Unique in the shopping mall: On the reidentifiability of credit card metadata

{'id': 'montjoye2015', 'abstract': 'Large-scale data sets of human behavior have the potential to fundamentally transform the way we fight diseases, design cities, or perform research. Metadata, however, contain sensitive information. Understanding the privacy of these data sets is key to their broad use and, ultimately, their impact. We study 3 months of credit card records for 1.1 million people…