Using Open Source to support Transportation Research: Nonmotorized Travel Analysis Toolkit (NMTK)
A common challenge with niche research, notably in the realm of bicycle and pedestrian travel, is that research results can be very difficult to evaluate and reproduce outside of the context in which the research was originally conducted. In addition, academic research always favors “novel” and “unique” approaches, rather than carefully testing out work in new contexts and incrementally building toward a complete well-developed analytic solution. In many fields there is also a crisis of “reproducible research”, where poorly vetted results are presented as universally true, only to later be revealed as artifacts of limited data initially evaluated.
To help resolve these problems in support of better bicycle and pedestrian research, the US Federal Highway Administration sponsored a research project to develop a distributed framework that enables researchers to publish their models and results using a “software as a service” model through which others can evaluate their own local data. The resulting Non-Motorized Travel Analysis Toolkit (NMTK) provides a simple user interface to a distributed web application that enables users to explore available tools using sample data sets, upload their own data for analysis, use a simple data explorer to visualize and inspect results, and to download those results for further analysis. The framework in turn allows tool developers to use a simple API and supporting resources to write tools with documentation, sample data, and Python or R code to quickly and painlessly take advantage of the NMTK’s data management and spatially-enabled visualization interface in order to deliver their work to other researchers or the public for evaluation and use. The resulting system allows rapid deployment of new tools and research results, in a form that is directly useful for using the tools or evaluating their performance with new data sets.
The flagship installation of the NMTK is currently deployed as a public beta at the Pedestrian & Bicycle Information Center (PBIC) housed in the Highway Safety Research Center at UNC Chapel Hill. The NMTK consists of a server/UI component and a distributed system of "tools", which can be distributed over geographically diverse servers, and which are all accessed using a unified web interface. Built on an open-source framework (GeoDjango, GDAL/OGR, PostGIS, and MapServer) the NMTK provides an easy-to-use visualization interface that supports a wide range of raster and vector formats, and related processing tools.
The NMTK is an excellent example of leveraging open source GIS to improve the quality and availability of research products, and has the potential to become a conduit for widespread use of tools that would otherwise be consigned to obscure volumes of academic research publications. This presentation will introduce the rationale for the NMTK, describe its architecture and implementation platform, and offer a brief demonstration of its capabilities. In addition to being available “live” at PBIC, the NMTK code is fully open source under a BSD-style license, and can be downloaded from a public Github repository.