Methodology for comparing analytical (red) and empirical (blue) noise estimates. Empirical errors are obtained from on-sky data cubes by projecting the ERR extension values onto the template, as well as by calculating the spatial standard deviation of the CCF. These empirical values are then compared to the analytical errors derived from FastCurves, both with and without consideration of the systematic noise component (estimated with MIRISim), in addition to the fundamental noise sources.