Just in case we were wondering, the V1 bolocat is completely inconsistent with a lognormal distribution, but is perfectly consistent (or... at least reasonably consistent...) with a power law distribution.
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These plots show power-law fits (red) and lognormal fits (blue) to the data (black). It's pretty obvious that the lognormal is a bad fit, but in case you're unconvinced, the ks test for the "source flux" has a probability 1.6e-7, and it is the highest likelihood by 17 orders of magnitude out of the 4 flux types. By contrast, the simulations are on average (though not uniformly) more consistent with lognormal than powerlaw distributions:
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Even in those examples where the KS test is slightly more favorable for the powerlaw distribution, the lognormal is a pretty good fit, and the failure points for the two distributions are in about the same place. The smoothness of the lognormal distribution is required to reproduce the observed distribution.
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Note that the first 4 plots are for the whole BGPS survey. What about an individual field? For obvious reasons, I choose l30 again.
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This gets to be a little more interesting - apparently the "source flux" has a tendency to pick up the power-law distributed background structure, since it is consistent with a lognormal (but note that it is also consistent with a powerlaw! The ks test doesn't really say definitively which is better). Although the fits look bad at high flux, note that this is a log-log plot and therefore the difference in probability is rather small. What does this all indicate? It's not entirely clear whether individual fields are genuinely more lognormally-distributed or whether the number statistics are just worse. However, even the source flux is consistent with a power-law, while many realizations of the simulations are not. Therefore, we should perform the next logical test - add point sources drawn from a power-law distribution (and a log-normal distribution?) and see what bolocat retrieves. We can at least say now that the point source contribution cannot be ignored, since there is no power-law distribution that can reproduce the observed bolocat flux distribution.