Sadly, Mr. Gel-pack, you're missing the point. Having studies statistics you are trying to deal with this issue as if it were rational. It is not, it is political. SATSO obviously does not know statistics, but seems to have an excellent grasp of politics. Nobody at TSA cares a whit about β (type 2 error, false positive) thus they merrily run endless tests and physical inspections as if they would reduce the incidence of α (type 1 error, false negative). The TSA cares only, I shout ONLY about type 1 error.

Because there are political risks the obvious and clear high correlations between actual presence of destructive capacity and factors the TSA will not examine make any form of statistical analysis useless. The very fact that high risk arenas such as freight were not even examined until very recently makes the point.

I wish it were different but we must accept that the government would p[refer to waste time for millions of citizens and tourists, spend scarce resources and employ tens of thousands of marginally qualified people rather than allow root cause analysis and decent probabilistic evaluations to play a part.

MTBF is fine for aircraft doors, and good statistical analysis explains why aircraft failures are so very rare that we hear about every one that happens anywhere in the world. It is not fine if the statistical analysis itself demonstrates the failure of the political process, as it does.

if I made all this any less dry, it would need to be in OMNI.