no code implementations • 21 Feb 2022 • Seira Hidano, Takao Murakami
Technically, our DPRR uses Warner's RR (Randomized Response) and strategic edge sampling, where each user's sampling probability is automatically tuned using the Laplacian mechanism to preserve the degree information under edge LDP.
no code implementations • 30 Nov 2020 • Seira Hidano, Takao Murakami, Yusuke Kawamoto
Transfer learning has been widely studied and gained increasing popularity to improve the accuracy of machine learning models by transferring some knowledge acquired in different training.
no code implementations • 19 Oct 2020 • Natasha Fernandes, Yusuke Kawamoto, Takao Murakami
Then we show that our mechanisms enable friend matching with high utility and rigorous privacy guarantees based on extended DP.
1 code implementation • 11 Nov 2019 • Takao Murakami, Koki Hamada, Yusuke Kawamoto, Takuma Hatano
We model various statistical features of the original traces by a transition-count tensor and a visit-count tensor.
no code implementations • 13 Jul 2019 • Yusuke Kawamoto, Takao Murakami
We introduce a general model for the local obfuscation of probability distributions by probabilistic perturbation, e. g., by adding differentially private noise, and investigate its theoretical properties.
no code implementations • 3 Dec 2018 • Yusuke Kawamoto, Takao Murakami
To improve the tradeoff between distribution privacy and utility, we introduce a local obfuscation mechanism, called a tupling mechanism, that adds random dummy data to the output.
Cryptography and Security Databases Information Theory Information Theory
no code implementations • 23 Jul 2018 • Yusuke Kawamoto, Takao Murakami
Obfuscation techniques in location-based services (LBSs) have been shown useful to hide the concrete locations of service users, whereas they do not necessarily provide the anonymity.
Cryptography and Security Databases Information Theory Information Theory
no code implementations • 5 Apr 2018 • Takao Murakami, Tetsushi Ohki, Yosuke Kaga, Masakazu Fujio, Kenta Takahashi
Furthermore, existing biometric indexing schemes cannot be used in conjunction with template protection schemes to speed up biometric identification, since a biometric index leaks some information about the original feature.