Spatially Lagged Choropleth Display

Choropleth display of spatial information is a fundamental feature of mapping and geographic information system technologies. There has long been a desire to impart some spatial influence in the class selection and delineation process of choropleth display. This paper presents an approach for representing the spatial influence of neighboring areas in the creation of choropleth classes. The usefulness of this approach is explored using suburb level crime statistics for Brisbane, Australia.

Optimizing public transit quality and system access: the multiple-route, maximal covering/shortest-path problem

Public transit service is a promising travel mode because of its potential to address urban sustainability. However, current ridership of public transit is very low in most urban regions -- particularly those in the United States. Low transit ridership can be attributed to many factors, among which poor service quality is key. Transit service quality may potentially be improved by decreasing the number of service stops, but this would be likely to reduce access coverage. Improving transit service quality while maintaining adequate access coverage is a challenge facing public transit agencies. In this paper we propose a multiple-route, maximal covering/shortest-path model to address the trade-off between public transit service quality and access coverage in an established bus-based transit system. The model is applied to routes in Columbus, Ohio. Results show that it is possible to improve transit service quality by eliminating redundant or underutilized service stops.

Spatial optimization for land use allocation: accounting for sustainability concerns

Land-use allocation has long been an important area of research in regional science. Land-use patterns are fundamental to the functions of the biosphere, creating interactions that have substantial impacts on the environment. The spatial arrangement of land uses therefore has implications for activity and travel within a region. Balancing development, economic growth, social interaction, and the protection of the natural environment is at the heart of long-term sustainability. Since land-use patterns are spatially explicit in nature, planning and management necessarily must integrate geographical information system and spatial optimization in meaningful ways if efficiency goals and objectives are to be achieved. This article reviews spatial optimization approaches that have been relied upon to support land-use planning. Characteristics of sustainable land use, particularly compactness, contiguity, and compatibility, are discussed and how spatial optimization techniques have addressed these characteristics are detailed. In particular, objectives and constraints in spatial optimization approaches are examined

Comparative approaches for assessing access to alcohol outlets: exploring the utility of a gravity potential approach.

BackgroundA growing body of research recommends controlling alcohol availability to reduce harm. Various common approaches, however, provide dramatically different pictures of the physical availability of alcohol. This limits our understanding of the distribution of alcohol access, the causes and consequences of this distribution, and how best to reduce harm. The aim of this study is to introduce both a gravity potential measure of access to alcohol outlets, comparing its strengths and weaknesses to other popular approaches, and an empirically-derived taxonomy of neighborhoods based on the type of alcohol access they exhibit.MethodsWe obtained geospatial data on Seattle, including the location of 2402 alcohol outlets, United States Census Bureau estimates on 567 block groups, and a comprehensive street network. We used exploratory spatial data analysis and employed a measure of inter-rater agreement to capture differences in our taxonomy of alcohol availability measures.ResultsSignificant statistical and spatial variability exists between measures of alcohol access, and these differences have meaningful practical implications. In particular, standard measures of outlet density (e.g., spatial, per capita, roadway miles) can lead to biased estimates of physical availability that over-emphasize the influence of the control variables. Employing a gravity potential approach provides a more balanced, geographically-sensitive measure of access to alcohol outlets.ConclusionsAccurately measuring the physical availability of alcohol is critical for understanding the causes and consequences of its distribution and for developing effective evidence-based policy to manage the alcohol outlet licensing process. A gravity potential model provides a superior measure of alcohol access, and the alcohol access-based taxonomy a helpful evidence-based heuristic for scholars and local policymakers

