cstat¶
-
gammapy.stats.
cstat
(n_on, mu_on, n_on_min=1e-25)[source]¶ C statistic, for Poisson data.
The C statistic is defined as
\[C = 2 \left[ \mu_{on} - n_{on} + n_{on} (\log(n_{on}) - log(\mu_{on}) \right]\]and \(C = 0\) where \(\mu_{on} <= 0\).
n_on_min
handles the case wheren_on
is 0 or less and the log cannot be taken. For more information see Fit statistics- Parameters
- n_onarray_like
Observed counts
- mu_onarray_like
Expected counts
- n_on_minarray_like
n_on
=n_on_min
wheren_on
<=n_on_min.
- Returns
- statndarray
Statistic per bin
References