Campus Units

Center for Statistics and Applications in Forensic Evidence (CSAFE)"

Document Type


Publication Version

Published Version

Publication Date


Journal or Book Title

Forensic Science International: Digital Investigation



First Page



A common question in forensic analysis is whether two observed data sets originated from the same source or from different sources. Statistical approaches to addressing this question have been widely adopted within the forensics community, particularly for DNA evidence. Here we investigate the application of statistical approaches to same-source forensic questions for spatial event data, such as determining the likelihood that two sets of observed GPS locations were generated by the same individual. We develop two approaches to quantify the strength of evidence in this setting. The first is a likelihood ratio approach based on modeling the spatial event data directly. The second approach is to instead measure the similarity of the two observed data sets via a score function and then assess the strength of the observed score resulting in the score-based likelihood ratio. A comparative evaluation using geolocated Twitter event data from two large metropolitan areas shows the potential efficacy of such techniques.


This article is published as Galbraith, Christopher, Padhraic Smyth, and Hal S. Stern. "Statistical methods for the forensic analysis of geolocated event data." Forensic Science International: Digital Investigation 33 (2020): 301009. Posted with permission of CSAFE.

Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Copyright Owner

The Authors



File Format