Alternate Input-Output Matrix Updating Formulations

There has been a recent resurgence of interest in biproportional adjustment methods for updating and interpreting change in matrix representations of regional structures, most commonly input-output accounts. Although the biproportional method, commonly called the RAS technique in the input-output literature, has been shown to have a number of theoretically appealing properties, various alternatives do exist. In this paper, we develop and assess empirically a number of alternatives, comparing performance and examining attributes of these adjustment methods. Two of these are sign-preserving updating methods for use when tables contain both positive and negative entries. One of these is shown to generate less information gain than Junius and Oosterhaven’s generalized RAS method which was formulated to deal with matrices with both positive and negative values. Overall, while the RAS method continues to be commonly used and its choice is often rational, alternative methods can perform as well or better along certain dimensions and in certain contexts

Exploring Micro-scale Spatiotemporal Dynamics of Restaurant Entrepreneurship with Public Open Data

Commercial activities within a city have competed to attract people, and the interactions between these activities have affected urban dynamics. Among many services, the restaurant business accounts for a significant portion of the urban economy, with spatiotemporal variations in survivability reflecting crucial signs of changes in urban structure. This study aims to identify the patterns of spatiotemporal changes in restaurants locations to deepen our understanding of urban dynamics. Studies have utilized a variety of data sources, including social media and consumer review services, but they cover relatively short periods and focus on currently operating businesses. Public open data, however, offers potential to reveal continuous changes in urban space at micro scales since it covers an entire population with individual historic records, making it complete rather than a sample. In this study, we explore newly released public open data on licenses of restaurants in Seoul, South Korea to identify spatiotemporal dynamics of commercial activities in the city using three exploratory analytics, including hot spot analysis, trends analysis of spatial clusters, and space-time scan statistics. The results show continuous temporal changes in spatial clusters of restaurants. Hot spots remain in three traditional cores of Seoul, although each cluster has shrunk over time. Moreover, suburbs have become more risky, with significant declines and more closures than expected as well as relatively shorter lifespans. This implies a concentration of restaurants in central areas, which can further economic disparities within a city. By portraying spatiotemporal changes in restaurant entrepreneurship with public open data, this study provides essential knowledge about urban dynamics informing individual and public decision making processes, particularly associated with locating new businesses

Scale and Unit Specification Influences in Harvest Scheduling with Maximum Area Restrictions

This article examines alternative approaches for representing a forest region to be scheduled for harvesting, where the primary concerns are maximizing return and imposing a maximum contiguous area of disturbance restriction. One approach assumes that any two adjacent management units exceed a regulated maximum area of disturbance. An alternative approach recognizes that management units may be substantially smaller than the maximum area restriction, so simultaneously disturbing two neighboring units does not necessarily represent a maximum area violation. The distinguishing feature of these two approaches is the way in which a forest is spatially represented. A single time period, 351 management unit harvest scheduling problem is utilized to investigate whether analysis results are subject to manipulation when forest representation, and associated modeling, is interpreted in different ways. Empirical results highlight significant economic and spatial variation in harvest schedules when maximum area restrictions are imposed using alternative approaches

Enhancing Equity in Public Transportation Using Geographic Information Systems and Spatial Optimization

Public transportation is a vital part of urban living. For instance, public transportation services help reduce road congestion, oil consumption and air pollution, and they serve people who need to travel throughout urban environments at the same time do not have access to private vehicles. The latter aspect is an important matter of social justice. Therefore, it is important to understand why the interest in equity in transport is growing, why public transportation should favor the transport disadvantaged, and why analyses of equity measurement and improvement are needed. Measuring the level of access to public transportation among the transport disadvantaged provides a theoretical basis for analyzing potential improvements in access by adjusting public transportation facility locations. This research will focus on modeling approaches used in establishing public transportation infrastructure and systems. Using GIS and spatial optimization models, the level of access to public transportation in terms of equity will be evaluated and improvement of the level of access will be attempted by offering new service stop locations. To this end, using the Maximal Covering Location Problem (MCLP), the optimal locations of potential facilities to cover equity favoring origin- and destination-based demand are identified. This research finally provides a set of optimal service stop locations maximizing coverage of origin- and destination-based demand simultaneously through implementation of a bi-objective model, applied to the City of Hilliard, Ohio