Temporal evolution of the central fixation bias 7 All figures were created with the ggplot2 package (Wickham, 2009) of the R-Language of Statistical Computing. Influence of the initial fixation on the second fixation . The pre-trial fixation time influ- enced the DTC on early fixations. To further investigate this influence, we plot the DTC of the second fixation as a function of overall saccade latency from image onset. We com- puted linear mixed models (Bates, M¨ achler, Bolker, & Walker, 2015) with initial saccade latency and pre-trial fixation time as fixed effects, the DTC of the second fixation as the dependent variable and an intercept for subjects and images as random factors. To com- pute the models, we transformed DTC with the boxcox function of the R package MASS (Venables & Ripley, 2002) to follow a normal distribution. We obtained significance levels with the lmerTest package (Kuznetsova, Brockhoff, & Christensen, 2013). Contrasts were defined as sum contrasts. This means that each pre-trial fixation time is compared to the overall mean of distance to center. To be able to compare the different factor levels to the overall mean, the highest pre-trial fixation time in each experiment was left out. In all experiments we excluded saccades with a latency smaller than or equal to 80 ms as anticipatory. Density Maps of eye positions over time . To visualize the temporal evolution of eye positions in our experiments, we computed movies of 2D density maps for the different pre- trial fixation times and each eye position of the time-series recorded for each experiment. Based on a kernel density estimation via diffusion (Botev, Grotowski, & Kroese, 2010), we estimated density maps for the first two seconds (after removal of the fixation cross) in each experiment. These movies are available as supplementary material.