##

weight

change weighting used in computing statistic
Change the weighting function used in the calculation of chi-squared.

Syntax: |
weight |
`[standard | gehrels | churazov | model]` |

`standard` weighting uses or the statistical error given in
the input spectrum. `gehrels` weighting uses
,
a better approximation when N is small (Gehrels, N. 1986, ApJ 303, 336).
`churazov` weighting uses the suggestion of Churazov et al.
(1996, ApJ 471, 673) to estimate the weight for a given channel by averaging
the counts in surrounding channels. `model` weighting uses the value of
the model, not the data, to estimate the weight.