Global Positioning Systems leave valuable traces. Daniel works to improve our ability to infer some form of intent or additional information from GPS traces, such as intermediate locations visited as a person moves towards their ultimate destination. This has applications in numerous areas such as security, where the locations visited may yield information about the person, or in the case of a missing person, where the location information may help authorities reconstruct an accurate picture of where the person visited. In retail analysis, the locations inferred by GPS may guide decisions on opening an outlet at a specific destination. Daniel looks at anomalies in GPS traces, unusual data that stands out from the rest.  This will help in security and missing persons cases.