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Identifying factors associated with the spatial distribution of disease

Dirk U. Pfeiffer, Timothy P. Robinson, Mark Stevenson, Kim B. Stevens, David J. Rogers, and Archie C. A. Clements

in Spatial Analysis in Epidemiology

This chapter presents analytical techniques of regression and discrimination as a means of quantifying the effect of a set of explanatory variables on the spatial distribution of a particular ... More

This chapter presents analytical techniques of regression and discrimination as a means of quantifying the effect of a set of explanatory variables on the spatial distribution of a particular outcome. The chapter is divided into four sections. The first outlines the principles of linear, Poisson, and logistic regression in order to provide a background to the material presented later in the chapter. The second section discusses the options available to identify and account for spatial dependency in data when modelling. The third section reviews the common analytical techniques available for dealing with the three major spatial data types (area, point, and continuous data), and the fourth deals with discriminant analysis.Less

Spatial distribution

Stephen M. Evans

in Quantitative Methods in Neuroscience: A Neuroanatomical Approach

The human brain is made up of an ordered three-dimensional array of smaller units, for example, the vertical and horizontal organization of neurons in the cerebral cortex. Knowledge of the structural ... More

The human brain is made up of an ordered three-dimensional array of smaller units, for example, the vertical and horizontal organization of neurons in the cerebral cortex. Knowledge of the structural relationship of these small units should provide more insight into brain function as a whole and how it doesn't function in pathological states. This chapter describes a method that can directly measure three-dimensional point patterns from measurements done on one section. The method is based on the nucleator principle where the probability that a point in three-dimensional space is hit by the probe is known. One of the unique features of the nucleator is that in one section the three-dimensional distance can be measured from a typical point to everything else that is observable in the section. That is to say, it is possible to estimate the variation of events, in this case the number of points, as a function of distance, that is, the three-dimensional spatial distribution of the points.Less

Spatial Data: Analysis And Estimation

Steve Selvin

in Statistical Analysis of Epidemiologic Data

Spatial distributions have played a major role in the epidemiology of several diseases and are essential for the analysis of data involving exposures to environmental pollutants. This chapter ... More

Spatial distributions have played a major role in the epidemiology of several diseases and are essential for the analysis of data involving exposures to environmental pollutants. This chapter explores the process of identifying non-random spatial patterns of disease, and introduces several important statistical techniques (nearest-neighbor analysis, randomization tests, and bootstrap analytic methods) that can be applied to a wide range of other kinds of data.Less

Adverse Geography and Differences in Welfare in Peru

Ravi Kanbur and Anthony J. Venables

in Spatial Inequality and Development

In Peru, a country with an astonishing variety of different ecological areas, with 84 different climate zones and landscapes, with rainforests, high mountain ranges and dry deserts, the geographical ... More

In Peru, a country with an astonishing variety of different ecological areas, with 84 different climate zones and landscapes, with rainforests, high mountain ranges and dry deserts, the geographical context may not be all that matters, but it could be very significant in explaining regional variations in income and poverty. The major question the authors try to answer is: what role do geographic variables, both natural and man-made, play in explaining per capita expenditure differentials across regions within Peru? How have these influences changed over time, through what channels have they been transmitted, and has access to private and public assets compensated for the effects of an adverse geography?Less

Spatial Analyses of Obesity and Poverty

Adam Drewnowski

in Insecurity, Inequality, and Obesity in Affluent Societies

Obesity in the United States is a socio-economic issue. Recent advances in geographic information system methodology can provide a better understanding of the impact of neighbourhood deprivation on ... More

Obesity in the United States is a socio-economic issue. Recent advances in geographic information system methodology can provide a better understanding of the impact of neighbourhood deprivation on access to healthy foods, diet quality and selected health outcomes. Whereas state-level Centers for Disease Control maps are still best known, newer approaches have mapped obesity at different levels of geographic aggregation: county, political district, zip code or census tract. This chapter examines data from the new Seattle Obesity Study, which permits the mapping of dietary behaviours and health outcomes at the property parcel tax level – the finest level of geographic resolution possible. Analysis suggests that food-consumption patterns also show a spatial distribution, broadly following the geographic distribution of wealth and social class.Less

Patterns of Biodiversity at Fine and Small Spatial Scales

Matty P. Berg

in Soil Ecology and Ecosystem Services

The biodiversity in fertile soil is mind-boggling. How can a large collection of species that potentially competes for the same resources coexist on a small spatial scale from a few centimetres to a ... More

