Trajectory anonymity in publishing personal mobility data
Bibliographic record
Abstract
Recent years have witnessed pervasive use of location-aware devices such as GSM mobile phones, GPS-enabled PDAs, location sensors, and active RFID tags. The use of these devices generates a huge collection of spatio-temporal data, variously called moving object data, trajectory data, or moblity data. These data can be used for various data analysis purposes such as city traffic control, mobility management, urban planning, and location-based service advertisements. Clearly, the spatio-temporal data so collected may help an attacker to discover personal and sensitive information like user habits, social customs, religious and sexual preferences of individuals. Consequently, it raises serious concerns about privacy. Simply replacing users' real identifiers (name, SSN, etc.) with pseudonyms is insufficient to guarantee anonymity. The problem is that due to the existence of quasi-identifiers, i.e., spatio-temporal data points that can be linked to external information to re-identify individuals, the attacker may be able to trace the anonymous spatio-temporal data back to individuals. In this survey, we discuss recent advancement on anonymity preserving data publishing of moving object databases in an off-line fashion. We first introduce several anonymity models, then we describe in detail some of the proposed techniques to enforce trajectory anonymity, discussing their merits and limitations. We conclude by identifying challenging open problems that need attention.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.018 | 0.069 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.002 | 0.001 |
| Bibliometrics | 0.003 | 0.009 |
| Science and technology studies | 0.004 | 0.004 |
| Scholarly communication | 0.009 | 0.021 |
| Open science | 0.004 | 0.009 |
| Research integrity | 0.002 | 0.003 |
| Insufficient payload (model declined to judge) | 0.002 | 0.002 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".