Visualization of Attributed Hierarchical Structures in a Spatiotemporal Context

International Journal of Geographical Information Science, Volume 24 Issue 10 2010, Pages 1497 – 1513: Geospatial Visual Analytics: Focus on Time Special Issue of the ICA Commission on GeoVisualization

S. Hadlak; C. Tominski; H. -J. Schulz; H. Schumann

“When visualizing data, spatial and temporal references of these data often have to be considered in addition to the actual data attributes. Nowadays, structural information is becoming more and more important. Hierarchies, for instance, are frequently applied to make large and complex data manageable. Hence, a visual depiction of hierarchical structures in space and time is required.

“Although there are several techniques addressing specific aspects of spatio-temporal visualization, approaches that cope with space, time, data, and structure are rare. With this article we take a step to fill this gap. By combining various well-established concepts, we achieve a reasonably complete visualization of all of the aforementioned aspects, where our focus is on the hierarchical structures. We embed hierarchies directly into the regions of a map display using variants of the point-based layout. Layering and animation are applied to visualize temporal aspects. Based on the analysis goals, users can switch between representations that emphasize data attributes or hierarchical structures. Interaction techniques support users in navigating the data and their visualization. We demonstrate the usefulness of our approach by adapting it to implement a visualization for spatiotemporal human health data.”

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Young and Vulnerable: Spatial-temporal Trends and Risk Factors for Infant Mortality in Rural South Africa (Agincourt), 1992-2007

BMC Public Health 2010, 10:645, Published 26 October 2010

Benn KD Sartorius, Kathleen Kahnl, Penelope Vounatsou, Mark A Collinson, and Stephen M Tollman

“Background: Infant mortality is an important indicator of population health in a country. It is associated with several health determinants, such as maternal health, access to high-quality health care, socioeconomic conditions, and public health policy and practices.

“Methods: A spatial-temporal analysis was performed to assess changes in infant mortality patterns between 1992-2007 and to identify factors associated with infant mortality risk in the Agincourt sub-district, rural northeast South Africa. Period, sex, refugee status, maternal and fertility-related factors, household mortality experience, distance to nearest primary health care facility, and socio-economic status were examined as possible risk factors. All-cause and cause-specific mortality maps were developed to identify high risk areas within the study site. The analysis was carried out by fitting Bayesian hierarchical geostatistical negative binomial autoregressive models using Markov chain Monte Carlo simulation. Simulation-based Bayesian kriging was used to produce maps of all-cause and cause-specific mortality risk.

“Results: Infant mortality increased significantly over the study period, largely due to the impact of the HIV epidemic. There was a high burden of neonatal mortality (especially perinatal) with several hot spots observed in close proximity to health facilities. Significant risk factors for all-cause infant mortality were mother’s death in first year (most commonly due to HIV), death of previous sibling and increasing number of household deaths. Being born to a Mozambican mother posed a significant risk for infectious and parasitic deaths, particularly acute diarrhoea and malnutrition.

“Conclusions: This study demonstrates the use of Bayesian geostatistical models in assessing risk factors and producing smooth maps of infant mortality risk in a health and socio-demographic surveillance system. Results showed marked geographical differences in mortality risk across a relatively small area. Prevention of vertical transmission of HIV and survival of mothers during the infants’ first year in high prevalence villages needs to be urgently addressed, including expanded antenatal testing, prevention of mother-to-child transmission, and improved access to antiretroviral therapy. There is also need to assess and improve the capacity of district hospitals for emergency obstetric and newborn care. Persisting risk factors, including inadequate provision of clean water and sanitation, are yet to be fully addressed.”

From Doves to Hawks: A Spatial Analysis of Voting in the Monetary Policy Committee of the Bank of England

European Journal of Political Research, 49 (6). pp. 731-758 (2010)

Hix, Simon; Holyland, Bjorn; and Vivyan, Nick

“This article examines the making of monetary policy in the United Kingdom between 1997 and 2008 by analysing voting behaviour in the Bank of England’s Monetary Policy Committee (MPC). It provides a new set of measures for the monetary policy preferences of individual MPC members by estimating a Bayesian item response model. The article demonstrates the usefulness of these measures by comparing the ideal points of outgoing MPC members with their successors and by looking at changes over time in the median ideal point on the MPC. The analysis indicates that the British Government has been able to move the position of the median voter on the MPC through its appointments to the Committee. This highlights the importance of central bank appointments for monetary policy.”

