Posted by Lowell on November 29, 2001 at 22:57:50:
By the way, Don and Petra, I wonder if you recall that Don had a prediction outstanding for that Alder Springs event that suddenly appeared this afternoon on the maps and listings. On Nov. 14 Don had forecast an event for Alder Springs (# 10956) NCSN is reporting the following parameters for this event: O: 26NOV2001 18:20:20 39.7N 122.8W ML=3.2 NCSN NW of Alder Springs, CA Don's forecast had been for: P: 16-20NOV 40 km 39.9N 122.6W Ml 2.4-3.7 Alder Springs, CA The forecast correctly identified the location (the event is 27 km from the forecast epicenter) and magnitude range - the earthquake magnitude of Ml 3.2 was in the middle of the expected range. To spoil, the forecast, however, the event occurred 6 days later than the end of the time window. Probability: During the past year there have been 11 11-day intervals in which an event occurred which would have matched Don's forecast, 3 of which contained an event of Ml>=3. In the same period there have been 33 such 11-day periods, so the probability of random success starting with the first day of Don's forecast and including the Alder Springs event is about 11/33 = 0.33 or odds of 1 in 3 for a successful random forecast. Had Don chosen to limit his magnitude to 3.0+ his odds of random success in an 11-day period would have been about 1 in 11. Don's prediction had been: Alder Springs, California Earthquake Forecast Posted by Don In Hollister on November 14, 2001 at 16:49:28: Magnitude: 2.4-3.7Md From: 11/16/2001PST - To: 11/20/2001PST Location: Alder Springs, California Lat: 39.9N - Long: 122.6W - Range: 40Km Hi All. Looking for a 2.4 to 3.7Md quake at 39.9N/122.6W. This is about 30Km NNE of Alder Springs. Should occur on 11/18/2001. The window will open on 11/16/2001 and will close on 11/20/2001. The radius on this will be 40Km. Take Care...Don in creepy town
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