Table 5.

PD Production fixed effects.

Parameter	Estimate	Std. Error	t-value
Intercept	53.669	12.045	4.46**
X position	426.278	128.872	3.31**
Real objects	0.358	4.479	0.08
X position × Real objects	−442.617	127.100	−3.48**
X position2	−4.004	29.842	−0.13
X position2 × Real objects	26.541	30.488	0.87

^**p < 0.01.