Application of Spatial Analysis Methods for Understanding Geographic Variation of Prices, Demand and Market Success

A dissertation submitted to ETH ZURICH for the degree of Doctor of Sciences, 2010

Michael Löchl

“Spatial analysis is a general term to describe mathematical methods that use locational information in order to better understand processes generating observed attribute values (Fotheringham and Rogerson, 2009, 1). Such techniques are applied in many fields, including biology, epidemiology, ethnology, geography, sociology and statistics. Nevertheless, the nature of the spatial variation of interest is sometimes not well understood and the patterns of spatial dependence and heterogeneity are disregarded. Therefore, this dissertation brings together different applications of spatial analysis methods for understanding geographic variation of certain entities while considering those spatial effects. Additionally, certain spatial analysis, modelling and simulation techniques are examined for solving location problems and informing spatial allocation and deployment of resources. Namely, regression techniques, integrated land use and transport simulation and agent-based modelling approaches are applied in four examples, whereas all those techniques are grounded in spatial analysis.”

Space–time Density of Trajectories: Exploring Spatio-temporal Patterns in Movement Data

International Journal of Geographical Information Science, Volume 24 Issue 10 2010, Pages 1527 – 1542: Geospatial Visual Analytics: Focus on Time Special Issue of the ICA Commission on GeoVisualization

Urška Demšar; Kirsi Virrantaus

“Modern positioning and identification technologies enable tracking of almost any type of moving object. A remarkable amount of new trajectory data is thus available for the analysis of various phenomena. In cartography, a typical way to visualise and explore such data is to use a space-time cube, where trajectories are shown as 3D polylines through space and time. With increasingly large movement datasets becoming available, this type of display quickly becomes cluttered and unclear. In this article, we introduce the concept of 3D space-time density of trajectories to solve the problem of cluttering in the space-time cube. The space-time density is a generalisation of standard 2D kernel density around 2D point data into 3D density around 3D polyline data (i.e. trajectories). We present the algorithm for space-time density, test it on simulated data, show some basic visualisations of the resulting density volume and observe particular types of spatio-temporal patterns in the density that are specific to trajectory data. We also present an application to real-time movement data, that is, vessel movement trajectories acquired using the Automatic Identification System (AIS) equipment on ships in the Gulf of Finland. Finally, we consider the wider ramifications to spatial analysis of using this novel type of spatio-temporal visualisation.”

Third Annual T3G Institute for GIS Educators: Teachers Teaching Teachers GIS

Program Helps Instructors Refine Teaching Techniques and Expand Capabilities

Esri has opened the application period for its third annual Teachers Teaching Teachers GIS (T3G) Institute, to be held at Esri headquarters in Redlands, California, from June 12 to 17, 2011.

Digital maps and globes have become commonplace. The challenge for educators is to guide their students beyond a simple view of the world and into analysis, which is crucial for jobs related to science, technology, engineering, and mathematics (STEM). T3G provides intense training to teachers who want to help other educators use geographic information system (GIS) technology in their classes.

“We’re looking for 30 strong candidates for the program this year,” says Charlie Fitzpatrick, Esri K–12 Schools solution manager. “Our T3G Institute helps experienced GIS educators turbocharge their skills so that they can help teachers new to GIS. Those teachers can then present their students with better integrated knowledge, powerful career skills, and opportunities for community engagement.”

In the weeklong institute, attendees experience the latest developments in GIS education and software. They expand their GIS skills in areas including spatial analysis, data management, and GIS project workflow. T3G participants exchange ideas with peers, learn teaching strategies from top trainers, and develop lasting professional relationships.

“What I liked about T3G was the variety of different instructional strategies,” reflects Robert Jones, a retired technology teacher from the Hannibal (New York) School District, who attended T3G 2010. “I learned that there are a lot of simple things you can do to hook people into GIS. I think that the technology has a real role in K–12 education—providing students a glimpse into new careers, examining real-world issues, and making better informed decisions about our world. Being at T3G has enhanced my ability to share that with others.”

