Serial dependence effect. Figure 3B depicts that
reproduction errors increased with longer prior durations,
indicating a positive assimilation effect. We quantified
this effect using the mean slope b from linear regressions (Eq. 1), resulting in slopes of 0.077 for prior Time and 0.031 for prior Direction tasks, as shown in Figure 3C. Both slopes
were significantly greater than zero (Time:t(23) = 4.370, p < .001,d = 0.892; Direction: t(23) = 2.921, p = .008, d = 0.596), confirming a
sequential effect in both conditions. Interestingly, the sequential effect was significantly larger in the prior Time relative to the Direction condition (t(23) = 2.368, p =.027, d = 0.652). To rule out statistical artifacts \cite{Cicchini2014}, we
also analyzed reproduction errors against durations in future trials, which showed no significance
(ps > .460).
These findings provide clear evidence that, at least in the case of the
time reproduction task, task-relevant response in the preceding trials enhanced the
sequential effect.