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Old December 14th 16, 08:11 AM posted to sci.astro
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Default 1) the negative paraxes...

Il giorno mercoledì 14 dicembre 2016 08:44:15 UTC+1, Poutnik ha scritto:
Dne 13/12/2016 v 09:44 Martin Brown napsal(a):
On 12/12/2016 06:42, Poutnik wrote:

For exactly the reason I stated in the part of my reply that you
snipped: Negative values are unphysical, but form the part of the
statistical distribution of values that happen to lie below zero when
the mean is close to zero.

Positive and negative noise values are equally unphysical.

But you only know for certain that the negative values are unphysical
the positive ones could be real to within some measurement error. Later
more refined experiments may be able to narrow down the error bars.

Later experiment can. But I speak in context of this one.
These small values are not statistically justified,
as there is high probability it is just a noice.

Imagine that someone plotted a graph of, say, a spectrum (with low S/N),
and wherever the plotted flux was below zero, they simply truncated it.