> These are the times I get running the other solutions, > 10 runs of 1000 points each. Each run, every solution is > fed the exact same point data. Auuughhh!! Sorry for another self-reply........ :-/ The benchmark script I attached to the earlier post did not, in fact, pass the same point data to each solution per run. (Maybe that'll teach me to make last minute changes without verifying...) The benchmark script at http://tastyspleen.net/~billk/ruby/quiz/157-smallest-circle/benchmark/ now does correctly pass the same coordinate data to each script per run. . . . I had hoped by averaging multiple runs (10) - each run having different point data - that the rankings would have been pretty stable. However, JUSTIN and LIONEL still tend to trade places on different invocations: user system total real FRANK 24.421000 0.297000 24.718000 ( 24.734000) JUSTIN 6.110000 0.000000 6.110000 ( 6.109000) LIONEL 6.078000 0.000000 6.078000 ( 6.094000) DOUG 3.750000 0.000000 3.750000 ( 3.766000) PHILIPP 1.609000 0.000000 1.609000 ( 1.609000) BILL 0.328000 0.000000 0.328000 ( 0.328000) user system total real FRANK 24.656000 0.156000 24.812000 ( 24.828000) LIONEL 6.047000 0.000000 6.047000 ( 6.047000) JUSTIN 4.375000 0.000000 4.375000 ( 4.375000) DOUG 3.281000 0.016000 3.297000 ( 3.297000) PHILIPP 1.500000 0.000000 1.500000 ( 1.500000) BILL 0.297000 0.000000 0.297000 ( 0.297000) user system total real FRANK 24.594000 0.172000 24.766000 ( 24.781000) LIONEL 6.109000 0.000000 6.109000 ( 6.109000) JUSTIN 5.922000 0.000000 5.922000 ( 5.922000) DOUG 4.031000 0.016000 4.047000 ( 4.047000) PHILIPP 1.344000 0.000000 1.344000 ( 1.344000) BILL 0.281000 0.000000 0.281000 ( 0.282000) user system total real FRANK 24.203000 0.391000 24.594000 ( 24.672000) LIONEL 6.109000 0.000000 6.109000 ( 6.125000) JUSTIN 5.500000 0.000000 5.500000 ( 5.500000) DOUG 4.188000 0.016000 4.204000 ( 4.219000) PHILIPP 1.500000 0.000000 1.500000 ( 1.500000) BILL 0.344000 0.000000 0.344000 ( 0.344000) user system total real FRANK 24.546000 0.219000 24.765000 ( 24.765000) JUSTIN 6.047000 0.015000 6.062000 ( 6.062000) LIONEL 5.828000 0.000000 5.828000 ( 5.828000) DOUG 3.641000 0.000000 3.641000 ( 3.641000) PHILIPP 1.688000 0.000000 1.688000 ( 1.688000) BILL 0.296000 0.000000 0.296000 ( 0.296000) (I have verified the rankings are stable if I hardwire the random seed, though.) Regards, Bill