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Old August 12th 17, 10:08 AM posted to sci.astro
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Default 1) the negative paraxes...

Il giorno sabato 7 gennaio 2017 11:08:29 UTC+1, ha scritto:
Il giorno martedì 27 dicembre 2016 10:38:25 UTC+1, ha scritto:
Il giorno domenica 18 dicembre 2016 12:16:55 UTC+1, ha scritto:
Il giorno mercoledì 14 dicembre 2016 14:43:54 UTC+1, Mike Dworetsky ha scritto:
wrote:
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. Would you be happy with that? I wouldn't.