The magnitude of neural responses in sensory cortex depends on the intensity of a stimulus and its probability of being observed within the environment. How these two variables combine to influence the overall response of cortical populations remains unknown. The published datasets show that, in primary visual cortex, the vector magnitude of the population response is described by a separable power-law that factors the intensity of a stimulus and its probability. These data are described in Tring et al, "On the contrast response function of adapted neural populations," published in J.Neurophysiol, 2024.