It took a little work but I finally figured out Bob's clever format for the summary information. Guess I passed the IQ test...(wink).
Anyway, using the motor totals for all seven years from his web site and running them through my curve fit analysis to get a broad view of RMR's 'style' of rocketry I get the following. What I call a "group" can be viewed as a group of flyers but is more likely a "style" or "attitude" of rocketry. I excluded Micro-Maxx because it's really its own thing, and besides, including it would have screwed up the math. The curve fit does in fact reveal that it would show up as a separate group anyway.
The way I do the math, 1/4A is size class zero, 1/2A is class 1, M+ is size class 14.
The low power group is characterized by a mean motor class size of
3.54 (halfway between B and C) and a standard deviation of 1.76 classes. The high power group is characterized by a mean of 8.21 (a bit over G) and a standard deviation of 1.37.Running a trimodal analysis refines these numbers only slightly. The third group shows up as a small excess of 'C' motors(1 percent of launches) forming a group with mean of 3.97 and a std. dev. of 0.12 size classes(effectively a small spike at C). The low power group changes slightly to a mean of 3.43 and a std. dev. of 1.81 (75% of launches)while the high power group becomes a mean of 8.11 and a std. dev. of 1.55 (24% of launches). Overall this is a slightly better fit, but both solutions are only an "ok" fit by comparison to what I usually get. (On data from some local launches I've obtained trimodal fits that were SCARY good!) In either solution the low power group is obviously truncated at 1/4A indicating that it's not surprising that they would fly 1/16A Micro-Maxx motors, although not in the numbers reported. Like I said, Micro-Maxx is its own thing.
For comparison, data from OregonRocketry launches at our eastern Oregon site breaks down into the following three modes: Low power, mean 4.08 std. dev. 1.22, 43% of launches mid-power, mean 7.44 std. dev. 0.57, 11% of launches (F and G exclusively) high power, mean 9.81 std. dev. 1.38, 46% of launches
What is interesting about this kind of analysis is that the observed motor usage indicates that rocketry has not yet evolved into one continuum of activity. The low power group essentially never flies anything over a G motor. The high power group essentially never flies anything smaller than a C or D motor. The "notch" at E is simply an artifact of the way the low and high power groups overlap.
Another interesting point is that the bell curve model applies to MOTOR CLASSES, not newton-seconds. The difference between the means of the low and high power groups is 4.7 letter classes, translating into a factor of 25.6 times increase in newton-seconds. But that in turn translates into a linear scaling factor of about 2.95. IOW, the difference between RMR's low power and high power groups is 3x upscale.
Maybe later I'll do some more number crunching on the data and look at some other aspects of it. Meanwhile, posting more detailed info like graphs would depend on exporting the worksheet from Mathcad +6.0 (involving complete reformatting) to an RTF file and uploading to somebody's web site.
+McG+