T3G 2011 is sponsored in part by the National Geospatial Technology Center of Excellence (GeoTech Center), an organization that supports GIS learning initiatives among the higher education community. It is funded by a grant from the National Science Foundation.

Additional information, including the application, can be found on the Esri T3G Institute Web site at edcommunity.esri.com/t3g. Applications are due by November 30, 2010, and institute invitations will be sent by December 17.

[Source: Esri press release]

Call for Presentations: Special GIScience Research Track ESRI International Users Conference

ESRI invites you to present a peer-reviewed paper presentation in a special joint GIScience Research Track for the 2011 ESRI International Users Conference and Educational Users Conference. Papers in this special tract must focus on cutting-edge research in GIScience. Full papers will be included in a special issue of Transactions in GIS to be distributed at the 2011 International Users and Education Users Conferences. Abstracts (500 words) must be submitted to Dr. John Wilson, University of Southern California, by 1st December, 2010.

The Transactions in GIS editorial team will review abstracts based on their GIScience content and select nine abstracts to become full papers. Notice of acceptance will occur by 8th December, 2010. Full papers (maximum 6,000 words plus figures, tables, and references in appropriate format for publication) must be submitted to Dr. Wilson for independent review by 1st February, 2011. Reviewed papers will be returned to authors by 1st March, 2011 and final manuscripts must be returned by 15th March, 2011, to be included in the special issue of Transactions in GIS.

For questions or guidelines on this special GIScience Research Track, please see: http://www.esri.com/GIScience or contact Michael Gould at mgould@esri.com.

Abstracts should be submitted via e-mail with a subject line “ESRI GIScience Abstract, Authors Last Name” no later than 1st December, 2010 to:

Dr. John Wilson, jpwilson@college.usc.edu.

[Source: GIS Education Community blog]

Analysing Spatio-temporal Autocorrelation with LISTA-Viz

International Journal of Geographical Information Science, Volume 24 Issue 10 2010, Pages 1515 – 1526: Geospatial Visual Analytics: Focus on Time Special Issue of the ICA Commission on GeoVisualization

F. Hardisty; A. Klippel

“Many interesting analysis problems (e.g. disease surveillance) would become more tractable if their spatio-temporal structure was better understood. Specifically, it would be helpful to be able to identify autocorrelation in space and time simultaneously. Some of the most commonly used measures of spatial association are LISA statistics, such as the Local Moran’s I or the Getis-Ord Gi*; however, these have not been applied to the spatio-temporal case (including many time steps) because of computational limitations. We have implemented a spatio-temporal version of the Local Moran’s I and claimed two advances: first, we exploit the fact that there are a limited number of topological relationships present in the data to make Monte Carlo’s estimation of probability densities computationally practical, and thereby bypass the ‘curse of dimensionality’. We term this approach ‘spatial memoization’. Second, we developed a tool (LISTA-Viz) for interacting with the spatio-temporal structure uncovered by the statistics that contains a novel coordination strategy. The potential usefulness of the method and the associated tool are illustrated by an analysis of the 2009 H1N1 pandemic, with the finding that there was a critical spatio-temporal ‘inflection point’ at which the pandemic changed its character in the United States.”

Reflections on the Science and Art of Using a GIS to locate a New National Children’s Hospital in Ireland

Irish Geography, Volume 42, Issue 2 July 2009 , pages 245 – 252

Frank Houghton

“The paper by Murphy and Killen (2007) represents the latest in a growing body of Irish work exploring the use of GIS as spatial decision support systems to investigate future developments in hospital provision in Ireland (see also Teljeur et al. 2004, Kalogirou and Foley 2006). The uneven and relatively delayed development of Health GIS in Ireland to date has previously been noted (Houghton 2001a, 2001b, 2004a). Similar to the work of Teljeur and Kelly (2006), this latest piece by Murphy and Killen explores options for the location of the proposed new national paediatric hospital using a GIS. A focus on the issue of access to healthcare is crucial, because as Wennberg (1998, p. 2) notes ‘in health care, geography is destiny’.