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CV-33 - Narrative and Storytelling

Maps are powerful storytellers. Maps have a long history combining spatial relations with cartographic language to locate, analyze, ground, and express stories told across time and space. Today, “story maps” are increasingly visible in cartography, GIScience, digital humanities, data visualization, and journalism due to the volume of available data and increasingly accessible mapping tools. Perhaps, most importantly, maps present world views and much larger (often hidden) stories or “meta-narratives.” These underlying stories often emerge from dominant perspectives that are deeply informed by power structures like racism, patriarchy, ableism, etc. and further generate uneven geographies. Attention to power in narrative and storytelling reveals and gives voice to alternative storylines and perspectives that can be woven together across time and space. In this entry, I introduce multiple conceptualizations of maps and stories from cartography and data journalism to feminist mapping, Black geographies, and decolonial mapping to illustrate the power of narrative and storytelling in mapping. I argue that understanding the power of narrative and storytelling in mapping is an essential skillset for students and professionals alike.

DA-18 - GIS&T and Disaster Management

Geographic Information Science and Technology (GIS&T) has a long-running tradition of using spatially-oriented methodologies and representational techniques such as cartography and mapping to address hazards and disasters. This tradition remains important as ever as global society faces newer and more complex challenges resulting from climate change and new challenges such as the COVID-19 pandemic. GIS&T has become an invisible technology within the disaster management cycle of planning and preparedness, response, recovery, and mitigation. Spatial technologies such as geographic information systems (GIS), remote sensing techniques, spatial data science, artificial intelligence, and machine learning are now widespread and pervasive. Despite these advancements, there is more that can be done to incorporate GIS&T perspectives into disaster management. In this article, we outline important conceptual ideas to consider on the use of GIS&T for disaster management, disaster management organizations that use GIS&T, and practical information to orient newcomers to this exciting and important interdisciplinary combination.

AM-40 - Areal Interpolation

Areal interpolation is the process of transforming spatial data from source zones with known values or attributes to target zones with unknown attributes. It generates estimates of source zone attributes over target zone areas. It aligns areal spatial data attributes over a single spatial framework (target zones) to overcome differences in areal reporting units due to historical boundary changes of reporting areas, integrating data from domains with different reporting conventions or in situations when spatially detailed information is not available. Fundamentally, it requires assumptions about how the target zone attribute relates to the source zones. Areal interpolation approaches can be grouped into two broad categories: methods that link target and source zones by their spatial properties (area to point, pycnophylactic and areal weighed interpolation) and methods that use ancillary or auxiliary information to control, inform, guide, and constrain the interpolation process (dasymetric, statistical, streetweighted and point-based interpolation). Additionally, there are new opportunities to use novel data sources to inform areal interpolation arising from the many new forms of spatial data supported by ubiquitous web- and GPS-enabled technologies including social media, PoI check-ins, spatial data portals (e.g for crime, house sales, microblogging sites) and collaborative mapping activities (e.g. OpenStreetMap).

DA-13 - GIS&T in Criminal Justice and Law Enforcement

Linking crime and place has been the objective of crime mapping since the early nineteenth century. Contemporary scholars have since investigated spatio-temporal crime patterns to explain why crime concentrates in certain places during certain times. Collectively, this body of research has identified various environmental and situational factors that contribute to the formation of crime hot spots and spawned widespread crime prevention and reduction strategies commonly referred to as place-based policing.  Environmental criminology guides the bulk of this crime-and-place research and provides a means for interpreting place and crime. The chapter details theories behind place-based policing, examples of place-based policing strategies that leverage geographic information science and its associated technologies (GIS&T), and relevant data visualization tools used by law enforcement to implement place-based strategies to address crime.

DA-47 - GIS&T in International Affairs

GIS applications within the International Affairs domain are vast, and they include: the analysis and representation of flows and stops of people, resources, and capital across borders, humanitarian assistance, war, conflict, and surveillance, and analysis of border-crossing spatial phenomena such as natural disasters and climate change.

Due to the wide range of potential thematic data, GIS for International Affairs should be a balance of hands-on practical application skills and critical thinking about spatial concepts of scale, boundaries, borders, and flows. GIS scholars and practitioners in this domain should learn to think critically about how and where spatial data is created, the people and cultures impacted by spatial data-driven decisions, and the equity of who is involved in such decisions. Students should learn how spatial data is created, how major datasets in the field are built, and how to design datasets during fieldwork for robust spatial analysis. Through all of this, critical thinking around which people and places are counted and represented should be maintained.

