition in Malawi, Tanzania, and Zambia, three neighboring countries in Southern Africa using the 1992 Demographic and Health Surveys. We estimate models of undernutrition jointly for the three countries to explore regional patterns of undernutrition that transcend boundaries, while allowing for country-specific interactions. We use semiparamtetric models to flexibly model the effects of selected socioeconomic covariates and spatial effects. Our spatial analysis is based on a flexible geo-additive model using the district as the geographic unit of analysis, which allows to separate smooth structured spatial effects from random effects. Inference is fully Bayesian and uses recent Markov Chain Monte Carlo techniques. While the socioeconomic determinants generally confirm what is known in the literature, we find important non-linear effects of some covariates. Also, we find distinct residual spatial patterns that are not explained by the socioeconomic determinants. In Particular, there appears to be a belt running from Southern Tanzania to Northeastern Zambia which exhibits much worse undernutrition, even after controlling for socioecononomic effects. These effects do transcend borders, but to a varying degree. These findings have important implications for targeting policy as well as the search for left-out variables that might account for these residual spatial patterns.

A Subnational Analysis of Japanese Direct Investment in Canada

AbstractThis study examines longitudinal aspects of Japanese foreign direct investment in Canada. In looking at the longitudinal aspects, the focus was on a descriptive analysis of entry and exit rates and on an econometric analysis of the determinants of subsidiary survival and exit. In these analyses, we find that exit rates are related to subsidiary‐level variables such as business size, expatriate employment levels, equity‐ownership levels, and entry mode. The sector and region in which the investments are made is also related to subsidiary survival, with manufacturing‐sector subsidiaries located in Ontario being the least likely to exit. The results of our study suggest that region and industry interact, both to draw investment to a region and to influence the likeli‐hood of survival of foreign‐owned businesses. Further‐more, the focus on regional issues for Canada shows that even within a small open economy, subnational (interprovincial) variance can have important effects on the characteristics and performance of foreign direct investment.RésuméLa présente étude porte sur l'évolution des investissements directs japonais à l'étranger, réalisés au Canada. De façon plus précise, cette recherche s'intéresse, sur une base longitudinale, à l'analyse descriptive des taux d'entrée et de sortie ainsi qu'à l'analyse économétrique des facteurs expliquant la survie ou la sortie de filiales japonaises. A la lumière de ces analyses, il ressort que les taux de sortie sont influencés par certaines caractéristiques des filiales telles que la taille, la proportion d'expatriés, la part du capital‐action et le mode d'entrée. Le secteur et la région où l'investissement s'effectue influencent également les chances de survie d'une filiale; la probabilité la plus faible de quitter le pays appartiendrait aux filiales manufacturières situées en Ontario. Les résultats de l'étude suggèrent que la région et l'industrie interagissent de façon à attirer les investissements dans une région donnée et à influencer les chances de survie de compagnies appartenant à des intérěts étrangers. Ces résultats sur les disparités régionales du Canada suggèrent que, měme à l'intérieur d'une économie de marché restreinte, la variance sous‐nationale (ou interprovinciale) peut avoir d'importantes répercussions sur les caractéristiques et la performance des investissements directs à l'étranger.

The contested terrain of environmental justice research: community as unit of analysis

Social scientists have entered the debate over the environmental inequities facing the poor in general, and communities of color in particular. Crucial to their empirical studies is the operational definition of “community” as a unit of analysis. Different operationalizations of community exist, leading to divergent conclusions about the extent of the problem. Earlier research concluded that inequities were national in scope, while later studies found little evidence to support the previous research. This paper examines three general ways in which community has been framed as a geographical unit of analysis in environmental justice research: (1) as a neighborhood (a place of cultural identity); (2) as part of a political jurisdiction (county, city, etc.); and (3) as approximated by data constructs (like zip code areas and census tracts). The paper discusses several theoretical and methodological issues involved in operationally defining an appropriate unit, or units, of analysis for research on environmental inequity.

Deviation from the carrying capacity for physicians and growth rate of physician supply: The Taiwan case

This study applies the theory of carrying capacity to examine the effects of market forces on the location pattern of physicians in Taiwan between 1974 and 1982. The data for the analysis were collected from governmental publications. The township was selected as the geographic unit of analysis. By using a regression model of physician supply, this study developed a proxy for physician carrying capacity and a deviation indicator to classify townships as attractive or unattractive. The results of this study indicate that: (1) within attractive townships, the greater the deviation from physician carrying capacity, the faster the growth rate of the physician-population ratio; (2) the overall pattern of the growth rate is quite similar across different sizes of townships; and (3) due to a loss of population, unattractive townships do not necessarily have the lowest growth rates of the physician-population ratio even though they gain few physicians. This study thus concludes that market forces are powerful in determining the physician distribution.