The Murchison Widefield Array 21 cm Power Spectrum Analysis Methodology
  We present the 21 cm power spectrum analysis approach of the Murchison
Widefield Array Epoch of Reionization project. In this paper, we compare the
outputs of multiple pipelines for the purpose of validating statistical limits
cosmological hydrogen at redshifts between 6 and 12. Multiple, independent,
data calibration and reduction pipelines are used to make power spectrum limits
on a fiducial night of data. Comparing the outputs of imaging and power
spectrum stages highlights differences in calibration, foreground subtraction
and power spectrum calculation. The power spectra found using these different
methods span a space defined by the various tradeoffs between speed, accuracy,
and systematic control. Lessons learned from comparing the pipelines range from
the algorithmic to the prosaically mundane; all demonstrate the many pitfalls
of neglecting reproducibility. We briefly discuss the way these different
methods attempt to handle the question of evaluating a significant detection in
the presence of foregrounds.
