## 4 Results  
The participants' fixations were first analyzed by checking the attention maps generated by the eye-tracking software (Figure 2). Attention maps in the form of heatmaps are a common way to present a visualization of the density of viewers' eye-tracking data. Different color hues represent different amounts of participants' fixations. Longer fixations recorded on the stimulus are presented by a red color, followed by yellow and green colors. By comparing the regions of the webpage marked in red (Figure 2), a higher prevalence of the red color can be noticed in the ads containing an illustration than on the ads with no illustration, indicating a longer average fixation duration on the illustrated ads.  
The eye-tracking data were then statistically analyzed with IBM SPSS 23. A two-factor repeated measures analysis of variance (ANOVA) was carried out to examine whether ad topic (alcohol vs. smoking) and ad content (text only vs. text with an illustration) significantly influenced the participants' eye-tracking measures. The results showed that ad topic had no influence on any of the measures of visual attention (for both attention attraction and attention maintenance), and this applies to all the examined areas of interest. Ad content had no statistically significant effect on the attention attraction variables (TFF, FB), \(p>0.05\). However, ad content significantly influenced attention maintenance variables. The ads with an illustration had a longer TFD (M = 2.19, SD = 0.18) than the ads with no illustration ((M = 1.78, SD = 1.18), F(1.57) = 4.69, \(p<0.0\)). Furthermore, the illustrated ads had a significantly higher FC (M = 10.36, SD = 0.78) than the ads with no illustration ((M = 8.53, SD = 0.84), F(1.57) = 5.92, \(p<0.05\)), and TVD was also longer for the illustrated digital ads (M = 2.76, SD = 0.23) compared to the ads with no illustration ((M = 2.13, SD = 0.22), F(1.57) = 6.59, \(p<0.05\)). Figure 3 shows the mean values for each measure.  
Figure 1: An example of a stimulus containing one of the digital ads displayed on the webpage used in the experiment (ad topic: smoking, ad content: text with illustration).  
Figure 3: Mean values for eye-tracking data on the digital ads: (**a**) time to first fixation; (**b**) fixations before; (**c**) total fixation duration; (**d**) fixation count; (**e**) total visit duration.  
Figure 2: Heatmaps showing the duration of fixations by all participants (note: only the left area of the webpage is shown to optimize data presentation).  
By analyzing the eye-tracking data recorded only in the area of the illustration (Table 1), we found no significant influence of the illustration's visual representation (man in the bottle vs. man in the ashtray) on any of the variables (all \(p\)s > 0.05).  
[PERSON]'s tests were used to examine the influence of ad topic and ad content on the general noticeability. Figure 4 shows the distribution of participants depending on whether they noticed the ad. The only statistically significant difference was found between the ads containing an illustration and those without, indicating that more participants noticed the ads with text and an illustration (96.6%) than the ads with text only (89.7%); \(p<0.05\).