optimistic
Posted by John Vidale on October 08, 2008 at 09:35:06:

I do check posts here from time to time, and coincidently, yesterday I was looking into commenting on this "news". This is the essence of my opinion.

1. It is called News, while it really from a less-than-objective point of view, and probably should have been a letter.

2. It contains the claim "It has been found that such an analysis enables the identification of the time before the mainshock usually within a few days". That is not my understanding of the community consensus.

3. The article (http://arxiv.org/pdf/0711.3766v3) gave location information, so far as I can tell from a cursory reading, of

"Their subsequent seismicities are currently studied along the lines explained above considering the evolving seismicity in the following areas: Concerning the former SES activity at PAT the areas depicted in Fig.13, while for the one at PIR on 14 January, 2008, the subsequent seismicity is studied in the area B of Fig.9 as well as in the larger area N36.0-38.6 E20.0-22.5 and in the one surrounding the epicenter[69] (36oN 23oE)."

(area B is previously defined as N37.6-38.6 E 20.0-22.2)

So the 2/14 mainshock, located at 36.626°N, 21.792°E, fell in the largest area, not in the smaller area, and I didn't see a radius specified for the third possibility, "surrounding the epicenter", but it was 100+ km south of the cited location (36N,23E). So the prediction really only hit one out of three possibilities offered.

4. No time window was specified.

5. The title of the "News" is that 2 quakes were predicted, but I saw no evidence of 2 predictions, and as noted above, even one is a stretch.

6. Finally, were one to assess how unlikely such a "prediction" were to be fulfilled at random, the odds are greatly increased by the quite recent earthquake activity in the same region, so it is not impressive as one might guess not knowing about the recent activity.

The bottom line is that one must consider the entire set of predictions, and my impression is that cumulatively, last I heard, the VAN group was doing WORSE than random guessing. A news article that takes one result out of a suite of predictions without considering the whole is optimistic at best.


Follow Ups:
     ● Re: optimistic - Mike Williams in Arroyo Grande  21:19:59 - 10/12/2008  (74410)  (1)
        ● Re: optimistic - Cathryn  04:13:36 - 10/20/2008  (74415)  (0)