get_combined_significance_maps#

gammapy.estimators.utils.get_combined_significance_maps(estimator, datasets)[source]#

Compute excess and significance for a set of datasets.

The significance computation assumes that the model contains one degree of freedom per valid energy bin in each dataset. This method implemented here is valid under the assumption that the TS in each independent bin follows a Chi2 distribution, then the sum of the TS also follows a Chi2 distribution (with the sum of degree of freedom).

See, Zhen (2014): https://www.sciencedirect.com/science/article/abs/pii/S0167947313003204, Lancaster (1961): https://onlinelibrary.wiley.com/doi/10.1111/j.1467-842X.1961.tb00058.x

Parameters:
estimatorExcessMapEstimator or TSMapEstimator

Excess Map Estimator or TS Map Estimator

datasetDatasets

Datasets containing only MapDataset.

Returns:
resultsdict

Dictionary with entries:

  • “significance” : joint significance map.

  • “df” : degree of freedom map (one norm per valid bin).

  • “npred_excess” : summed excess map.

  • “estimator_results” : dictionary containing the flux maps computed for each dataset.

See also

combine_significance_maps

same method but using directly the significance maps from estimators