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The LA Times just posted its review of "Heart of a Soldier", the San Francisco Opera's newly commissioned opera about the life of Rick Rescorla which premiered last night. You may not remember his name, but Rescorla was the head... Continue reading
Posted Sep 11, 2011 at Locus Medius
It's not really accurate to say that they "fit" polling data to a bell curve. The bell curve is used only to determine the sampling error — the only error information actually reported in these polls. In fact, that's not even totally accurate. There is a formula for determining the sampling error that was derived based on sample error being distributed along a bell curve. The sampling error is the error caused by polling a subset of voters. So the sampling error they report is really the answer to the question "how far off could the poll be merely because we might have accidentally not polled a representative population?" (Actually, the question needs to add the additional information that we want to know how far off we could be such that 95% of the time we'd be within that range.) The sampling error is determined only by plugging the number of voters polled and the estimated total number of voters into a standard formula.
85% is sort of a meaningless number without knowing more information. For all we know from that table, it takes 90% of the performance of a 24" barrel to reliably drop a man at range. If that was the case, then the complaints about the M4 would be justified. Considering there are complaints about the performance of even the 20"-barrelled M16, then anything that performed even a little worse would probably be noticeable. The other thing I would want to know is what type of rifling they used. Supposedly, polygonal rifling allows for higher muzzle velocities compared to traditional rifling. If so, then the M4's problem could be the short barrel combined with the old-style rifling. When the XM8 was being discussed, it was claimed that the 12.5" barrel would not be a problem on the personal defense version because it would perform pretty close to the 14.5" barrel on the M4, due to the rifling design.
Commented May 23, 2006 on 5.56mm barrel length at Airborne Combat Engineer