Dr. Rey’s work in spatial econometrics focuses on the performance of specification tests in regression models, efficient specification searches, alternative model formulations, and the transition to cyberinfrastructure. He has numerous publications that address topics of measurement, modeling and empirical analysis of regional income dynamics. He has introduced several innovative measures of regional convergence constructed from a spatial analytical perspective, such as spatial econometric approaches, new rank concordance indices, and Markov chain models. His 1999 article on this topic (Rey and Montouri 1999, “US regional income convergence, a spatial econometrics perspective,” Regional Studies), has been cited over 1000 times to date.
 
Apart from these theoretical and empirical advances, his contributions to open source software tools and advocacy for open spatial science have facilitated GIScience research world-wide. PySAL has been downloaded by thousands of researchers and programmers and is increasingly recognized as an important tool to facilitate spatial analysis both in the open source as well as in the commercial world. PySAL is now included in the open source scientific Python distributions by Enthought and Anaconda, and selected functionality is available as a plug-in for the popular Quantum GIS software (QGIS). Commercially, both ESRI’s ArcGIS and the cloud-based web mapping service CartoDB have adopted PySAL plug-ins, thereby making its analytical functionality available to thousands of GIS users.