Table 1.

Hierarchical regressions comparing models with polynomials of the 1^st to 4^th degree fitted to context concreteness as a function of log geographic distance from the city (Study 1) and log temporal distance from the event in the past (Study 2.1). R² is the amount of the model’s explained variance, ∆R² is the difference in explained variance from the model with a lower order polynomial, and p is the p-value of the comparison of successive models. The cubic polynomial provided the best fit.

	Geographic distance (Study 1)			Temporal distance (Study 2.1)
Polynomial degree	R2	∆R2	p	R2	∆R2	p
Linear	0.775	–	–	0.745	–	–
Quadratic	0.776	0.001	> 0.5	0.749	0.004	0.47
Cubic	0.883	0.107	< 0.001	0.814	0.065	< 0.001
Quartic	0.885	0.002	> 0.5	0.819	0.005	0.40