There have been several obstacles to an embrace of critical theoretical work in GIScience; chief among them is the barrier between conceptualization and formalization. Early critics of the technology ...were not cognizant that technological change must be implemented within the language of code. While critics expressed their concerns in a theoretical and esoteric language, increasingly GIScientists are at pains to address the same issues so that solutions can be incorporated into software technologies. Indeed an implicit recognition of the important divide between informal and formal environments has aided GIScience researchers in developing strategies to represent multiple epistemologies in GIS. The article begins with a review of early critical GIScience, examines the degree of its acceptance in the light of a content analysis of GIS journals, and then illustrates that the issue of multiple representation of the same reality is being addressed under the rubric of ontologies. New research in this area has had significant impact on GIScience because it has been articulated and addressed at both the conceptual and formal stages-a criterion for real changes to both GISystems and GIScience. The article concludes with an examination of why critical GIS remains relevant to the discipline, in spite of efforts to address issues of representation within GIScience.
Injury is a leading cause of the global disease burden, accounting for 10 percent of all deaths worldwide. Despite 90 percent of these deaths occurring in low and middle-income countries (LMICs), the ...majority of trauma research and infrastructure development has taken place in high-income settings. Furthermore, although accessible services are of central importance to a mature trauma system, there remains a paucity of literature describing the spatial accessibility of emergency services in LMICs. Using data from the Service Provision Assessment component of the Demographic and Health Surveys of Namibia and Haiti we defined the capabilities of healthcare facilities in each country in terms of their preparedness to provide emergency services. A Geographic Information System-based network analysis method was used to define 5- 10- and 50-kilometer catchment areas for all facilities capable of providing 24-hour care, higher-level resuscitative services or tertiary care. The proportion of a country's population with access to each level of service was obtained by amalgamating the catchment areas with a population layer. A significant proportion of the population of both countries had poor spatial access to lower level services with 25% of the population of Haiti and 51% of the population of Namibia living further than 50 kilometers from a facility capable of providing 24-hour care. Spatial access to tertiary care was considerably lower with 51% of Haitians and 72% of Namibians having no access to these higher-level services within 50 kilometers. These results demonstrate a significant disparity in potential spatial access to emergency services in two LMICs compared to analogous estimates from high-income settings, and suggest that strengthening the capabilities of existing facilities may improve the equity of emergency services in these countries. Routine collection of georeferenced patient and facility data in LMICs will be important to understanding how spatial access to services influences outcomes.
Geographic masks are techniques used to protect individual privacy in published maps but are highly under-utilized in research. This leads to continual violations of individual privacy, as sensitive ...health records are put at risk in unmasked maps. New approaches to geographic masking are required that foster accessibility and ease of use, such that they become more widely adopted. This article describes a new geographic masking method, called street masking, that reduces the burden on users of finding supplemental population data by instead automatically retrieving OpenStreetMap data and using the road network as a basis for masking. We compare it to donut geomasking, both with and without population density taken into account, to evaluate its efficacy against geographic masks that require slightly less and slightly more supplemental data. Our analysis is performed on synthetic data in three different Canadian cities.
Street masking performs similarly to population-based donut geomasking with regard to privacy protection, achieving comparable k-anonymity values at similar median displacement distances. As expected, distance-based donut geomasking performs worst at privacy protection. Street masking also performs very well regarding information loss, achieving far better cluster preservation and landcover agreement than population-based donut geomasking. Distance-based donut geomasking performs similarly to street masking, though at the cost of reduced privacy protection.
Street masking competes with, if not out-performs population-based donut geomasking and does so without requiring any supplemental data from users. Moreover, unlike most other geographic masks, it significantly minimizes the risk of false attribution and inherently takes many geographic barriers into account. It is easily accessible for Python users and provides the foundation for interfaces to be built for non-coding users, such that privacy can be better protected in sensitive geospatial research.