The biodiversity in fertile soil is mind-boggling. How can a large collection of species that potentially competes for the same resources coexist on a small spatial scale from a few centimetres to a few meters? This riddle of soil biodiversity has occupied ecologists for many decades. Spatial heterogeneity in essential resources for soil organisms is a part of solving this puzzle. This chapter describes the spatial distribution of dominant and important soil organisms at the fine to small scale, and discusses the scale-relevant drivers that determine the patchy distributions of soil organisms. The heterogeneous distribution of species, both horizontally as well as vertically, will subsequently result in a patch distribution of soil functions, (i.e., nitrification and denitrification) as soil processes are critically dependent on the structure of soil communities and on functionally influential species. The chapter concludes with the observation that spatial scales are nested within each other, and that the drivers which operate at the various scales interact and together determine species distribution. This observation calls for the integration of spatial scales to understand how heterogeneity, and disturbances that operate at a hierarchy of scales, affect species distributions and soil processes.Less

Regions, Globalization, and the Knowledge Economy: The Issues Stated

John H. Dunning

in Regions, Globalization, and the Knowledge-Based Economy

Offers an analytical framework for evaluating the implications of recent economic events on the spatial distribution of economic activities, and of the role played by multinational enterprises (MNEs) ... More

Offers an analytical framework for evaluating the implications of recent economic events on the spatial distribution of economic activities, and of the role played by multinational enterprises (MNEs) and cross‐border coalitions of firms on the international and intranational division of labour. In particular, it is concerned with the parallel, yet apparently antithetical, forces towards the geographical dispersion of asset‐augmenting and asset‐exploiting activities, and the concentration of such activities in limited spatial areas—what has been referred to as the paradox of ‘sticky places within slippery space’.Less

Producing an Improved Geographic Profile of Poverty: Methodology and Evidence from Three Developing Countries

Gabriel Demombynes, Chris Elbers, Jean O. Lanjouw, Peter Lanjouw, Johan Mistiaen, and Berk Özler

in Growth, Inequality, and Poverty: Prospects for Pro-poor Economic Development

This study implements a methodology for estimating poverty in Ecuador, Madagascar, and South Africa, at levels of disaggregation that to date have not generally been available. The methodology is ... More

This study implements a methodology for estimating poverty in Ecuador, Madagascar, and South Africa, at levels of disaggregation that to date have not generally been available. The methodology is based on a statistical procedure to combine household survey data with population census data, imputing into the latter, a measure of per capita consumption from the former. The countries have few similarities; yet, the study demonstrates that in all three, the poverty estimates produced from census data are both plausible and satisfactorily precise. The study illustrates how the resulting poverty estimates can be represented in maps, thereby conveying much information about the magnitude of poverty across localities, as well as the precision of estimates, in a way that can be readily absorbed by non‐technical audiences.Less

Topics in Modern Cosmology

P. J. E. Peebles

in Principles of Physical Cosmology

This chapter recounts the discovery that the spiral nebulae are galaxies of stars and coequals of the Milky Way, which led to the exploration of a new level in the hierarchy of structure in the ... More

This chapter recounts the discovery that the spiral nebulae are galaxies of stars and coequals of the Milky Way, which led to the exploration of a new level in the hierarchy of structure in the physical universe called the realm of the spiral nebulae. It details how cosmology has grown to include the study of other systems, such as the radiation backgrounds and the gas cloud, but common luminous galaxies comparable to the Milky Way remain the centerpiece. It also highlights some of the ways people came to see that the spiral nebulae as island universes of stars and discusses some elements of the systematics of the structures and spatial distribution of the galaxies. The chapter reviews the luminosity of the Milky Way galaxy that had been estimated from star counts and statistical estimates of star distances by 1920. It mentions Ernst Öpik, who put the ratio of the mass to luminosity.Less

Analytical solution of the elastic transport equation

Melvin Lax, Wei Cai, and Min Xu

in Random Processes in Physics and Finance

An example of a random process is the propagation of a particle (or photons, or acoustic wave) in a turbid medium, where particles undergo multiple scattering by randomly distributed scatterers in ... More

An example of a random process is the propagation of a particle (or photons, or acoustic wave) in a turbid medium, where particles undergo multiple scattering by randomly distributed scatterers in the medium. The kinetic equation governing particle propagation is the classic Boltzmann transport equation, which is also called the radiative transfer equation in the case of light propagation. The search for an analytical solution of the time-dependent elastic Boltzmann transport equation has lasted for many years. This chapter considers the problem of the classic elastic Boltzmann transport equation based on cumulant expansion. An analytical expression for cumulants of the spatial distribution of particles at any angle and time, exact up to an arbitrarily high order, is derived in an infinite uniform scattering medium. Up to the second order, a Gaussian approximation of the distribution function for the Boltzmann transport equation is obtained, with exact average center and exact half-width with time.Less

The Sampling Programme and the Measurement and Description of Dispersion

Peter A. Henderson

in Southwood's Ecological Methods

The steps required during the planning of a sampling campaign are described. The time of sampling within the life-cycle, the size of the sampling unit, number of samples, and distribution of the ... More

