We prove a general lower bound on the average-case complexity of Shellsort:
the average number of data-movements (and comparisons) made by a p-pass
Shellsort for any incremental sequence is \Omega (pn^{1 + 1/p) for all p≤logn. Using similar arguments, we analyze the average-case complexity
of several other sorting algorithms.Comment: 11 pages. Submitted to ICALP'9