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Geographic Space (geographic + space)
Selected AbstractsASSESSING THE EFFECTS OF MASS INCARCERATION ON INFORMAL SOCIAL CONTROL IN COMMUNITIESCRIMINOLOGY AND PUBLIC POLICY, Issue 2 2004JAMES P. LYNCH Research Summary: This paper reviews and evaluates the existing (and limited) evidence that increases in incarceration have affected the ability of residential neighborhoods to perform their traditional social control functions. It suggests that, although comparatively weak, the evidence points to the increases in the level and clustering in social and geographic space of incarceration as contributing to changes in the social organization of affected communities by weakening family formation, labor force attachments, and patterns of social interaction among residents. At the same time, however, the paper does find support for the contention that incarceration leads to reductions in crime in affected communities. Policy Implications: To the extent that mass incarceration disrupts patterns of social interaction, weakens community social organization, and decreases the stigma of imprisonment, its longer-run effects may be to reduce its effectiveness. [source] Mapping convergence points in the initial emergency response to 9/11,DISASTERS, Issue 4 2009Christine A. Bevc In response to extreme events, researchers have recognised the convergence of volunteers, emergency responders, and other individuals and organisations. In 2000, geographer Paul Routledge presented the concept of convergence spaces as a theoretical means to explain social movements. In applying this concept, this paper explores the geographic space in which organisations and individuals converged immediately following the 11 September 2001 attacks on the World Trade Center. The paper begins to answer the question of whether there were in fact any patterns of convergence among the locations utilised by organisations responding to the attacks. Using data collected from field documents, these geographic locations are mapped over 12 days to help identify possible patterns of clustering. Results of this analysis will begin to provide researchers, policy makers and practitioners with a better understanding of how emergency response evolves geographically following an event. [source] Investigating Global and Local Categorical Map Configuration Comparisons Based on Coincidence MatricesGEOGRAPHICAL ANALYSIS, Issue 2 2009T. K. Remmel The simple and intuitive nature of the coincidence matrix has not only made it the current "gold standard" for accuracy assessment (based on a sample of map pixels), but also a common tool for describing difference between two categorical maps (when all pixels are enumerated). It is this latter case of map comparison that this article explores. Coincidence matrices, although providing significant information regarding thematic agreement between two categorical maps (composition), can lack significantly in terms of conveying information about differences or similarities in the spatial arrangement (configuration) of those map categories in geographic space. This article introduces means for distilling the available configuration information from a coincidence matrix while demonstrating some simple categorical map comparisons. Specifically, while the coincidence matrix summarizes per-pixel compositional persistence or change, the introduced technique further quantifies the global and local configurational uncertainty between compared maps. I demonstrate how this quantification of configurational uncertainty can be used to gauge which thematic mismatch types are most significant and how to measure/present local configurational uncertainty in a spatial context. Implementation is through a straightforward mathematical algorithm in R that is illustrated by several examples. La sencillez y características las matrices de confusión (tablas de contingencia o de error) no sólo la ha convertido en (1) el estándar por excelencia para la evaluación de confiabilidad (veracidad o validez) de mapas temáticos en escala nominal (en base de una muestra de pixeles en un mapa), sino también en (2) una herramienta común para describir la diferencia entre dichos mapas (cuando todos los pixeles son tomados en cuenta). Este segundo uso de las matrices de confusión es el tema explorado por el presente artículo. A pesar de proporcionar información importante acerca de la confiabilidad temática entre dos mapas de categorías nominales (composición), las matrices de confusión sufren de limitaciones importantes cuando el objetivo es extraer información acerca del patrón o arreglo espacial (configuración) de las categorías del mapa. El presente artículo presenta herramientas para destilar la información de configuración espacial disponible a partir de una matriz de confusión, y al mismo tiempo, ilustra algunas comparaciones entre mapas de categorías nominales. En términos más concretos, la matriz de confusión resume la persistencia o cambio en la composición a nivel de cada pixel. La nueva técnica presentada en este estudio incluye además la cuantificación de la incertidumbre en la configuración de los mapas comparados. El autor demuestra cómo esta cuantificación puede ser utilizada para darse una idea de cuáles