OK. When I you were helping me with the jones probability calculations, I had already written a program to test random predictions like that against the real database. I just ran it again.

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reading file...
 3  H:/Geo/earthquakes/Catalogs/ANSS catalog/6.5 and up 1980-20131006.txt
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  Start Date: 2444239.50000000
    End Date: 2456571.50000000
   Time Span:  12333 days
total quakes:  1261
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computing Jones probability...
loop time:   0.047
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      Window Size:  3 days
      No. Windows:  4111
      Window Hits:  990
Jones Probability:  .24081731938701
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loop time:   8.969
Results of run  1
Number of random samples: 1000000
Number of hits against real data: 306840
resulting random probability: .30684
loop time:   8.953
Results of run  2
Number of random samples: 1000000
Number of hits against real data: 305736
resulting random probability: .305736
loop time:   8.953
Results of run  3
Number of random samples: 1000000
Number of hits against real data: 307256
resulting random probability: .307256
loop time:   8.953
Results of run  4
Number of random samples: 1000000
Number of hits against real data: 307379
resulting random probability: .307379
loop time:   8.953
Results of run  5
Number of random samples: 1000000
Number of hits against real data: 306306
resulting random probability: .306306
loop time:   9.172
Results of run  6
Number of random samples: 1000000
Number of hits against real data: 306435
resulting random probability: .306435
loop time:   8.969
Results of run  7
Number of random samples: 1000000
Number of hits against real data: 307479
resulting random probability: .307479
loop time:   8.969
Results of run  8
Number of random samples: 1000000
Number of hits against real data: 307087
resulting random probability: .307087
loop time:   8.953
Results of run  9
Number of random samples: 1000000
Number of hits against real data: 306563
resulting random probability: .306563
loop time:   8.954
Results of run  10
Number of random samples: 1000000
Number of hits against real data: 307259
resulting random probability: .307259
Average probability of 10 runs of 1000000 random predictions each: .306834
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done.
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