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arXiv · 1704.08547

Privacy Assessment of De-identified Opal Data: A report for Transport for NSW

Chris Culnane·Benjamin I. P. Rubinstein·Vanessa Teague
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Abstract

We consider the privacy implications of public release of a de-identified dataset of Opal card transactions. The data was recently published at https://opendata.transport.nsw.gov.au/dataset/opal-tap-on-and-tap-off. It consists of tap-on and tap-off counts for NSW's four modes of public transport, collected over two separate week-long periods. The data has been further treated to improve privacy by removing small counts, aggregating some stops and routes, and perturbing the counts. This is a summary of our findings.

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Chris Culnane, Benjamin I. P. Rubinstein, Vanessa Teague. 2017-04-27. Privacy Assessment of De-identified Opal Data: A report for Transport for NSW. https://arxiv.org/abs/1704.08547

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