Preserving location privacy by distinguishing between public and private spaces

'Location Anonymization' seeks to preserve privacy in location data by blurring people's locations primarily when they are in places that are not public; the coordinates of someone in public are blurred less or not at all. The method also calls for tracking each person for only a limited time (e.g. 24 hours). The hope is that this method will allow individual traces to be distributed and used as data without aggregation. The method was evaluated with 21 GPS-derived tracks. Results are promising. The anonymization appears to be adequate, and the anonymized data are information-rich.