An Efficient Algorithm for the Approximate Median Selection Problem
نویسندگان
چکیده
We present an efficient algorithm for the approximate median selection problem. The algorithm works in-place; it is fast and easy to implement. For a large array it returns, with high probability, a very close estimate of the true median. The running time is linear in the length n of the input. The algorithm performs fewer than 4 3 n comparisons and 1 3 n exchanges on the average. We present analytical results of the performance of the algorithm, as well as experimental illustrations of its precision.
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تاریخ انتشار 2000