tipos de errores temáticos son más importantes, y cómo se puede medir e ilustrar la incertidumbre de la configuración local en el contexto espacial. La implementación del método se realiza a través de un algoritmo matemático sencillo en lenguaje R, el mismo que es ilustrado con varios ejemplos. [source] Contiguity Constraints for Single-Region Site Search ProblemsGEOGRAPHICAL ANALYSIS, Issue 4 2000Thomas J. Cova This paper proposes an explicit set of constraints as a general approach to the contiguity problem in site search modeling. Site search models address the challenging problem of identifying the best area in a study region for a particular land use, given that there are no candidate sites. Criteria that commonly arise in a search include a site's area, suitability, cost, shape, and proximity to surrounding geographic features. An unsolved problem in this modeling arena is the identification of a general set of mathematical programming constraints that can guarantee a contiguous solution (site) for any 0,1 integer-programming site search formulation. The constraints proposed herein address this problem, and we evaluate their efficacy and efficiency in the context of a regular and irregular tessellation of geographic space. An especially efficient constraint form is derived from a more general form and similarly evaluated. The results demonstrate that the proposed constraints represent a viable, general approach to the contiguity problem. [source] Spatial analysis of taxonomic and genetic patterns and their potential for understanding evolutionary historiesJOURNAL OF BIOGEOGRAPHY, Issue 11 2004Sophia A. Bickford Abstract Aim, The aim of this research is to develop and investigate methods for the spatial analysis of diversity based on genetic and taxonomic units of difference. We use monophyletic groups of species to assess the potential for these diversity indices to elucidate the geographical components of macro-scaled evolutionary processes. Location, The range occupied by Pultenaea species in temperate and sub-tropical eastern Australia, extending from western South Australia (133° E,32° S) to Tasmania (146° E,43° S) to coastal central Queensland (148° E,20° S). Methods, We applied a series of both spatially explicit and spatially implicit analyses to explore the nature of diversity patterns in the genus Pultenaea, Fabaceae. We first analysed the eastern species as a whole and then the phylogenetic groups within them. We delineated patterns of endemism and biotic (taxon) regions that have been traditionally circumscribed in biogeographical studies of taxa. Centres of endemism were calculated using corrected weighted endemism at a range of spatial scales. Biotic regions were defined by comparing the similarity of species assemblages of grid cells using the Jaccard index and clustering similar cells using hierarchical clustering. On the basis that genetically coherent areas were likely to be more evolutionary informative than species patterns, genetic indices of similarity and difference were derived. A matrix of similarity distances between taxa was generated based on the number of shared informative characters of two sections of trnL-F and ndhF chloroplast nuclear regions. To identify genetically similar areas, we clustered cells using the mean genetic similarities of the species contained within each pair of cells. Measures of the mean genetic similarity of species in areas were delineated using a geographically local multi-scalar approach. Resultant patterns of genetic diversity are interpreted in relation to theories of the evolutionary relationships between species and species groups. Results, Centres of Pultenaea endemism were defined, those of clades 1 congruent with the spatially separated centres of clades 2 and 3. The taxonomic classification analysis defined cells with shared groups of species, which in some cases clustered when plotted in geographic space, defining biotic regions. In some instances the distribution of biotic regions was congruent with centres of endemism, however larger scale groupings were also apparent. In clade 1 one set of species was replaced by another along the extent of the range, with some connectivity between some geographically disjunct regions due to the presence of widespread species. In the combined analysis of clade 2 and 3 species the major biotic (taxonomic) groups with geographic coherence were defined by species in the respective clades, representing the geographic separation of these clades. However distinctive biotic regions within these main groupings of clades 2 and 3 were also apparent. Clustering cells using the mean genetic similarities of the species contained within each pair of cells indicated that some of the taxonomically defined biotic boundaries were the result of changes in composition of closely related species. This was most apparent in clades 1 and 2 where most cells were highly genetically similar. In clade 3 genetically distinct groups remained and were in part defined by sister taxa with disjunct distributions. Gradients in mean genetic similarity became more apparent from small to larger scales of analysis. At larger scales of analysis, regions of different levels of genetic diversity were delineated. Regions with highest