Aging adult skeletal material is a crucial component of building the biological profile of unknown skeletal remains, but many macro‐ and microscopic methods have challenges regarding accuracy, ...precision, and replicability. This study developed a volumetric method to visualize and quantify histological remodeling events in three dimensions, using a two‐dimensional serialized approach that applied circular polarizing microscopy and geographic information systems protocols. This approach was designed as a tool to extend current histological aging methodologies. Three serial transverse sections were obtained from a human femoral midshaft. A total sample size of 6847 complete osteons from the three sections was identified; 1229 osteons connected between all sections. The volume of all connected osteons was interpolated using ArcGIS area calculations and truncated cone geometric functions. Each section was divided into octants, and two random samples of 100 and of 30 connected osteons from each octant were generated. Osteon volume was compared between the octants for each random sample using ANOVA. Results indicated that the medial aspect had relative uniformity in osteon volume, whereas the lateral aspect showed high variability. The anterolateral–lateral octant had significantly smaller osteon volume, whereas the posterior–posterolateral octant had significantly larger osteon volume. Results also indicated that a minimum of 100 osteons is statistically more robust and more representative of normal osteon distribution and volume; the use of 30 osteons is insufficient. This research has demonstrated that osteon volume can be interpolated using spatial geometry and GIS applications and may be a tool to incorporate into adult age‐at‐death estimation techniques.
Online charitable crowdfunding has become an increasingly prevalent way for Canadians to deal with costs that they would otherwise not be able to shoulder on their own. With the onset of COVID-19 and ...related lockdown measures, there is evidence of a surge in crowdfunding use relating to the pandemic. This study gathered, classified, and analysed Canadian crowdfunding campaigns created in response to COVID-19 from GoFundMe.com, a popular crowdfunding platform. Spatio-temporal analysis of classified campaigns allowed for observation of emergent trends in the distribution of pandemic-related need incidence and financial support throughout the pandemic. Campaigns raising money on behalf of established charities were the most common in the sample, and accounted for the greatest portion of funding raised, while campaigns for businesses made up a small proportion. Dense metropolitan areas accounted for the vast majority of campaign locations, and total sample funding was disproportionately raised by campaigners in Ontario and British Columbia.
GIS eased into geography without much discord until the 1990s, when a flurry of commentaries about the relative merits of GIS made their way into a number of geographic journals. The ensuing decade ...was marked by varying degrees of friction between GIS practitioners and their critics in human geography. Despite the methodological chasm between the two groups, little discussion of the implications of these differences has ensued. This article fills that gap with a historiographic examination of critiques of GIS. Critiques of GIS are organized into three waves or periods, each characterized by distinct arguments. The first wave, from 1990 to 1994, was marked by the intensity of debate as well as an emphasis on positivism. By 1995, the conversation waned as the number of critics grew, while GIS practitioners increasingly declined comment. This second wave marked the initiation of a greater degree of co-operation between GIS scholars and their critics, however. With the inception of the National Center for Geographic Information Analysis (NCGIA) Initiative 19, intended to study the social effects of GIS, many critics began to work closely with their peers in GIS. In the third wave, critiques of GIS expressed a greater commitment to the technology. Throughout the decade, debates about the technology shifted from simple attacks on positivism to incorporating more subtle analyses of the effects of the technology. These critiques have had considerable effect on the academic GIS community but are presently constrained by limited communication with GIS practitioners because of the absence of a common vocabulary. I argue that, if critiques of GIS are to be effective, they must find a way to address GIS researchers, using the language and conceptual framework of the discipline.
There is increasing interest in examining the influence of the built environment on physical activity. High-resolution data in a geographic information system is increasingly being used to measure ...salient aspects of the built environment and studies often use circular or road network buffers to measure land use around an individual's home address. However, little research has examined the extent to which the selection of circular or road network buffers influences the results of analysis. The objective of this study is to examine the influence of land use type (residential, commercial, recreational and park land and institutional land) on 'walking for leisure' and 'walking for errands' using 1 km circular and line-based road network buffers. Data on individual walking patterns is obtained from a survey of 1311 respondents in greater Vancouver and respondent's postal code centroids were used to construct the individual buffers. Logistic regression was used for statistical analysis.
