Cathryn, I have been quite surprised that Don's prediction has not shown up on the charts
as an actual event, as were you. In fact, I was so surprised, that I went checking and
guess what I found in the CNSS catalog that Roger is using to evaluate the predictions.

That's right, Don's forecast event did happen after all (probably)

The problem is that because the earthquake was small in an area where few seismometers
are located, no magnitude has (or can?) be assigned to it - that is CNSS has no
magnitude card because at the moment NCSN has not yet assigned a magnitude
to this event.

The event is listed as:

$loc 20020319162702.6500 39.48917-121.53450 11.8500H NC

For those of you who can't read this, it is an event that occurred on March 19, 2002
at 39.48N 121.53W at 16:27 UT, but it was not possible to determine the magnitude
due to poor seismograph distribution in the area. Checking, I found that the smallest
magitude given an event in the 35 km radius Don had set in the past past year
was slightly more than Ml 1.4. Apparently anything at or near that size is not
given a magnitude by NCSN. There have been 18 of 73 5-day periods in the last year
during which an event of any size has been recorded in the catalog. So the chance
of a random guess on an event of any size (even the ones for which a magnitude was
not determined) in this region in a 5-day period is about 18/73 = 0.25 or odds
of 1 in 4. Don had expected an event of Ml 1.7-3.0 between March 18 and 22 at
39.4N 121.2W. This event falls within Don's radius and is in the middle of the
time window, but because it was not assigned a magnitude, it slipped through
Roger's mesh.
Anyway, win or lose, Don can take some pride in picking this unusual event
within the time frame established.