.02

> Regarding the rectangle option, some error may be introduced by:

> - The "rectangle" is really a trapezoid curved to match the surface of the earth. If you chose a southern corner the range will likely be longer than if you choose a northern corner. This creates a deviation in the probability calculation.

Picky, picky picky!

You're correct though. I don't think it matters much since we're talking near-misses here anyway.

> You may want to dis-allow this option as an input.

I don't want to tell people how to predict any more than necessary.

> Do you use an oblate earth to calculate the deviation from a spherical earth (lat, long) location (before calculating the distance between candidate quake and predicted quake)?

To tell the truth, I don't know. I swiped the formula from a government Java distance finder.

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> You said: "If the quake does not meet the predicted range, the range is extended in 10%
increments until the quake falls inside the extended range. This range is then
used in the probability calculation."

> + I read this as you use the 10 % extended range distance and not the candidate quake distance. Is that correct?

Yes. I use a range distance just because they didn't predict an actual distance to begin with.

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> You said: "In the case of magnitudes, largest is considered the "best fit".

> + Just what if some predictor thought that he had a good way to determine magnitude and specified a lower magnitude range (e.g. 3-4). Then by choosing the largest to hit in the interval you have broken this predictor's line of thinking in doing the evaluation. The predictor would score himself a miss or WIA (for missing the higher magnitude quake) when your program would give him a different score (by using the largest instead on one closer in magnitude...).

Then he needs to mention that fact so I can adjust the program for him.

The idea was that bigger is better (more important) which is usually true.

> This area may have to be re-visited at a future time.

Anything is possible.

Roger