Using line-based road network buffers, increasing proportion of institutional land significantly reduced the odds of 'walking for leisure 15 minutes or less per day' no significant results were found for circular buffers. A greater proportion of residential land significantly increased the odds of 'walking for errands less than 1 hour per week' for line-based road network buffer while no significant results for circular buffers. An increased proportion of commercial land significantly decreased the odds of 'walking for errands less than 1 hour per week' for both circular and line-based road network buffers.
The selection of network or circular buffers has a considerable influence on the results of analysis. Land use characteristics generally show greater associations with walking using line-based road network buffers than circular buffers. These results show that researchers need to carefully consider the most appropriate buffer with which to calculate land use characteristics.
High-risk cancer resection surgeries are increasingly being performed at fewer, more specialised, and higher-volume institutions across Canada. The resulting increase in travel time for patients to ...obtain treatment may be exacerbated by socioeconomic barriers to access. Focussing on five high-risk surgery types (oesophageal, ovarian/fallopian, liver, lung, and pancreatic cancers), this study examines socioeconomic trends in age-adjusted resection rates and travel time to surgery location for urban, suburban, and rural populations across Canada, excluding Québec, from 2004 to 2012. Significant differences in age-adjusted resection rates were observed between urban (14.9 per 100 000 person-years 95% CI: 12.2, 17.6), suburban (40.7 40.1, 41.2), and rural (32.7 29.6, 35.9) populations, with higher rates in suburban and rural areas throughout the study period for all cancer types. Resection rates did not differ between the highest (Q1) and lowest (Q5) socioeconomic strata (Q1: 13.3 12.2, 14.4; Q5: 12.0 10.7, 13.4), with significantly higher rates among middle-SES patients (Q2: 27.3 25.6, 29.0; Q3: 39.6 37.4, 41.8; Q4: 37.5 35.3, 39.7). Travel times to treatment were consistently higher among the most socioeconomically deprived patients, most notably in suburban and rural areas. The results suggest that the conventional inclusion of suburbs with urban areas in health research may obfuscate important trends for public health policy and programmes.
Human behaviour is an obvious, yet under-studied factor in pedestrian injury. Behavioural interventions that address rule violations by pedestrians and motorists could potentially reduce the ...frequency of pedestrian injury. In this study, a method was developed to examine road-rule non-compliance by pedestrians and motorists. The purpose of the study was to examine the potential association between violations made by pedestrians and motorists at signalized intersections, and collisions between pedestrians and motor-vehicles. The underlying hypothesis is that high-incident pedestrian intersections are likely to vary with respect to their aetiology, and thus are likely to require individualized interventions--based on the type and rate of pedestrian and motorist violation.
High-incident pedestrian injury intersections in Vancouver, Canada were identified using geographic information systems. Road-rule violations by pedestrians and motorists were documented at each incident hotspot by a team of observers at several different time periods during the day.
Approximately 9,000 pedestrians and 18,000 vehicles were observed in total. In total for all observed intersections, over 2000 (21%) pedestrians committed one of the observed pedestrian road-crossing violations, while approximately 1000 (5.9%) drivers committed one of the observed motorist violations. Great variability in road-rule violations was observed between intersections, and also within intersections at different observation periods.
Both motorists and pedestrians were frequently observed committing road-rule violations at signalized intersections, suggesting a potential human behavioural contribution to pedestrian injury at the study sites. These results suggest that each intersection may have unique mechanisms that contribute to pedestrian injury, and may require targeted behavioural interventions. The method described in this study provides the basis for understanding the relationship between violations and pedestrian injury risk at urban intersections. Findings could be applied to targeted prevention campaigns designed to reduce the number of pedestrian injuries at signalized intersections.
Childrens' outdoor active play is an important part of their development. Play behaviour can be predicted by a variety of physical and social environmental features. Some of these features are ...difficult to measure with traditional data sources. This study investigated the viability of a machine learning method using Google Street View images for measurement of these environmental features. Models to measure natural features, pedestrian traffic, vehicle traffic, bicycle traffic, traffic signals, and sidewalks were developed in one city and tested in another. The models performed well for features that are time invariant, but poorly for features that change over time, especially when tested outside of the context where they were initially trained. This method provides a potential automated data source for the development of prediction models for a variety of physical and social environment features using publicly accessible street view images.
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