Non-Gaussian error bars in galaxy surveys -- II

Understand

(Abridged) Estimating the uncertainty on the matter power spectrum internally (i.e.

• directly from the data) is made challenging by the simple fact that galaxy surveys offer at most a few independent samples.
• In addition, surveys have non-trivial geometries, which make the interpretation of the observations even trickier, but the uncertainty can nevertheless be worked out within the Gaussian approximation.
• With the recent realization that Gaussian treatments of the power spectrum lead to biased error bars about the dilation of the baryonic acoustic oscillation scale, efforts are being directed towards developing non-Gaussian analyses, mainly from N-body simulations so far.