GIS in International Affairs must always contend with the colonial history of cartography, seeking now to understand how modern-day spatial technologies are always constituted by and embedded in constructions of power.

AM-04 - Overlay

Overlay operation is a critical and powerful tool in GIS that superimposes spatial and attribute information from various thematic map layers to produce new information. Overlay operations facilitate spatial analysis and modeling processes when being used with other spatial operations (e.g. buffer, dissolve, merge) to solve real-world problems. For both vector and raster data models, the input layers need to be spatially aligned precisely with each other to ensure a correct overlay operation. In general, vector overlay is geometrically and computationally complex. Some most used vector overlay operations include intersection, union, erase, and clip. Raster overlay combines multiple raster layers cell by cell through Boolean, arithmetic, or comparison operators. This article provides an overview of the fundamentals of overlay operations, how they are implemented in vector and raster data, and how suitability analysis is conducted.

DM-52 - Horizontal (Geometric) Datums

A horizontal (geometric) datum provides accurate coordinates (e.g., latitude and longitude) for points on Earth’s surface. Historically, surveyors developed a datum using optically sighted instruments to manually place intervisible survey marks in the ground. This survey work incorporated geometric principles of baselines, distances, and azimuths through the process of triangulation to attach a coordinate value to each survey mark. Triangulation produced a geodetic network of interconnected survey marks that realized the datum (i.e., connecting the geometry of the network to Earth’s physical surface). For local surveys, these datums provided reasonable positional accuracies on the order of meters. Importantly, once placed in the ground, these survey marks were passive; a new survey was needed to determine any positional changes (e.g., due to plate motion) and to update the attached coordinate values. Starting in the 1950s, due to the implementation of active control, space-based satellite geodesy changed how geodetic networks were realized. Here, "active" implies that a survey mark’s coordinates are updated in near real-time through, for example, artificial satellites such as GNSS. Increasingly, GNSS and satellite geodesy is paving the way for a modernized geometric datum that is global in scope and capable of providing positional accuracies at the millimeter level.

AM-46 - Location-allocation modeling

Location-allocation models involve two principal elements: 1) multiple facility location; and 2) the allocation of the services or products provided by those facilities to places of demand. Such models are used in the design of logistic systems like supply chains, especially warehouse and factory location, as well as in the location of public services. Public service location models involve objectives that often maximize access and levels of service, while private sector applications usually attempt to minimize cost. Such models are often hard to solve and involve the use of integer-linear programming software or sophisticated heuristics. Some models can be solved with functionality provided in GIS packages and other models are applied, loosely coupled, with GIS. We provide a short description of formulating two different models as well as discuss how they are solved.

FC-04 - Perception and Cognitive Processing of Geographic Phenomena: a Choropleth Map Case Study

The near ubiquity of maps has created a population the is well adept at reading and understanding maps.  But, while maps are familiar, understanding how the human brain processes that information is less known.  Discussing the processing of geographic phenomena could take different avenues: specific geospatial thinking skills, general perception and cognition processes, or even different parts of the human brain that are invoked when thinking geographically.  This entry focuses on tracing the processing of geographic phenomena using a choropleth map case study, beginning from perception — the moment the phenomena enter the human brain via our senses, to cognition — how meaning and understanding are generated. 

DM-01 - Spatial Database Management Systems

A spatial database management system (SDBMS) is an extension, some might say specialization, of a conventional database management system (DBMS).  Every DBMS (hence SDBMS) uses a data model specification as a formalism for software design, and establishing rigor in data management.  Three components compose a data model, 1) constructs developed using data types which form data structures that describe data, 2) operations that process data structures that manipulate data, and 3) rules that establish the veracity of the structures and/or operations for validating data.  Basic data types such as integers and/or real numbers are extended into spatial data types such as points, polylines and polygons in spatial data structures.  Operations constitute capabilities that manipulate the data structures, and as such when sequenced into operational workflows in specific ways generate information from data; one might say that new relationships constitute the information from data.  Different data model designs result in different combinations of structures, operations, and rules, which combine into various SDBMS products.  The products differ based upon the underlying data model, and these data models enable and constrain the ability to store and manipulate data. Different SDBMS implementations support configurations for different user environments, including single-user and multi-user environments.  

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