“…In this method, the descriptions of error statistics and error distribution are numerical data, which cannot be parameterized according to the circuit design. References [15][16][17] proposed a series of error characteristic metrics, including error rate, error distance, mean error distance, normalized mean error distance, relative error distance, mean relative error distance, etc. These metrics are widely used to analyze and compare existing ACCs or evaluate newly proposed ACCs, including various approximate adders [17,18] , approximate multipliers [19] , and approximate dividers [20] .…”