Table 2.

Goodness of fit metrics for models fit to explain the normalized directional response (Rn)

Formula	R²	Root mean squared error	Sigma	AIC
Rn∼(1\|cell)	0	0.36	0.36	756.23
Rn∼s(log2(speed))	0.52	0.25	0.25	135.58
Rn∼s(log2(speed))+(1\|cell)	0.52	0.25	0.25	137.26

Three GAM models were fit, with potential explanatory variables including log₂ of stimulus speed (speed) and cell identity (cell; as a random effect). Sigma column denotes the residual standard deviation. The best-fitting model, determined by lowest AIC score, is in bold.