diversity levels (lowest level of similarity) often represented regions where the ranges of phylogenetically distinctive species intergraded. Main conclusions, The combined analysis of diversity, phylogeny and geography has potential to reveal macro-scaled evolutionary patterns from which evolutionary processes may be inferred. The spatial genetic diversity indices developed in this study contribute new methods for identifying coherent evolutionary units in the landscape, which overcome some of the limitations of using taxonomic data, and from which the role of geography in evolutionary processes can be tested. We also conclude that a multiple-index approach to diversity pattern analysis is useful, especially where patterns may be the result of a long history of different environmental changes and related evolutionary events. The analysis contributes to the knowledge of large-scale diversity patterns of Pultenaea which has relevance for the assessment of the conservation status of the genus. [source] Effects of environmental variables on fish feeding ecology: implications for the performance of baited fishing gear and stock assessmentJOURNAL OF FISH BIOLOGY, Issue 6 2004A. W. Stoner The effectiveness of baited fishing gear ultimately depends upon behaviour of the target species , activity rhythms, feeding motivation, and sensory and locomotory abilities. While any environmental parameter that mediates feeding or locomotion can have an important influence on the active space presented by the bait and fish catchability, few biologists have considered how such variation in behaviour might affect catch per unit effort (CPUE) and the resultant stock abundance estimates or population parameters. This review reveals that environment-related variation in feeding behaviour can act through four different mechanisms: metabolic processes, sensory limitations, social interactions and direct impacts. Water temperature, light level, current velocity and ambient prey density are likely to have largest effects on fish catchability, potentially affecting variation in CPUE by a factor of ten. Feeding behaviour is also density-dependent, with both positive and negative effects. Over time and geographic space a target species can occupy wide ranges of environmental conditions, and in certain cases, spatial and temporal variation in feeding biology could have a larger impact on CPUE than patterns of abundance. Temperature, light and current can be measured with relative facility and corrections to stock assessment models are feasible. Making corrections for biological variables such as prey density and bait competitors will be more difficult because the measurements are often not practical and relationships to feeding catchability are more complex and poorly understood. There is a critical need for greater understanding of how environmental variables affect feeding-related performance of baited fishing gear. A combination of field observations and laboratory experiments will be necessary to parameterize stock assessment models that are improved to accommodate variation in fish behaviour. Otherwise, survey data could reveal more about variation in behaviour than abundance trends. [source] Introduction to "Moral Economies, State Spaces, and Categorical Violence"AMERICAN ANTHROPOLOGIST, Issue 3 2005K. SIVARAMAKRISHNAN Guest Editor By studying and writing about social revolutions and popular protest, James Scott has provided anthropologists and social theorists with a wide-ranging analytical vocabulary for speaking about peace and its inseparable twin,violence. His particular area of expertise has been the arts of repressive peace, and the artfulness of those who elude or defy such silencing technologies. The publication of The Moral Economy of the Peasant in 1976 initiated the first interactions between Scott's unique brand of political theory and anthropology in the shared topical space of peasant studies and the shared geographic space of Asian studies. The authors of this "In Focus" have assembled this special collection to celebrate and evaluate those and subsequent interactions covering a quarter of a century and spanning the publication of at least three other books: Weapons of the Weak (1985), Domination and the Arts of Resistance (1990), and Seeing Like a State (1998). [source] Preliminary Highway Design with Genetic Algorithms and Geographic Information SystemsCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2000Jyh-Cherng Jong A method that integrates geographic information systems (GIS) with genetic algorithms (GAs) for optimizing horizontal highway alignments between two given end points is presented in this article. The proposed approach can be used to optimize alignments in highly irregular geographic spaces. The resulting alignments are smooth and satisfy minimum-radius constraints, as required by highway design standards. The objective function in the proposed model considers land-acquisition cost, environmental impacts such as wetlands and flood plains, length-dependent costs (which are proportional to the alignment length), and user costs. A numerical example based on a real map is employed to demonstrate application of the proposed model to the preliminary design of horizontal alignments. [source] | ||||||||||