The steps required during the planning of a sampling campaign are described. The time of sampling within the life-cycle, the size of the sampling unit, number of samples, and distribution of the samples is discussed. Statistical aspects of sample design are introduced, including the normal distribution, the negative binomial distribution and species dispersal, Taylor’s power law, and aggregation indices. Pattern analysis, SADIE spatial analysis, and crowding indices are described. Nearest-neighbour and closest-neighbour techniques to estimate population density are reviewed. Sequential sampling methodologies and software are described. Presence–absence sampling and binomial data analysis are described.Less

Anatomy of the nervous system Anatomy of the nervous system

Malcolm Burrows

in The Neurobiology of an Insect Brain

The synapses that a neuron makes can be described in terms of their spatial distribution, likely transmitters, and contacts with other known neurons. The use of antibodies raised against particular ... More

The synapses that a neuron makes can be described in terms of their spatial distribution, likely transmitters, and contacts with other known neurons. The use of antibodies raised against particular chemical components of the neurons, most frequently putative neurotransmitters and neuromodulators, can reveal the structure of individual neurons, the distribution of certain groups of somata, and patterns of neuronal projections, so giving a chemical mapping of the nervous system. Antibodies can also be used to reveal the distribution of different types of ion channels in the nervous system and even within different parts of an individual neuron. This combination of anatomical, physiological, and chemical methods allows such good characterisation of the neurons that they can often be treated as identified individuals.Less

The Ecology of Fossil Taxa through Time

Mark E. Patzkowsky and Steven M. Holland

in Stratigraphic Paleobiology: Understanding the Distribution of Fossil Taxa in Time and Space

This chapter examines the ecology of individual taxa and methods for determining how their ecology changes through time. The stratigraphic record provides the opportunity to map the spatial ... More

This chapter examines the ecology of individual taxa and methods for determining how their ecology changes through time. The stratigraphic record provides the opportunity to map the spatial distribution of fossil taxa through time, including their geographic range, environmental preference, environmental breadth, and their spatial distribution of abundance. Tracing the niche dimensions of taxa through time requires that the environmental gradients over which a taxon ranges are preserved approximately equally through time. The ecology of fossil taxa is essential for the understanding of the history of life, yet little is currently known about niche dimensions of fossil taxa and how they change through time. Thus, sequence stratigraphy provides a high-resolution time-environment framework that allows us to model and measure the niches of fossil taxa and to understand the role of environmental change in niche evolution over a range of temporal scales.Less

Proxy-based approaches in ecology and the importance of remote sensing

Nathalie Pettorelli

in The Normalized Difference Vegetation Index

This chapter begins by presenting the main challenges and consequences caused by environmental change to the world to provide a better understanding of the full potential of remote sensing in ... More

This chapter begins by presenting the main challenges and consequences caused by environmental change to the world to provide a better understanding of the full potential of remote sensing in biodiversity monitoring. It introduces the scope of remote sensing and the technical aspects of remote sensing data manipulation and interpretation. It also provides an overview of the structure of the book.Less

The Database and Our Methodology

Duncan Garrow and Chris Gosden

in Technologies of Enchantment?: Exploring Celtic Art: 400 BC to AD 100

This chapter describes how the database used in the present study was put together, looking at its main findings along with some of its biases. It then presents some initial observations about the ... More

This chapter describes how the database used in the present study was put together, looking at its main findings along with some of its biases. It then presents some initial observations about the spatial and temporal distribution of Celtic art, as such trends were fundamental in orienting how the analyses developed. The nature of decoration is central to the contention that Celtic art represented works of quality, as opposed to the quantity emphasized in the Late Bronze Age. The chapter also make some initial observations about the construction of decoration and its changes over time, leading to a consideration of what sorts of impacts it might have had.Less

The Changing Cultural Landscape of the Lower St. Joseph River Valley

Mark Hoock, Allison M. Hoock, and Michael S. Nassaney

Michael S. Nassaney and Michael S. Nassaney (eds)

in Fort St. Joseph Revealed: The Historical Archaeology of a Fur Trading Post

Archaeological studies conducted under the auspices of the Fort St. Joseph Archaeological Project have focused on material remains in the St. Joseph River valley in Niles, Michigan. Material remains ... More

Archaeological studies conducted under the auspices of the Fort St. Joseph Archaeological Project have focused on material remains in the St. Joseph River valley in Niles, Michigan. Material remains indicate that human groups exploited resources and established settlements throughout the area, and that, in the context of local and regional political economic relations, those settlements shifted in response to changes in resources availability and alliance formation. This chapter examines the spatial distribution of Euro-American and Native American sites in the lower St. Joseph River Valley during the periods ranging from immediately prior, to during, and to after the occupation of Fort St. Joseph. Through the use of geographic information systems (GIS), the authors monitored changes in settlement patterns as they related to the establishment and abandonment of this French colonial outpost.Less