“…As a result, there are many approaches developed to achieve differential privacy, for instance, Laplacian mechanism [8], exponential mechanism [11], randomized response [4], etc. Among which, randomized response has been widely adopted into a great number of algorithms satisfying differential privacy, such as RAPPOR [4], k-RR [20], O-RR [21], Harmony-mean [23], SHist [31], PrivKVM [17], KVUE [32] and PCKV [18], by virtue of its own merits including simplicity and understandability. As known, randomized response as a means for collecting statistical information in social science was first presented by Warner in 1965 [19], and is proved to perform well in the estimate of statistics.…”