Table 2. Models of contrast sensitivity across eccentricity and polar angle.

The bolded entry indicates the best-fitting model.

Model label	Description	Max number of parameters
Ecc + HVA + VMA	CSFs vary across eccentricity and polar angle	24
Ecc +HVA - VMA	CSFs do not vary along the VM	16
Ecc - HVA + VMA	CSFs do not vary along the HM	16
-Ecc + HVA + VMA	CSFs do not vary across eccentricity	12
Ecc - HVA - VMA	CSFs do not vary along the VM and HM	8
-Ecc - HVA - VMA	CSFs are identical at all visual field locations	4

CSF: contrast sensitivity function; VM: vertical meridian; HM: horizontal meridian; HVA: horizontal-vertical anisotropy; VMA: vertical meridian asymmetry.