BeyondPlanck IV. On end-to-end simulations in CMB analysis -- Bayesian versus frequentist statistics

Understand

End-to-end simulations play a key role in the analysis of any high-sensitivity CMB experiment, providing high-fidelity systematic error propagation capabilities unmatched by any other means.

• In this paper, we address an important issue regarding such simulations, namely how to define the inputs in terms of sky model and instrument parameters.
• These may either be taken as a constrained realization derived from the data, or as a random realization independent from the data.
• We refer to these as Bayesian and frequentist simulations, respectively.