Measuring the structural similarity of network time prisms using temporal signatures with graph indices

New publication: Jaegal Y, Miller HJ. (2019) Measuring the structural similarity of network time prisms using temporal signatures with graph indices. Transactions in GIS. 00:1–24. https ://doi.org/10.1111/tgis.12582

Abstract.  The network‐time prism (NTP) is an extension of the space‐time prism that provides a realistic model of the potential pattern of moving objects in transportation networks. Measuring the similarity among NTPs can be useful for clustering, aggregating, and querying potential mobility patterns. Despite its practical importance, however, there has been little attention given to similarity measures for NTPs. In this research, we develop and evaluate a methodology for measuring the structural similarity between NTPs using the temporal signature approach. The approach extracts the one‐dimensional temporal signature of a selected property of NTPs and applies existing path similarity measures to the signatures. Graph‐theoretic indices play an essential role in summarizing the structural properties of NTPs at each moment. Two extensive simulation experiments demonstrate the feasibility of the approach and compare the performance of graph indices for measuring NTP similarity. An empirical application using bike‐share system data shows that the method is useful for detecting different usage patterns of two heterogenous user groups.

2017 Mapping Science Committee

I’m looking forward to chairing the Mapping Science Committee (MSC) of the US National Academies of Sciences, Engineering and Medicine! We have a great committee for the next three years:

  • Harvey J. Miller, Chair, The Ohio State University
  • Daniel G. Brown, University of Michigan
  • Stewart Fotheringham, Arizona State University
  • Henry Lin, Pennsylvania State University
  • Mark E. Reichardt, Open GIS Consortium, Inc.
  • Kathleen Stewart, University of Maryland
  • Kristin M. Tolle, Microsoft Research
  • Grady H. Tuell, 3D Ideas
  • Martha McCart Wells, Spatial Focus, Inc.

Here are the biographical sketches for this first-rate team.

The MSC organizes and oversees National Research Council studies that provide independent advice to society and to government at all levels on geospatial science, technology, and policy. It also addresses aspects of geographic information science that deal with the acquisition, integration, storage, distribution, and use of spatial data. Through its studies, the committee promotes the informed and responsible development and use of spatial data for the benefit of society.

Call for participation – NSF Workshops on Advancing Movement and Mobility Science

Recent years have witnessed the emergence of interdisciplinary scientific communities focusing on moving objects, motivated by technological advances in location-aware technologies for moving objects data (MOD) collection. In response to these challenges and opportunities, interdisciplinary communities are emerging that focus on the analysis of MOD to in order to provide new insights into complex spatio-temporal systems. However, a schism is also emerging between researchers focusing on human entities (e.g., people, vehicles, commodities) and animal entities (e.g., tigers, pandas, albatrosses, salmon).

A series of two workshops will bring together scholars working on animal movement ecology and human mobility science to generate a nascent interdisciplinary/cross-domain community focusing on the analysis of moving objects.  Specifically, the two workshops will address crucial issues that span both human mobility science and animal movement ecology:

  • Workshop 1: Measuring and interpreting interactions between and among moving objects (November 2016 in Austin, Texas)
  • Workshop 2: Analyzing moving entities within geographic context (May 2017 in Columbus, Ohio).

These workshops are supported by an award from the National Science Foundation (BCS 1560727)

Call for participation – Workshop 1: Measuring and analyzing interactions among mobile entities.   University of Texas-Austin, 10-11 November 2016

Interactions among mobile objects are a second-order but crucial property of movement.  In human mobility, interactions reflect actual or potential social interactions or shared activities, and are often the basis for the formation and maintenance of social networks and social capital.  In animal movement ecology, interactions can range from physical contact to sharing common resources, to simple awareness and are crucial for understanding spatial ecological processes and behaviors such as mating and territoriality, as well as epizootiology.

New advancements in collecting movement/location data enable more and better quality data to be collected, and have resulted in an increasing number of studies on animal or human interaction.  However, there have been few methodological advancements related to improving the ability to analyze and understand interactions. Most of the currently used interaction metrics were developed under a different paradigm of MOD collection (coarser spatial and temporal resolution) and the assumptions the metrics make (such as the way inherent expected values are calculated) are likely inappropriate in many applications to which they are applied.

We invite participation from researchers at any level who are involved in measuring and analyzing interactions among humans and/or animals.  Selected participants will receive travel reimbursement for legitimate expenses ranging from $500-$1000, with priority to students and unfunded scholars.

More information: sites.utexas.edu/interaction.

To be considered, submit the following:

  1. Brief cover letter indicating your intention to participate, and whether partial travel support is required
  2. A 750 word (maximum) abstract of your proposed presentation
  3. If travel support is required, a one to two sentence statement of need.
  4. A short CV (NSF style preferred; two pages maximum)

Please combine all of the above into one document (*.pdf preferred) named with your last name followed by first two initials (ex. MillerJA.pdf) and email as an attachment to Interac.ng0hvbomn4fo6pis@u.box.com.

Due date: 2 September 2016.

Workshop Co-organizers

  • Harvey J. Miller (The Ohio State University)
  • Jennifer A. Miller (University of Texas at Austin)
  • Gil Bohrer (The Ohio State University)

Steering Committee

  • Somayeh Dodge (University of Minnesota)
  • Joni Downs (University of South Florida)
  • Steven Farber (University of Toronto)
  • Wayne Getz (University of California – Berkeley)
  • Trisalyn Nelson (Arizona State University)
  • Kathleen Stewart (University of Maryland)
  • May Yuan (University of Texas – Dallas)