CR–M relation coefficients as a function of simulation parameters, for large volumes emulated at z = 0.21. The x-axis varies the A_SN1 feedback parameter, while the line colour denotes a change in A_SN2. The top and bottom panels respectively show the variations of the slope α_CR − M and of the intrinsic scatter σ_CR − M. The error bars show the interval covering 68% of the measured point around the median. The lines have been slightly shifted horizontally to improve readability.